Merge branch 'master' into DRTVWR-515-maint

# Conflicts:
#	indra/newview/llpanelprimmediacontrols.cpp

23 files changed, 1365 insertions, 1457 deletions

diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index a18492c554..927b49107a 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -812,17 +812,6 @@
       <key>Value</key>
       <integer>0</integer>
     </map>
-    <key>FramePerSecondLimit</key>
-    <map>
-      <key>Comment</key>
-      <string>Controls upper limit of frames per second</string>
-      <key>Persist</key>
-      <integer>1</integer>
-      <key>Type</key>
-      <string>U32</string>
-      <key>Value</key>
-      <integer>120</integer>
-    </map>
     <key>BackgroundYieldTime</key>
     <map>
       <key>Comment</key>
@@ -14420,7 +14409,7 @@
     <key>VoiceCallsFriendsOnly</key>
     <map>
       <key>Comment</key>
-      <string>Only accept voice calls from residents on your friends list</string>
+      <string>(Deprecated) Only accept voice calls from residents on your friends list</string>
       <key>Persist</key>
       <integer>1</integer>
       <key>Type</key>
diff --git a/indra/newview/app_settings/settings_per_account.xml b/indra/newview/app_settings/settings_per_account.xml
index 8f4ca6c633..537744b44c 100644
--- a/indra/newview/app_settings/settings_per_account.xml
+++ b/indra/newview/app_settings/settings_per_account.xml
@@ -220,6 +220,17 @@
         <key>Value</key>
             <integer>1</integer>
         </map>
+    <key>VoiceCallsFriendsOnly</key>
+    <map>
+        <key>Comment</key>
+        <string>Only accept voice calls and receive IMs from residents on your friends list</string>
+        <key>Persist</key>
+        <integer>1</integer>
+        <key>Type</key>
+        <string>Boolean</string>
+        <key>Value</key>
+        <integer>0</integer>
+    </map>
     <key>VoiceEffectDefault</key>
     <map>
         <key>Comment</key>
diff --git a/indra/newview/app_settings/shaders/class1/deferred/cloudsV.glsl b/indra/newview/app_settings/shaders/class1/deferred/cloudsV.glsl
index caa4fe1f65..b7036e02cf 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/cloudsV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/cloudsV.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file WLCloudsV.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2005, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -33,26 +33,26 @@ ATTRIBUTE vec2 texcoord0;
 ///////////////////////////////////////////////////////////////////////////////
 
 // Output parameters
-VARYING vec4 vary_CloudColorSun;
-VARYING vec4 vary_CloudColorAmbient;
+VARYING vec4  vary_CloudColorSun;
+VARYING vec4  vary_CloudColorAmbient;
 VARYING float vary_CloudDensity;
 
-VARYING vec2 vary_texcoord0;
-VARYING vec2 vary_texcoord1;
-VARYING vec2 vary_texcoord2;
-VARYING vec2 vary_texcoord3;
+VARYING vec2  vary_texcoord0;
+VARYING vec2  vary_texcoord1;
+VARYING vec2  vary_texcoord2;
+VARYING vec2  vary_texcoord3;
 VARYING float altitude_blend_factor;
 
 // Inputs
 uniform vec3 camPosLocal;
 
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 
@@ -60,7 +60,7 @@ uniform float cloud_shadow;
 uniform float density_multiplier;
 uniform float max_y;
 
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float sun_moon_glow_factor;
 
 uniform vec4 cloud_color;
@@ -70,133 +70,123 @@ uniform float cloud_scale;
 // NOTE: Keep these in sync!
 //       indra\newview\app_settings\shaders\class1\deferred\skyV.glsl
 //       indra\newview\app_settings\shaders\class1\deferred\cloudsV.glsl
+//       indra\newview\app-settings\shaders\class2\windlight\cloudsV.glsl
 //       indra\newview\lllegacyatmospherics.cpp
+//       indra\newview\llsettingsvo.cpp
 void main()
 {
-
-	// World / view / projection
-	gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0);
-
-	// Texture coords
-	vary_texcoord0 = texcoord0;
-	vary_texcoord0.xy -= 0.5;
-	vary_texcoord0.xy /= cloud_scale;
-	vary_texcoord0.xy += 0.5;
-
-	vary_texcoord1 = vary_texcoord0;
-	vary_texcoord1.x += lightnorm.x * 0.0125;
-	vary_texcoord1.y += lightnorm.z * 0.0125;
-
-	vary_texcoord2 = vary_texcoord0 * 16.;
-	vary_texcoord3 = vary_texcoord1 * 16.;
-
-	// Get relative position
-	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
-
-    altitude_blend_factor = clamp((P.y + 512.0) / max_y, 0.0, 1.0);
-
-	// Set altitude
-	if (P.y > 0.)
-	{
-		P *= (max_y / P.y);
-	}
-	else
-	{
-		altitude_blend_factor = 0; // SL-11589 Fix clouds drooping below horizon
-		P *= (-32000. / P.y);
-	}
-
-	// Can normalize then
-	vec3 Pn = normalize(P);
-	float  Plen = length(P);
-
-	// Initialize temp variables
-	vec4 temp1 = vec4(0.);
-	vec4 temp2 = vec4(0.);
-	vec4 blue_weight;
-	vec4 haze_weight;
-	//vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-	vec4 sunlight = sunlight_color;
-	vec4 light_atten;
-
-    float dens_mul = density_multiplier;
-
-	// Sunlight attenuation effect (hue and brightness) due to atmosphere
-	// this is used later for sunlight modulation at various altitudes
-	light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
-
-	// Calculate relative weights
-	temp1 = abs(blue_density) + vec4(abs(haze_density));
-	blue_weight = blue_density / temp1;
-	haze_weight = haze_density / temp1;
-
-	// Compute sunlight from P & lightnorm (for long rays like sky)
-	temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
-	temp2.y = 1. / temp2.y;
-	sunlight *= exp( - light_atten * temp2.y);
-
-	// Distance
-	temp2.z = Plen * dens_mul;
-
-	// Transparency (-> temp1)
-	// ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
-	// compiler gets confused.
-	temp1 = exp(-temp1 * temp2.z);
-
-
-	// Compute haze glow
-	temp2.x = dot(Pn, lightnorm.xyz);
-	temp2.x = 1. - temp2.x;
-		// temp2.x is 0 at the sun and increases away from sun
-	temp2.x = max(temp2.x, .001);	
-		// Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-	temp2.x *= glow.x;
-		// Higher glow.x gives dimmer glow (because next step is 1 / "angle")
-	temp2.x = pow(temp2.x, glow.z);
-		// glow.z should be negative, so we're doing a sort of (1 / "angle") function
-
-    temp2.x *= sun_moon_glow_factor;
-
-	// Add "minimum anti-solar illumination"
-	temp2.x += .25;
-
-	// Increase ambient when there are more clouds
-	vec4 tmpAmbient = ambient_color;
-	tmpAmbient += (1. - tmpAmbient) * cloud_shadow * 0.5; 
-
-	// Dim sunlight by cloud shadow percentage
-	sunlight *= (1. - cloud_shadow);
-
-	// Haze color below cloud
-	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
-				+ (haze_horizon * haze_weight) * (sunlight * temp2.x + tmpAmbient)
-			 );	
-
-	// CLOUDS
-	temp2.y = max(0., lightnorm.y * 2.);
-	temp2.y = 1. / temp2.y;
-	sunlight *= exp( - light_atten * temp2.y);
-
-	// Cloud color out
-	vary_CloudColorSun = (sunlight * temp2.x) * cloud_color;
-	vary_CloudColorAmbient = tmpAmbient * cloud_color;
-	
-	// Attenuate cloud color by atmosphere
-	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
-	vary_CloudColorSun *= temp1;
-	vary_CloudColorAmbient *= temp1;
-	vec4 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - temp1);
-
-	// Make a nice cloud density based on the cloud_shadow value that was passed in.
-	vary_CloudDensity = 2. * (cloud_shadow - 0.25);
-
-
-	// Combine these to minimize register use
-	vary_CloudColorAmbient += oHazeColorBelowCloud;
-
-	// needs this to compile on mac
-	//vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
-
-	// END CLOUDS
+    // World / view / projection
+    gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0);
+
+    // Texture coords
+    // SL-13084 EEP added support for custom cloud textures -- flip them horizontally to match the preview of Clouds > Cloud Scroll
+    vary_texcoord0 = vec2(-texcoord0.x, texcoord0.y);  // See: LLSettingsVOSky::applySpecial
+
+    vary_texcoord0.xy -= 0.5;
+    vary_texcoord0.xy /= cloud_scale;
+    vary_texcoord0.xy += 0.5;
+
+    vary_texcoord1 = vary_texcoord0;
+    vary_texcoord1.x += lightnorm.x * 0.0125;
+    vary_texcoord1.y += lightnorm.z * 0.0125;
+
+    vary_texcoord2 = vary_texcoord0 * 16.;
+    vary_texcoord3 = vary_texcoord1 * 16.;
+
+    // Get relative position
+    vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0);
+
+    altitude_blend_factor = clamp((rel_pos.y + 512.0) / max_y, 0.0, 1.0);
+
+    // Set altitude
+    if (rel_pos.y > 0)
+    {
+        rel_pos *= (max_y / rel_pos.y);
+    }
+    if (rel_pos.y < 0)
+    {
+        altitude_blend_factor = 0;  // SL-11589 Fix clouds drooping below horizon
+        rel_pos *= (-32000. / rel_pos.y);
+    }
+
+    // Can normalize then
+    vec3  rel_pos_norm = normalize(rel_pos);
+    float rel_pos_len  = length(rel_pos);
+
+    // Initialize temp variables
+    vec4 sunlight = sunlight_color;
+    vec4 light_atten;
+
+    // Sunlight attenuation effect (hue and brightness) due to atmosphere
+    // this is used later for sunlight modulation at various altitudes
+    light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
+
+    // Calculate relative weights
+    vec4 combined_haze = abs(blue_density) + vec4(abs(haze_density));
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = haze_density / combined_haze;
+
+    // Compute sunlight from rel_pos & lightnorm (for long rays like sky)
+    float off_axis = 1.0 / max(1e-6, max(0., rel_pos_norm.y) + lightnorm.y);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Distance
+    float density_dist = rel_pos_len * density_multiplier;
+
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati
+    // compiler gets confused.
+    combined_haze = exp(-combined_haze * density_dist);
+
+    // Compute haze glow
+    float haze_glow = 1.0 - dot(rel_pos_norm, lightnorm.xyz);
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);
+    // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
+
+    haze_glow *= sun_moon_glow_factor;
+
+    // Add "minimum anti-solar illumination"
+    // For sun, add to glow.  For moon, remove glow entirely. SL-13768
+    haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (haze_glow + 0.25);
+
+    // Increase ambient when there are more clouds
+    vec4 tmpAmbient = ambient_color;
+    tmpAmbient += (1. - tmpAmbient) * cloud_shadow * 0.5;
+
+    // Dim sunlight by cloud shadow percentage
+    sunlight *= (1. - cloud_shadow);
+
+    // Haze color below cloud
+    vec4 additiveColorBelowCloud =
+        (blue_horizon * blue_weight * (sunlight + tmpAmbient) + (haze_horizon * haze_weight) * (sunlight * haze_glow + tmpAmbient));
+
+    // CLOUDS
+    off_axis = 1.0 / max(1e-6, lightnorm.y * 2.);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Cloud color out
+    vary_CloudColorSun     = (sunlight * haze_glow) * cloud_color;
+    vary_CloudColorAmbient = tmpAmbient * cloud_color;
+
+    // Attenuate cloud color by atmosphere
+    combined_haze = sqrt(combined_haze);  // less atmos opacity (more transparency) below clouds
+    vary_CloudColorSun *= combined_haze;
+    vary_CloudColorAmbient *= combined_haze;
+    vec4 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - combined_haze);
+
+    // Make a nice cloud density based on the cloud_shadow value that was passed in.
+    vary_CloudDensity = 2. * (cloud_shadow - 0.25);
+
+    // Combine these to minimize register use
+    vary_CloudColorAmbient += oHazeColorBelowCloud;
+
+    // needs this to compile on mac
+    // vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
+
+    // END CLOUDS
 }
-
diff --git a/indra/newview/app_settings/shaders/class1/deferred/fullbrightShinyF.glsl b/indra/newview/app_settings/shaders/class1/deferred/fullbrightShinyF.glsl
index bd0ad3bce8..6b36d00f97 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/fullbrightShinyF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/fullbrightShinyF.glsl
@@ -42,6 +42,9 @@ VARYING vec4 vary_position;
 
 uniform samplerCube environmentMap;
 
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO; used in LLDrawPoolAlpha::beginRenderPass()
+uniform int no_atmo;
+
 vec3 fullbrightShinyAtmosTransport(vec3 light);
 vec3 fullbrightAtmosTransportFrag(vec3 light, vec3 additive, vec3 atten);
 vec3 fullbrightScaleSoftClip(vec3 light);
@@ -51,7 +54,9 @@ void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, ou
 vec3 linear_to_srgb(vec3 c);
 vec3 srgb_to_linear(vec3 c);
 
-
+// See:
+//   class1\deferred\fullbrightShinyF.glsl
+//   class1\lighting\lightFullbrightShinyF.glsl
 void main()
 {
 #ifdef HAS_DIFFUSE_LOOKUP
@@ -59,25 +64,39 @@ void main()
 #else
 	vec4 color = texture2D(diffuseMap, vary_texcoord0.xy);
 #endif
-	
+
 	color.rgb *= vertex_color.rgb;
-	vec3 pos = vary_position.xyz/vary_position.w;
 
-	vec3 sunlit;
-	vec3 amblit;
-	vec3 additive;
-	vec3 atten;
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 0)
+	{
+		vec3 sunlit;
+		vec3 amblit;
+		vec3 additive;
+		vec3 atten;
+		vec3 pos = vary_position.xyz/vary_position.w;
+
+		calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten, false);
 
-	calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten, false);
-	
-	vec3 envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;	
-	float env_intensity = vertex_color.a;
-	color.rgb = mix(color.rgb, envColor.rgb, env_intensity);
+		vec3 envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;
+		float env_intensity = vertex_color.a;
 
 	//color.rgb = srgb_to_linear(color.rgb);
-	
-	color.rgb = fullbrightAtmosTransportFrag(color.rgb, additive, atten);
-	color.rgb = fullbrightScaleSoftClip(color.rgb);
+		color.rgb = mix(color.rgb, envColor.rgb, env_intensity);
+
+		color.rgb = fullbrightAtmosTransportFrag(color.rgb, additive, atten);
+		color.rgb = fullbrightScaleSoftClip(color.rgb);
+	}
+
+/*
+	// NOTE: HUD objects will be full bright. Uncomment if you want "some" environment lighting effecting these HUD objects.
+	else
+	{
+		vec3  envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;
+		float env_intensity = vertex_color.a;
+		color.rgb = mix(color.rgb, envColor.rgb, env_intensity);
+	}
+*/
 
 	color.a = 1.0;
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl b/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
index 0afd1a9672..80d19102b6 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
@@ -1,439 +1,443 @@
-/**

-* @file materialF.glsl

-*

-* $LicenseInfo:firstyear=2007&license=viewerlgpl$

-* Second Life Viewer Source Code

-* Copyright (C) 2007, Linden Research, Inc.

-*

-* This library is free software; you can redistribute it and/or

-* modify it under the terms of the GNU Lesser General Public

-* License as published by the Free Software Foundation;

-* version 2.1 of the License only.

-*

-* This library is distributed in the hope that it will be useful,

-* but WITHOUT ANY WARRANTY; without even the implied warranty of

-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

-* Lesser General Public License for more details.

-*

-* You should have received a copy of the GNU Lesser General Public

-* License along with this library; if not, write to the Free Software

-* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

-*

-* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA

-* $/LicenseInfo$

-*/

-

-/*[EXTRA_CODE_HERE]*/

-

-//class1/deferred/materialF.glsl

-

-// This shader is used for both writing opaque/masked content to the gbuffer and writing blended content to the framebuffer during the alpha pass.

-

-#define DIFFUSE_ALPHA_MODE_NONE     0

-#define DIFFUSE_ALPHA_MODE_BLEND    1

-#define DIFFUSE_ALPHA_MODE_MASK     2

-#define DIFFUSE_ALPHA_MODE_EMISSIVE 3

-

-uniform float emissive_brightness;  // fullbright flag, 1.0 == fullbright, 0.0 otherwise

-uniform int sun_up_factor;

-

-#ifdef WATER_FOG

-vec4 applyWaterFogView(vec3 pos, vec4 color);

-#endif

-

-vec3 atmosFragLighting(vec3 l, vec3 additive, vec3 atten);

-vec3 scaleSoftClipFrag(vec3 l);

-

-vec3 fullbrightAtmosTransportFrag(vec3 light, vec3 additive, vec3 atten);

-vec3 fullbrightScaleSoftClip(vec3 light);

-

-void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);

-

-vec3 srgb_to_linear(vec3 cs);

-vec3 linear_to_srgb(vec3 cs);

-

-#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)

-

-#ifdef DEFINE_GL_FRAGCOLOR

-out vec4 frag_color;

-#else

-#define frag_color gl_FragColor

-#endif

-

-#ifdef HAS_SUN_SHADOW

-float sampleDirectionalShadow(vec3 pos, vec3 norm, vec2 pos_screen);

-#endif

-

-uniform samplerCube environmentMap;

-uniform sampler2D     lightFunc;

-

-// Inputs

-uniform vec4 morphFactor;

-uniform vec3 camPosLocal;

-uniform mat3 env_mat;

-

-uniform vec3 sun_dir;

-uniform vec3 moon_dir;

-VARYING vec2 vary_fragcoord;

-

-VARYING vec3 vary_position;

-

-uniform mat4 proj_mat;

-uniform mat4 inv_proj;

-uniform vec2 screen_res;

-

-uniform vec4 light_position[8];

-uniform vec3 light_direction[8];

-uniform vec4 light_attenuation[8];

-uniform vec3 light_diffuse[8];

-

-float getAmbientClamp();

-

-vec3 calcPointLightOrSpotLight(vec3 light_col, vec3 npos, vec3 diffuse, vec4 spec, vec3 v, vec3 n, vec4 lp, vec3 ln, float la, float fa, float is_pointlight, inout float glare, float ambiance)

-{

-    vec3 col = vec3(0);

-

-    //get light vector

-    vec3 lv = lp.xyz - v;

-

-    //get distance

-    float dist = length(lv);

-    float da = 1.0;

-

-    dist /= la;

-

-    if (dist > 0.0 && la > 0.0)

-    {

-        //normalize light vector

-        lv = normalize(lv);

-

-        //distance attenuation

-        float dist_atten = clamp(1.0 - (dist - 1.0*(1.0 - fa)) / fa, 0.0, 1.0);

-        dist_atten *= dist_atten;

-        dist_atten *= 2.0f;

-

-        if (dist_atten <= 0.0)

-        {

-            return col;

-        }

-

-        // spotlight coefficient.

-        float spot = max(dot(-ln, lv), is_pointlight);

-        da *= spot*spot; // GL_SPOT_EXPONENT=2

-

-        //angular attenuation

-        da *= dot(n, lv);

-

-        float lit = 0.0f;

-

-        float amb_da = ambiance;

-        if (da >= 0)

-        {

-            lit = max(da * dist_atten, 0.0);

-            col = lit * light_col * diffuse;

-            amb_da += (da*0.5 + 0.5) * ambiance;

-        }

-        amb_da += (da*da*0.5 + 0.5) * ambiance;

-        amb_da *= dist_atten;

-        amb_da = min(amb_da, 1.0f - lit);

-

-        // SL-10969 need to see why these are blown out

-        //col.rgb += amb_da * light_col * diffuse;

-

-        if (spec.a > 0.0)

-        {

-            //vec3 ref = dot(pos+lv, norm);

-            vec3 h = normalize(lv + npos);

-            float nh = dot(n, h);

-            float nv = dot(n, npos);

-            float vh = dot(npos, h);

-            float sa = nh;

-            float fres = pow(1 - dot(h, npos), 5)*0.4 + 0.5;

-

-            float gtdenom = 2 * nh;

-            float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));

-

-            if (nh > 0.0)

-            {

-                float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt / (nh*da);

-                vec3 speccol = lit*scol*light_col.rgb*spec.rgb;

-                speccol = clamp(speccol, vec3(0), vec3(1));

-                col += speccol;

-

-                float cur_glare = max(speccol.r, speccol.g);

-                cur_glare = max(cur_glare, speccol.b);

-                glare = max(glare, speccol.r);

-                glare += max(cur_glare, 0.0);

-            }

-        }

-    }

-

-    return max(col, vec3(0.0, 0.0, 0.0));

-}

-

-#else

-#ifdef DEFINE_GL_FRAGCOLOR

-out vec4 frag_data[3];

-#else

-#define frag_data gl_FragData

-#endif

-#endif

-

-uniform sampler2D diffuseMap;  //always in sRGB space

-

-#ifdef HAS_NORMAL_MAP

-uniform sampler2D bumpMap;

-#endif

-

-#ifdef HAS_SPECULAR_MAP

-uniform sampler2D specularMap;

-

-VARYING vec2 vary_texcoord2;

-#endif

-

-uniform float env_intensity;

-uniform vec4 specular_color;  // specular color RGB and specular exponent (glossiness) in alpha

-

-#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_MASK)

-uniform float minimum_alpha;

-#endif

-

-#ifdef HAS_NORMAL_MAP

-VARYING vec3 vary_mat0;

-VARYING vec3 vary_mat1;

-VARYING vec3 vary_mat2;

-VARYING vec2 vary_texcoord1;

-#else

-VARYING vec3 vary_normal;

-#endif

-

-VARYING vec4 vertex_color;

-VARYING vec2 vary_texcoord0;

-

-vec2 encode_normal(vec3 n);

-

-void main()

-{

-    vec2 pos_screen = vary_texcoord0.xy;

-

-    vec4 diffcol = texture2D(diffuseMap, vary_texcoord0.xy);

-	diffcol.rgb *= vertex_color.rgb;

-

-#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_MASK)

-

-    // Comparing floats cast from 8-bit values, produces acne right at the 8-bit transition points

-    float bias = 0.001953125; // 1/512, or half an 8-bit quantization

-    if (diffcol.a < minimum_alpha-bias)

-    {

-        discard;

-    }

-#endif

-

-#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)

-	vec3 gamma_diff = diffcol.rgb;

-	diffcol.rgb = srgb_to_linear(diffcol.rgb);

-#endif

-

-#ifdef HAS_SPECULAR_MAP

-    vec4 spec = texture2D(specularMap, vary_texcoord2.xy);

-    spec.rgb *= specular_color.rgb;

-#else

-    vec4 spec = vec4(specular_color.rgb, 1.0);

-#endif

-

-#ifdef HAS_NORMAL_MAP

-	vec4 norm = texture2D(bumpMap, vary_texcoord1.xy);

-

-	norm.xyz = norm.xyz * 2 - 1;

-

-	vec3 tnorm = vec3(dot(norm.xyz,vary_mat0),

-			  dot(norm.xyz,vary_mat1),

-			  dot(norm.xyz,vary_mat2));

-#else

-	vec4 norm = vec4(0,0,0,1.0);

-	vec3 tnorm = vary_normal;

-#endif

-

-    norm.xyz = normalize(tnorm.xyz);

-

-    vec2 abnormal = encode_normal(norm.xyz);

-

-    vec4 final_color = diffcol;

-

-#if (DIFFUSE_ALPHA_MODE != DIFFUSE_ALPHA_MODE_EMISSIVE)

-	final_color.a = emissive_brightness;

-#else

-	final_color.a = max(final_color.a, emissive_brightness);

-#endif

-

-    vec4 final_specular = spec;

-    

-#ifdef HAS_SPECULAR_MAP

-    vec4 final_normal = vec4(encode_normal(normalize(tnorm)), env_intensity * spec.a, 0.0);

-	final_specular.a = specular_color.a * norm.a;

-#else

-	vec4 final_normal = vec4(encode_normal(normalize(tnorm)), env_intensity, 0.0);

-	final_specular.a = specular_color.a;

-#endif

-

-#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)

-

-    //forward rendering, output just lit sRGBA

-    vec3 pos = vary_position;

-

-    float shadow = 1.0f;

-

-#ifdef HAS_SUN_SHADOW

-    shadow = sampleDirectionalShadow(pos.xyz, norm.xyz, pos_screen);

-#endif

-

-    spec = final_specular;

-    vec4 diffuse = final_color;

-    float envIntensity = final_normal.z;

-

-    vec3 color = vec3(0,0,0);

-

-    vec3 light_dir = (sun_up_factor == 1) ? sun_dir : moon_dir;

-

-    float bloom = 0.0;

-    vec3 sunlit;

-    vec3 amblit;

-    vec3 additive;

-    vec3 atten;

-

-    calcAtmosphericVars(pos.xyz, light_dir, 1.0, sunlit, amblit, additive, atten, false);

-    

-        // This call breaks the Mac GLSL compiler/linker for unknown reasons (17Mar2020)

-        // The call is either a no-op or a pure (pow) gamma adjustment, depending on GPU level

-        // TODO: determine if we want to re-apply the gamma adjustment, and if so understand & fix Mac breakage

-        //color = fullbrightScaleSoftClip(color);

-

-    vec3 refnormpersp = normalize(reflect(pos.xyz, norm.xyz));

-

-    //we're in sRGB space, so gamma correct this dot product so 

-    // lighting from the sun stays sharp

-    float da = clamp(dot(normalize(norm.xyz), light_dir.xyz), 0.0, 1.0);

-    da = pow(da, 1.0 / 1.3);

-

-    color = amblit;

-

-    //darken ambient for normals perpendicular to light vector so surfaces in shadow 

-    // and facing away from light still have some definition to them.

-    // do NOT gamma correct this dot product so ambient lighting stays soft

-    float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);

-    ambient *= 0.5;

-    ambient *= ambient;

-    ambient = (1.0 - ambient);

-

-    vec3 sun_contrib = min(da, shadow) * sunlit;

-    

-    color *= ambient;

-

-    color += sun_contrib;

-

-    color *= gamma_diff.rgb;

-

-    float glare = 0.0;

-

-    if (spec.a > 0.0) // specular reflection

-    {

-#if 1 //EEP

-

-        vec3 npos = -normalize(pos.xyz);

-

-        //vec3 ref = dot(pos+lv, norm);

-        vec3 h = normalize(light_dir.xyz + npos);

-        float nh = dot(norm.xyz, h);

-        float nv = dot(norm.xyz, npos);

-        float vh = dot(npos, h);

-        float sa = nh;

-        float fres = pow(1 - dot(h, npos), 5)*0.4 + 0.5;

-

-        float gtdenom = 2 * nh;

-        float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));

-

-        if (nh > 0.0)

-        {

-            float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt / (nh*da);

-            vec3 sp = sun_contrib*scol / 6.0f;

-            sp = clamp(sp, vec3(0), vec3(1));

-            bloom = dot(sp, sp) / 4.0;

-            color += sp * spec.rgb;

-        }

-#else // PRODUCTION

-        float sa = dot(refnormpersp, sun_dir.xyz);

-		vec3 dumbshiny = sunlit*shadow*(texture2D(lightFunc, vec2(sa, spec.a)).r);

-							

-		// add the two types of shiny together

-		vec3 spec_contrib = dumbshiny * spec.rgb;

-		bloom = dot(spec_contrib, spec_contrib) / 6;

-

-		glare = max(spec_contrib.r, spec_contrib.g);

-		glare = max(glare, spec_contrib.b);

-

-		color += spec_contrib;

-#endif

-    }

-

-    color = mix(color.rgb, diffcol.rgb, diffuse.a);

-    

-    if (envIntensity > 0.0)

-    {

-        //add environmentmap

-        vec3 env_vec = env_mat * refnormpersp;

-

-        vec3 reflected_color = textureCube(environmentMap, env_vec).rgb;

-

-        color = mix(color, reflected_color, envIntensity);

-

-        float cur_glare = max(reflected_color.r, reflected_color.g);

-        cur_glare = max(cur_glare, reflected_color.b);

-        cur_glare *= envIntensity*4.0;

-        glare += cur_glare;

-    }

-

-    color = atmosFragLighting(color, additive, atten);

-    color = scaleSoftClipFrag(color);

-

-    //convert to linear before adding local lights

-    color = srgb_to_linear(color);

-

-    vec3 npos = normalize(-pos.xyz);

-

-    vec3 light = vec3(0, 0, 0);

-    

-#define LIGHT_LOOP(i) light.rgb += calcPointLightOrSpotLight(light_diffuse[i].rgb, npos, diffuse.rgb, final_specular, pos.xyz, norm.xyz, light_position[i], light_direction[i].xyz, light_attenuation[i].x, light_attenuation[i].y, light_attenuation[i].z, glare, light_attenuation[i].w );

-

-    LIGHT_LOOP(1)

-        LIGHT_LOOP(2)

-        LIGHT_LOOP(3)

-        LIGHT_LOOP(4)

-        LIGHT_LOOP(5)

-        LIGHT_LOOP(6)

-        LIGHT_LOOP(7)

-

-    color += light;

-

-    glare = min(glare, 1.0);

-    float al = max(diffcol.a, glare)*vertex_color.a;

-

-    //convert to srgb as this color is being written post gamma correction

-    color = linear_to_srgb(color);

-

-#ifdef WATER_FOG

-    vec4 temp = applyWaterFogView(pos, vec4(color, al));

-    color = temp.rgb;

-    al = temp.a;

-#endif

-

-    frag_color = vec4(color, al);

-

-#else // mode is not DIFFUSE_ALPHA_MODE_BLEND, encode to gbuffer 

-

-    // deferred path

-    frag_data[0] = final_color; //gbuffer is sRGB

-    frag_data[1] = final_specular; // XYZ = Specular color. W = Specular exponent.

-    frag_data[2] = final_normal; // XY = Normal.  Z = Env. intensity.

-#endif

-}

-

+/**
+* @file materialF.glsl
+*
+* $LicenseInfo:firstyear=2007&license=viewerlgpl$
+* Second Life Viewer Source Code
+* Copyright (C) 2007, Linden Research, Inc.
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation;
+* version 2.1 of the License only.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*
+* Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+* $/LicenseInfo$
+*/
+
+/*[EXTRA_CODE_HERE]*/
+
+//class1/deferred/materialF.glsl
+
+// This shader is used for both writing opaque/masked content to the gbuffer and writing blended content to the framebuffer during the alpha pass.
+
+#define DIFFUSE_ALPHA_MODE_NONE     0
+#define DIFFUSE_ALPHA_MODE_BLEND    1
+#define DIFFUSE_ALPHA_MODE_MASK     2
+#define DIFFUSE_ALPHA_MODE_EMISSIVE 3
+
+uniform float emissive_brightness;  // fullbright flag, 1.0 == fullbright, 0.0 otherwise
+uniform int sun_up_factor;
+
+#ifdef WATER_FOG
+vec4 applyWaterFogView(vec3 pos, vec4 color);
+#endif
+
+vec3 atmosFragLighting(vec3 l, vec3 additive, vec3 atten);
+vec3 scaleSoftClipFrag(vec3 l);
+
+vec3 fullbrightAtmosTransportFrag(vec3 light, vec3 additive, vec3 atten);
+vec3 fullbrightScaleSoftClip(vec3 light);
+
+void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);
+
+vec3 srgb_to_linear(vec3 cs);
+vec3 linear_to_srgb(vec3 cs);
+
+#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)
+
+#ifdef DEFINE_GL_FRAGCOLOR
+out vec4 frag_color;
+#else
+#define frag_color gl_FragColor
+#endif
+
+#ifdef HAS_SUN_SHADOW
+float sampleDirectionalShadow(vec3 pos, vec3 norm, vec2 pos_screen);
+#endif
+
+uniform samplerCube environmentMap;
+uniform sampler2D     lightFunc;
+
+// Inputs
+uniform vec4 morphFactor;
+uniform vec3 camPosLocal;
+uniform mat3 env_mat;
+
+uniform vec3 sun_dir;
+uniform vec3 moon_dir;
+VARYING vec2 vary_fragcoord;
+
+VARYING vec3 vary_position;
+
+uniform mat4 proj_mat;
+uniform mat4 inv_proj;
+uniform vec2 screen_res;
+
+uniform vec4 light_position[8];
+uniform vec3 light_direction[8];
+uniform vec4 light_attenuation[8];
+uniform vec3 light_diffuse[8];
+
+float getAmbientClamp();
+
+vec3 calcPointLightOrSpotLight(vec3 light_col, vec3 npos, vec3 diffuse, vec4 spec, vec3 v, vec3 n, vec4 lp, vec3 ln, float la, float fa, float is_pointlight, inout float glare, float ambiance)
+{
+    vec3 col = vec3(0);
+
+    //get light vector
+    vec3 lv = lp.xyz - v;
+
+    //get distance
+    float dist = length(lv);
+    float da = 1.0;
+
+    dist /= la;
+
+    if (dist > 0.0 && la > 0.0)
+    {
+        //normalize light vector
+        lv = normalize(lv);
+
+        //distance attenuation
+        float dist_atten = clamp(1.0 - (dist - 1.0*(1.0 - fa)) / fa, 0.0, 1.0);
+        dist_atten *= dist_atten;
+        dist_atten *= 2.0f;
+
+        if (dist_atten <= 0.0)
+        {
+            return col;
+        }
+
+        // spotlight coefficient.
+        float spot = max(dot(-ln, lv), is_pointlight);
+        da *= spot*spot; // GL_SPOT_EXPONENT=2
+
+        //angular attenuation
+        da *= dot(n, lv);
+
+        float lit = 0.0f;
+
+        float amb_da = ambiance;
+        if (da >= 0)
+        {
+            lit = max(da * dist_atten, 0.0);
+            col = lit * light_col * diffuse;
+            amb_da += (da*0.5 + 0.5) * ambiance;
+        }
+        amb_da += (da*da*0.5 + 0.5) * ambiance;
+        amb_da *= dist_atten;
+        amb_da = min(amb_da, 1.0f - lit);
+
+        // SL-10969 need to see why these are blown out
+        //col.rgb += amb_da * light_col * diffuse;
+
+        if (spec.a > 0.0)
+        {
+            //vec3 ref = dot(pos+lv, norm);
+            vec3 h = normalize(lv + npos);
+            float nh = dot(n, h);
+            float nv = dot(n, npos);
+            float vh = dot(npos, h);
+            float sa = nh;
+            float fres = pow(1 - dot(h, npos), 5)*0.4 + 0.5;
+
+            float gtdenom = 2 * nh;
+            float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
+
+            if (nh > 0.0)
+            {
+                float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt / (nh*da);
+                vec3 speccol = lit*scol*light_col.rgb*spec.rgb;
+                speccol = clamp(speccol, vec3(0), vec3(1));
+                col += speccol;
+
+                float cur_glare = max(speccol.r, speccol.g);
+                cur_glare = max(cur_glare, speccol.b);
+                glare = max(glare, speccol.r);
+                glare += max(cur_glare, 0.0);
+            }
+        }
+    }
+
+    return max(col, vec3(0.0, 0.0, 0.0));
+}
+
+#else
+#ifdef DEFINE_GL_FRAGCOLOR
+out vec4 frag_data[3];
+#else
+#define frag_data gl_FragData
+#endif
+#endif
+
+uniform sampler2D diffuseMap;  //always in sRGB space
+
+#ifdef HAS_NORMAL_MAP
+uniform sampler2D bumpMap;
+#endif
+
+#ifdef HAS_SPECULAR_MAP
+uniform sampler2D specularMap;
+
+VARYING vec2 vary_texcoord2;
+#endif
+
+uniform float env_intensity;
+uniform vec4 specular_color;  // specular color RGB and specular exponent (glossiness) in alpha
+
+#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_MASK)
+uniform float minimum_alpha;
+#endif
+
+#ifdef HAS_NORMAL_MAP
+VARYING vec3 vary_mat0;
+VARYING vec3 vary_mat1;
+VARYING vec3 vary_mat2;
+VARYING vec2 vary_texcoord1;
+#else
+VARYING vec3 vary_normal;
+#endif
+
+VARYING vec4 vertex_color;
+VARYING vec2 vary_texcoord0;
+
+vec2 encode_normal(vec3 n);
+
+void main()
+{
+    vec2 pos_screen = vary_texcoord0.xy;
+
+    vec4 diffcol = texture2D(diffuseMap, vary_texcoord0.xy);
+	diffcol.rgb *= vertex_color.rgb;
+
+#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_MASK)
+
+    // Comparing floats cast from 8-bit values, produces acne right at the 8-bit transition points
+    float bias = 0.001953125; // 1/512, or half an 8-bit quantization
+    if (diffcol.a < minimum_alpha-bias)
+    {
+        discard;
+    }
+#endif
+
+#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)
+	vec3 gamma_diff = diffcol.rgb;
+	diffcol.rgb = srgb_to_linear(diffcol.rgb);
+#endif
+
+#ifdef HAS_SPECULAR_MAP
+    vec4 spec = texture2D(specularMap, vary_texcoord2.xy);
+    spec.rgb *= specular_color.rgb;
+#else
+    vec4 spec = vec4(specular_color.rgb, 1.0);
+#endif
+
+#ifdef HAS_NORMAL_MAP
+	vec4 norm = texture2D(bumpMap, vary_texcoord1.xy);
+
+	norm.xyz = norm.xyz * 2 - 1;
+
+	vec3 tnorm = vec3(dot(norm.xyz,vary_mat0),
+			  dot(norm.xyz,vary_mat1),
+			  dot(norm.xyz,vary_mat2));
+#else
+	vec4 norm = vec4(0,0,0,1.0);
+	vec3 tnorm = vary_normal;
+#endif
+
+    norm.xyz = normalize(tnorm.xyz);
+
+    vec2 abnormal = encode_normal(norm.xyz);
+
+    vec4 final_color = diffcol;
+
+#if (DIFFUSE_ALPHA_MODE != DIFFUSE_ALPHA_MODE_EMISSIVE)
+	final_color.a = emissive_brightness;
+#else
+	final_color.a = max(final_color.a, emissive_brightness);
+#endif
+
+    vec4 final_specular = spec;
+    
+#ifdef HAS_SPECULAR_MAP
+    vec4 final_normal = vec4(encode_normal(normalize(tnorm)), env_intensity * spec.a, 0.0);
+	final_specular.a = specular_color.a * norm.a;
+#else
+	vec4 final_normal = vec4(encode_normal(normalize(tnorm)), env_intensity, 0.0);
+	final_specular.a = specular_color.a;
+#endif
+
+#if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)
+
+    //forward rendering, output just lit sRGBA
+    vec3 pos = vary_position;
+
+    float shadow = 1.0f;
+
+#ifdef HAS_SUN_SHADOW
+    shadow = sampleDirectionalShadow(pos.xyz, norm.xyz, pos_screen);
+#endif
+
+    spec = final_specular;
+    vec4 diffuse = final_color;
+    float envIntensity = final_normal.z;
+
+    vec3 color = vec3(0,0,0);
+
+    vec3 light_dir = (sun_up_factor == 1) ? sun_dir : moon_dir;
+
+    float bloom = 0.0;
+    vec3 sunlit;
+    vec3 amblit;
+    vec3 additive;
+    vec3 atten;
+
+    calcAtmosphericVars(pos.xyz, light_dir, 1.0, sunlit, amblit, additive, atten, false);
+    
+        // This call breaks the Mac GLSL compiler/linker for unknown reasons (17Mar2020)
+        // The call is either a no-op or a pure (pow) gamma adjustment, depending on GPU level
+        // TODO: determine if we want to re-apply the gamma adjustment, and if so understand & fix Mac breakage
+        //color = fullbrightScaleSoftClip(color);
+
+    vec3 refnormpersp = normalize(reflect(pos.xyz, norm.xyz));
+
+    //we're in sRGB space, so gamma correct this dot product so 
+    // lighting from the sun stays sharp
+    float da = clamp(dot(normalize(norm.xyz), light_dir.xyz), 0.0, 1.0);
+    da = pow(da, 1.0 / 1.3);
+
+    color = amblit;
+
+    //darken ambient for normals perpendicular to light vector so surfaces in shadow 
+    // and facing away from light still have some definition to them.
+    // do NOT gamma correct this dot product so ambient lighting stays soft
+    float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);
+    ambient *= 0.5;
+    ambient *= ambient;
+    ambient = (1.0 - ambient);
+
+    vec3 sun_contrib = min(da, shadow) * sunlit;
+    
+    color *= ambient;
+
+    color += sun_contrib;
+
+    color *= gamma_diff.rgb;
+
+    float glare = 0.0;
+
+    if (spec.a > 0.0)  // specular reflection
+    {
+        /*  // Reverting this specular calculation to previous 'dumbshiny' version - DJH 6/17/2020
+            // Preserving the refactored version as a comment for potential reconsideration,
+            // overriding the general rule to avoid pollutiong the source with commented code.
+            //
+            //  If you're reading this in 2021+, feel free to obliterate.
+
+        vec3 npos = -normalize(pos.xyz);
+
+        //vec3 ref = dot(pos+lv, norm);
+        vec3 h = normalize(light_dir.xyz + npos);
+        float nh = dot(norm.xyz, h);
+        float nv = dot(norm.xyz, npos);
+        float vh = dot(npos, h);
+        float sa = nh;
+        float fres = pow(1 - dot(h, npos), 5)*0.4 + 0.5;
+
+        float gtdenom = 2 * nh;
+        float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
+
+        if (nh > 0.0)
+        {
+            float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt / (nh*da);
+            vec3 sp = sun_contrib*scol / 6.0f;
+            sp = clamp(sp, vec3(0), vec3(1));
+            bloom = dot(sp, sp) / 4.0;
+            color += sp * spec.rgb;
+        }
+        */
+
+        float sa        = dot(refnormpersp, sun_dir.xyz);
+        vec3  dumbshiny = sunlit * shadow * (texture2D(lightFunc, vec2(sa, spec.a)).r);
+
+        // add the two types of shiny together
+        vec3 spec_contrib = dumbshiny * spec.rgb;
+        bloom             = dot(spec_contrib, spec_contrib) / 6;
+
+        glare = max(spec_contrib.r, spec_contrib.g);
+        glare = max(glare, spec_contrib.b);
+
+        color += spec_contrib;
+    }
+
+    color = mix(color.rgb, diffcol.rgb, diffuse.a);
+
+    if (envIntensity > 0.0)
+    {
+        //add environmentmap
+        vec3 env_vec = env_mat * refnormpersp;
+
+        vec3 reflected_color = textureCube(environmentMap, env_vec).rgb;
+
+        color = mix(color, reflected_color, envIntensity);
+
+        float cur_glare = max(reflected_color.r, reflected_color.g);
+        cur_glare = max(cur_glare, reflected_color.b);
+        cur_glare *= envIntensity*4.0;
+        glare += cur_glare;
+    }
+
+    color = atmosFragLighting(color, additive, atten);
+    color = scaleSoftClipFrag(color);
+
+    //convert to linear before adding local lights
+    color = srgb_to_linear(color);
+
+    vec3 npos = normalize(-pos.xyz);
+
+    vec3 light = vec3(0, 0, 0);
+    
+#define LIGHT_LOOP(i) light.rgb += calcPointLightOrSpotLight(light_diffuse[i].rgb, npos, diffuse.rgb, final_specular, pos.xyz, norm.xyz, light_position[i], light_direction[i].xyz, light_attenuation[i].x, light_attenuation[i].y, light_attenuation[i].z, glare, light_attenuation[i].w );
+
+    LIGHT_LOOP(1)
+        LIGHT_LOOP(2)
+        LIGHT_LOOP(3)
+        LIGHT_LOOP(4)
+        LIGHT_LOOP(5)
+        LIGHT_LOOP(6)
+        LIGHT_LOOP(7)
+
+    color += light;
+
+    glare = min(glare, 1.0);
+    float al = max(diffcol.a, glare)*vertex_color.a;
+
+    //convert to srgb as this color is being written post gamma correction
+    color = linear_to_srgb(color);
+
+#ifdef WATER_FOG
+    vec4 temp = applyWaterFogView(pos, vec4(color, al));
+    color = temp.rgb;
+    al = temp.a;
+#endif
+
+    frag_color = vec4(color, al);
+
+#else // mode is not DIFFUSE_ALPHA_MODE_BLEND, encode to gbuffer 
+
+    // deferred path
+    frag_data[0] = final_color; //gbuffer is sRGB
+    frag_data[1] = final_specular; // XYZ = Specular color. W = Specular exponent.
+    frag_data[2] = final_normal; // XY = Normal.  Z = Env. intensity.
+#endif
+}
+
diff --git a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
index 80f232948a..35068899ee 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
@@ -1,9 +1,9 @@
 /** 
- * @file moonF.glsl
+ * @file class1\deferred\moonF.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2005, Linden Research, Inc.
+ * Copyright (C) 2005, 2020 Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -36,34 +36,33 @@ out vec4 frag_data[3];
 uniform vec4 color;
 uniform vec4 sunlight_color;
 uniform vec4 moonlight_color;
-uniform vec3 lumWeights;
+uniform vec3 moon_dir;
 uniform float moon_brightness;
-uniform float minLuminance;
 uniform sampler2D diffuseMap;
-uniform sampler2D altDiffuseMap;
-uniform float blend_factor; // interp factor between moon A/B
+
 VARYING vec2 vary_texcoord0;
 
 vec3 srgb_to_linear(vec3 c);
-void main() 
-{
-    vec4 moonA = texture2D(diffuseMap, vary_texcoord0.xy);
-    vec4 moonB = texture2D(altDiffuseMap, vary_texcoord0.xy);
-    vec4 c     = mix(moonA, moonB, blend_factor);
 
-    c.rgb = srgb_to_linear(c.rgb);
+/// Soft clips the light with a gamma correction
+vec3 scaleSoftClip(vec3 light);
 
-    // mix factor which blends when sunlight is brighter
-    // and shows true moon color at night
-    vec3 luma_weights = vec3(0.3, 0.5, 0.3);
+void main() 
+{
+    // Restore Pre-EEP alpha fade moon near horizon
+    float fade = 1.0;
+    if( moon_dir.z > 0 )
+        fade = clamp( moon_dir.z*moon_dir.z*4.0, 0.0, 1.0 );
 
-    vec4 light_color = max(sunlight_color, moonlight_color);
-    float mix = 1.0 - dot(normalize(light_color.rgb), luma_weights);
+    vec4 c      = texture2D(diffuseMap, vary_texcoord0.xy);
+//       c.rgb  = srgb_to_linear(c.rgb);
+         c.rgb *= moonlight_color.rgb;
+         c.rgb *= moon_brightness;
 
-    vec3 exp = vec3(1.0 - mix * moon_brightness) * 2.0  - 1.0;
-    c.rgb = pow(c.rgb, exp);
+         c.rgb *= fade;
+         c.a   *= fade;
 
-    //c.rgb *= moonlight_color.rgb;
+         c.rgb  = scaleSoftClip(c.rgb);
 
     frag_data[0] = vec4(c.rgb, c.a);
     frag_data[1] = vec4(0.0);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/moonV.glsl b/indra/newview/app_settings/shaders/class1/deferred/moonV.glsl
index e1bac4f248..c4922afd7d 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/moonV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/moonV.glsl
@@ -1,9 +1,9 @@
 /** 
- * @file moonV.glsl
+ * @file class1\deferred\moonV.glsl
  *
   * $LicenseInfo:firstyear=2007&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2007, Linden Research, Inc.
+ * Copyright (C) 2007, 2020 Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -32,18 +32,13 @@ ATTRIBUTE vec2 texcoord0;
 
 VARYING vec2 vary_texcoord0;
 
-void calcAtmospherics(vec3 eye_pos);
-
 void main()
 {
     //transform vertex
-    vec3 offset = vec3(0, 0, 50);
-    vec4 vert = vec4(position.xyz - offset, 1.0);
+    vec4 vert = vec4(position.xyz, 1.0);
     vec4 pos = (modelview_matrix * vert);
 
     gl_Position = modelview_projection_matrix*vert;
 
-    calcAtmospherics(pos.xyz);
-    
     vary_texcoord0 = (texture_matrix0 * vec4(texcoord0,0,1)).xy;
 }
diff --git a/indra/newview/app_settings/shaders/class1/deferred/multiPointLightF.glsl b/indra/newview/app_settings/shaders/class1/deferred/multiPointLightF.glsl
index 0d1cc81786..8c402fcb54 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/multiPointLightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/multiPointLightF.glsl
@@ -1,24 +1,24 @@
-/** 
- * @file multiPointLightF.glsl
+/**
+ * @file class1/deferred/multiPointLightF.glsl
  *
  * $LicenseInfo:firstyear=2007&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2007, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -36,119 +36,112 @@ out vec4 frag_color;
 uniform sampler2DRect depthMap;
 uniform sampler2DRect diffuseRect;
 uniform sampler2DRect specularRect;
-uniform samplerCube environmentMap;
-uniform sampler2D noiseMap;
-uniform sampler2D lightFunc;
+uniform samplerCube   environmentMap;
+uniform sampler2D     noiseMap;
+uniform sampler2D     lightFunc;
 
-
-uniform vec3 env_mat[3];
+uniform vec3  env_mat[3];
 uniform float sun_wash;
+uniform int   light_count;
+uniform vec4  light[LIGHT_COUNT];
+uniform vec4  light_col[LIGHT_COUNT];
 
-uniform int light_count;
-
-uniform vec4 light[LIGHT_COUNT];
-uniform vec4 light_col[LIGHT_COUNT];
-
-VARYING vec4 vary_fragcoord;
-uniform vec2 screen_res;
-
+uniform vec2  screen_res;
 uniform float far_z;
+uniform mat4  inv_proj;
 
-uniform mat4 inv_proj;
+VARYING vec4 vary_fragcoord;
 
 vec4 getPosition(vec2 pos_screen);
 vec3 getNorm(vec2 pos_screen);
 vec3 srgb_to_linear(vec3 c);
 
-void main() 
+void main()
 {
-	vec3 out_col = vec3(0,0,0);
-
 #if defined(LOCAL_LIGHT_KILL)
-    discard;
-#else
-	vec2 frag = (vary_fragcoord.xy*0.5+0.5)*screen_res;
-	vec3 pos = getPosition(frag.xy).xyz;
-	if (pos.z < far_z)
-	{
-		discard;
-	}
-	
-	vec3 norm = getNorm(frag.xy);
-
-	vec4 spec = texture2DRect(specularRect, frag.xy);
-	vec3 diff = texture2DRect(diffuseRect, frag.xy).rgb;
-    diff.rgb = srgb_to_linear(diff.rgb);
-	
-	float noise = texture2D(noiseMap, frag.xy/128.0).b;
-	vec3 npos = normalize(-pos);
-
-	// As of OSX 10.6.7 ATI Apple's crash when using a variable size loop
-	for (int i = 0; i < LIGHT_COUNT; ++i)
-	{
-		vec3 lv = light[i].xyz-pos;
-		float dist = length(lv);
-		dist /= light[i].w;
-		if (dist <= 1.0)
-		{
-		float da = dot(norm, lv);
-			if (da > 0.0)
-		{
-			lv = normalize(lv);
-			da = dot(norm, lv);
-			
-			float fa = light_col[i].a+1.0;
-			float dist_atten = clamp(1.0-(dist-1.0*(1.0-fa))/fa, 0.0, 1.0);
-			dist_atten *= dist_atten;
-            
-            // Tweak falloff slightly to match pre-EEP attenuation
-			// NOTE: this magic number also shows up in a great many other places, search for dist_atten *= to audit
-			dist_atten *= 2.0;
-			
-			dist_atten *= noise;
-
-			float lit = da * dist_atten;
-						
-			vec3 col = light_col[i].rgb*lit*diff;
-			
-			//vec3 col = vec3(dist2, light_col[i].a, lit);
-			
-			if (spec.a > 0.0)
-			{
-				lit = min(da*6.0, 1.0) * dist_atten;
-				//vec3 ref = dot(pos+lv, norm);
-				vec3 h = normalize(lv+npos);
-				float nh = dot(norm, h);
-				float nv = dot(norm, npos);
-				float vh = dot(npos, h);
-				float sa = nh;
-				float fres = pow(1 - dot(h, npos), 5)*0.4+0.5;
-
-				float gtdenom = 2 * nh;
-				float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
-								
-				if (nh > 0.0)
-				{
-					float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt/(nh*da);
-					col += lit*scol*light_col[i].rgb*spec.rgb;
-					//col += spec.rgb;
-				}
-			}
-			
-			out_col += col;
-		}
-	}
-	}
+    discard;  // Bail immediately
 #endif
-	
-	frag_color.rgb = out_col;
-	frag_color.a = 0.0;
+
+    vec3 out_col = vec3(0, 0, 0);
+    vec2 frag    = (vary_fragcoord.xy * 0.5 + 0.5) * screen_res;
+    vec3 pos     = getPosition(frag.xy).xyz;
+    if (pos.z < far_z)
+    {
+        discard;
+    }
+
+    vec3 norm = getNorm(frag.xy);
+
+    vec4 spec = texture2DRect(specularRect, frag.xy);
+    spec.rgb  = srgb_to_linear(spec.rgb);
+    vec3 diff = texture2DRect(diffuseRect, frag.xy).rgb;
+    diff.rgb  = srgb_to_linear(diff.rgb);
+
+    float noise = texture2D(noiseMap, frag.xy / 128.0).b;
+    vec3  npos  = normalize(-pos);
+
+    // As of OSX 10.6.7 ATI Apple's crash when using a variable size loop
+    for (int i = 0; i < LIGHT_COUNT; ++i)
+    {
+        vec3  lv   = light[i].xyz - pos;
+        float dist = length(lv);
+        dist /= light[i].w;
+        if (dist <= 1.0)
+        {
+            float da = dot(norm, lv);
+            if (da > 0.0)
+            {
+                lv = normalize(lv);
+                da = dot(norm, lv);
+
+                float fa         = light_col[i].a + 1.0;
+                float dist_atten = clamp(1.0 - (dist - 1.0 * (1.0 - fa)) / fa, 0.0, 1.0);
+                dist_atten *= dist_atten;
+
+                // Tweak falloff slightly to match pre-EEP attenuation
+                // NOTE: this magic number also shows up in a great many other places, search for dist_atten *= to audit
+                dist_atten *= 2.0;
+
+                dist_atten *= noise;
+
+                float lit = da * dist_atten;
+
+                vec3 col = light_col[i].rgb * lit * diff;
+
+                if (spec.a > 0.0)
+                {
+                    lit        = min(da * 6.0, 1.0) * dist_atten;
+                    vec3  h    = normalize(lv + npos);
+                    float nh   = dot(norm, h);
+                    float nv   = dot(norm, npos);
+                    float vh   = dot(npos, h);
+                    float sa   = nh;
+                    float fres = pow(1 - dot(h, npos), 5) * 0.4 + 0.5;
+
+                    float gtdenom = 2 * nh;
+                    float gt      = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
+
+                    if (nh > 0.0)
+                    {
+                        float scol = fres * texture2D(lightFunc, vec2(nh, spec.a)).r * gt / (nh * da);
+                        col += lit * scol * light_col[i].rgb * spec.rgb;
+                    }
+                }
+
+                out_col += col;
+            }
+        }
+    }
+
+    frag_color.rgb = out_col;
+    frag_color.a   = 0.0;
 
 #ifdef IS_AMD_CARD
-	// If it's AMD make sure the GLSL compiler sees the arrays referenced once by static index. Otherwise it seems to optimise the storage awawy which leads to unfun crashes and artifacts.
-	vec4 dummy1 = light[0];
-	vec4 dummy2 = light_col[0];
-	vec4 dummy3 = light[LIGHT_COUNT-1];
-	vec4 dummy4 = light_col[LIGHT_COUNT-1];
+    // If it's AMD make sure the GLSL compiler sees the arrays referenced once by static index. Otherwise it seems to optimise the storage
+    // awawy which leads to unfun crashes and artifacts.
+    vec4 dummy1 = light[0];
+    vec4 dummy2 = light_col[0];
+    vec4 dummy3 = light[LIGHT_COUNT - 1];
+    vec4 dummy4 = light_col[LIGHT_COUNT - 1];
 #endif
 }
diff --git a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
index ead754ec76..28a1faf24f 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file WLSkyV.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2005, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -37,13 +37,13 @@ VARYING vec4 vary_HazeColor;
 // Inputs
 uniform vec3 camPosLocal;
 
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 
@@ -52,7 +52,7 @@ uniform float density_multiplier;
 uniform float distance_multiplier;
 uniform float max_y;
 
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float sun_moon_glow_factor;
 
 uniform vec4 cloud_color;
@@ -63,103 +63,91 @@ uniform vec4 cloud_color;
 //       indra\newview\lllegacyatmospherics.cpp
 void main()
 {
-
-	// World / view / projection
+    // World / view / projection
     vec4 pos = modelview_projection_matrix * vec4(position.xyz, 1.0);
 
-	gl_Position = pos;
-	
-	// Get relative position
-	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
-
-	// Set altitude
-	if (P.y > 0.)
-	{
-		P *= (max_y / P.y);
-	}
-	else
-	{
-		P *= (-32000. / P.y);
-	}
-
-	// Can normalize then
-	vec3 Pn = normalize(P);
-
-	float Plen = length(P);
-
-	// Initialize temp variables
-	vec4 temp1 = vec4(0.);
-	vec4 temp2 = vec4(0.);
-	vec4 blue_weight;
-	vec4 haze_weight;
-	vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-	vec4 light_atten;
-
-    float dens_mul = density_multiplier;
-
-	// Sunlight attenuation effect (hue and brightness) due to atmosphere
-	// this is used later for sunlight modulation at various altitudes
-	light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
-
-	// Calculate relative weights
-	temp1 = abs(blue_density) + vec4(abs(haze_density));
-	blue_weight = blue_density / temp1;
-	haze_weight = haze_density / temp1;
-
-	// Compute sunlight from P & lightnorm (for long rays like sky)
-    temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
-    temp2.y = 1. / temp2.y;
-    sunlight *= exp( - light_atten * temp2.y);
-
-	// Distance
-	temp2.z = Plen * dens_mul;
-
-	// Transparency (-> temp1)
-    // ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
-    // compiler gets confused.
-    temp1 = exp(-temp1 * temp2.z);
+    gl_Position = pos;
+
+    // Get relative position
+    vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0);
+
+    // Adj position vector to clamp altitude
+    if (rel_pos.y > 0)
+    {
+        rel_pos *= (max_y / rel_pos.y);
+    }
+    if (rel_pos.y < 0)
+    {
+        rel_pos *= (-32000. / rel_pos.y);
+    }
+
+    // Can normalize then
+    vec3 rel_pos_norm = normalize(rel_pos);
 
-	// Compute haze glow
-	temp2.x = dot(Pn, lightnorm.xyz);
-	temp2.x = 1. - temp2.x;
-		// temp2.x is 0 at the sun and increases away from sun
-	temp2.x = max(temp2.x, .001);	
-		// Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-	temp2.x *= glow.x;
-		// Higher glow.x gives dimmer glow (because next step is 1 / "angle")
-	temp2.x = pow(temp2.x, glow.z);
-		// glow.z should be negative, so we're doing a sort of (1 / "angle") function
+    float rel_pos_len = length(rel_pos);
 
-	// Add "minimum anti-solar illumination"
-	temp2.x += .25;
+    // Initialize temp variables
+    vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
+    vec4 light_atten;
 
-    vec4 color = (    blue_horizon * blue_weight * (sunlight + ambient_color)
-                + (haze_horizon * haze_weight) * (sunlight * temp2.x + ambient_color)
-             );
+    // Sunlight attenuation effect (hue and brightness) due to atmosphere
+    // this is used later for sunlight modulation at various altitudes
+    light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
 
+    // Calculate relative weights
+    vec4 combined_haze = abs(blue_density) + vec4(abs(haze_density));
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = haze_density / combined_haze;
+
+    // Compute sunlight from rel_pos & lightnorm (for long rays like sky)
+    float off_axis = 1.0 / max(1e-6, max(0., rel_pos_norm.y) + lightnorm.y);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Distance
+    float density_dist = rel_pos_len * density_multiplier;
+
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati
+    // compiler gets confused.
+    combined_haze = exp(-combined_haze * density_dist);
+
+    // Compute haze glow
+    float haze_glow = 1.0 - dot(rel_pos_norm, lightnorm.xyz);
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);
+    // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
+
+    // Add "minimum anti-solar illumination"
+    // For sun, add to glow.  For moon, remove glow entirely. SL-13768
+    haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (haze_glow + 0.25);
+
+    vec4 color =
+        (blue_horizon * blue_weight * (sunlight + ambient_color) + (haze_horizon * haze_weight) * (sunlight * haze_glow + ambient_color));
 
     // Final atmosphere additive
-    color *= (1. - temp1);
+    color *= (1. - combined_haze);
 
-	// Increase ambient when there are more clouds
-	vec4 tmpAmbient = ambient_color;
-	tmpAmbient += max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5; 
+    // Increase ambient when there are more clouds
+    vec4 tmpAmbient = ambient_color;
+    tmpAmbient += max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5;
 
-	// Dim sunlight by cloud shadow percentage
-	sunlight *= max(0.0, (1. - cloud_shadow));
+    // Dim sunlight by cloud shadow percentage
+    sunlight *= max(0.0, (1. - cloud_shadow));
 
-	// Haze color below cloud
-	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
-				+ (haze_horizon * haze_weight) * (sunlight * temp2.x + tmpAmbient)
-			 );	
+    // Haze color below cloud
+    vec4 additiveColorBelowCloud =
+        (blue_horizon * blue_weight * (sunlight + tmpAmbient) + (haze_horizon * haze_weight) * (sunlight * haze_glow + tmpAmbient));
 
-	// Attenuate cloud color by atmosphere
-	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
+    // Attenuate cloud color by atmosphere
+    combined_haze = sqrt(combined_haze);  // less atmos opacity (more transparency) below clouds
 
-	// At horizon, blend high altitude sky color towards the darker color below the clouds
-	color += (additiveColorBelowCloud - color) * (1. - sqrt(temp1));
+    // At horizon, blend high altitude sky color towards the darker color below the clouds
+    color += (additiveColorBelowCloud - color) * (1. - sqrt(combined_haze));
 
     // Haze color above cloud
-	vary_HazeColor = color;	
+    vary_HazeColor = color;
 }
-
diff --git a/indra/newview/app_settings/shaders/class1/deferred/softenLightF.glsl b/indra/newview/app_settings/shaders/class1/deferred/softenLightF.glsl
index a5804220bc..f80f1a985a 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/softenLightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/softenLightF.glsl
@@ -124,41 +124,15 @@ void main()
 
         if (spec.a > 0.0) // specular reflection
         {
+            float sa        = dot(refnormpersp, light_dir.xyz);
+            vec3  dumbshiny = sunlit * (texture2D(lightFunc, vec2(sa, spec.a)).r);
 
-#if 1 //EEP
-            vec3 npos = -normalize(pos.xyz);
-
-            //vec3 ref = dot(pos+lv, norm);
-            vec3 h = normalize(light_dir.xyz+npos);
-            float nh = dot(norm.xyz, h);
-            float nv = dot(norm.xyz, npos);
-            float vh = dot(npos, h);
-            float sa = nh;
-            float fres = pow(1 - dot(h, npos), 5)*0.4+0.5;
-
-            float gtdenom = 2 * nh;
-            float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
-            
-            if (nh > 0.0)
-            {
-                float scontrib = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt/(nh*da);
-                vec3 sp = sun_contrib*scontrib / 6.0;
-                sp = clamp(sp, vec3(0), vec3(1));
-                bloom += dot(sp, sp) / 4.0;
-                color += sp * spec.rgb;
-            }
-#else //PRODUCTION
-            float sa = dot(refnormpersp, light_dir.xyz);
-            vec3 dumbshiny = sunlit*(texture2D(lightFunc, vec2(sa, spec.a)).r);
-            
             // add the two types of shiny together
             vec3 spec_contrib = dumbshiny * spec.rgb;
-            bloom = dot(spec_contrib, spec_contrib) / 6;
+            bloom             = dot(spec_contrib, spec_contrib) / 6;
             color.rgb += spec_contrib;
-#endif
-
         }
-       
+
        color.rgb = mix(color.rgb, diffuse.rgb, diffuse.a);
 
         if (envIntensity > 0.0)
diff --git a/indra/newview/app_settings/shaders/class1/environment/encodeNormF.glsl b/indra/newview/app_settings/shaders/class1/environment/encodeNormF.glsl
index 50e781fa78..6cd2445522 100644
--- a/indra/newview/app_settings/shaders/class1/environment/encodeNormF.glsl
+++ b/indra/newview/app_settings/shaders/class1/environment/encodeNormF.glsl
@@ -23,6 +23,9 @@
  * $/LicenseInfo$
  */
 
+// Lambert Azimuthal Equal-Area projection
+// See: https://aras-p.info/texts/CompactNormalStorage.html
+// Also see: A_bit_more_deferred_-_CryEngine3.ppt
 vec2 encode_normal(vec3 n)
 {
 	float f = sqrt(8 * n.z + 8);
diff --git a/indra/newview/app_settings/shaders/class1/lighting/lightAlphaMaskF.glsl b/indra/newview/app_settings/shaders/class1/lighting/lightAlphaMaskF.glsl
index f665394b46..0bb48061e0 100644
--- a/indra/newview/app_settings/shaders/class1/lighting/lightAlphaMaskF.glsl
+++ b/indra/newview/app_settings/shaders/class1/lighting/lightAlphaMaskF.glsl
@@ -31,6 +31,9 @@ out vec4 frag_color;
 
 uniform float minimum_alpha;
 
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO;
+uniform int no_atmo;
+
 vec3 atmosLighting(vec3 light);
 vec3 scaleSoftClip(vec3 light);
 
@@ -41,16 +44,19 @@ void default_lighting()
 {
 	vec4 color = diffuseLookup(vary_texcoord0.xy);
 	
-	color *= vertex_color;
-
 	if (color.a < minimum_alpha)
 	{
 		discard;
 	}
+	
+	color *= vertex_color;
 
-	color.rgb = atmosLighting(color.rgb);
-
-	color.rgb = scaleSoftClip(color.rgb);
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 0)
+	{
+		color.rgb = atmosLighting(color.rgb);
+		color.rgb = scaleSoftClip(color.rgb);
+	}
 
 	frag_color = color;
 }
diff --git a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightAlphaMaskF.glsl b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightAlphaMaskF.glsl
index 46390e4a0e..1855cfceeb 100644
--- a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightAlphaMaskF.glsl
+++ b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightAlphaMaskF.glsl
@@ -30,7 +30,10 @@ out vec4 frag_color;
 #endif
 
 uniform float minimum_alpha;
-uniform float texture_gamma;
+uniform float texture_gamma; // either 1.0 or 2.2; see: "::TEXTURE_GAMMA"
+
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO; used in LLDrawPoolAlpha::beginRenderPass()
+uniform int no_atmo;
 
 vec3 fullbrightAtmosTransport(vec3 light);
 vec3 fullbrightScaleSoftClip(vec3 light);
@@ -50,9 +53,17 @@ void fullbright_lighting()
 	color.rgb *= vertex_color.rgb;
 
 	color.rgb = pow(color.rgb, vec3(texture_gamma));
-	color.rgb = fullbrightAtmosTransport(color.rgb);
-	
-	color.rgb = fullbrightScaleSoftClip(color.rgb);
+
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 0)
+	{
+		color.rgb = fullbrightAtmosTransport(color.rgb);
+		color.rgb = fullbrightScaleSoftClip(color.rgb);
+	}
+
+	//*TODO: Are we missing an inverse pow() here?
+	// class1\lighting\lightFullbrightF.glsl has:
+    //     color.rgb = pow(color.rgb, vec3(1.0/texture_gamma));
 
 	frag_color = color;
 }
diff --git a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightF.glsl b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightF.glsl
index b967709c57..5fcdf3107c 100644
--- a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightF.glsl
@@ -34,6 +34,9 @@ VARYING vec2 vary_texcoord0;
 
 uniform float texture_gamma;
 
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO;
+uniform int no_atmo;
+
 vec3 fullbrightAtmosTransport(vec3 light);
 vec3 fullbrightScaleSoftClip(vec3 light);
 
@@ -43,9 +46,12 @@ void fullbright_lighting()
 	
 	color.rgb = pow(color.rgb, vec3(texture_gamma));
 
-	color.rgb = fullbrightAtmosTransport(color.rgb);
-	
-	color.rgb = fullbrightScaleSoftClip(color.rgb);
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 0)
+	{
+		color.rgb = fullbrightAtmosTransport(color.rgb);
+		color.rgb = fullbrightScaleSoftClip(color.rgb);
+	}
 
 	color.rgb = pow(color.rgb, vec3(1.0/texture_gamma));
 
diff --git a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightShinyF.glsl b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightShinyF.glsl
index 567811cd75..6f7e777d23 100644
--- a/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightShinyF.glsl
+++ b/indra/newview/app_settings/shaders/class1/lighting/lightFullbrightShinyF.glsl
@@ -35,20 +35,37 @@ VARYING vec3 vary_texcoord1;
 
 uniform samplerCube environmentMap;
 
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO; used in LLDrawPoolAlpha::beginRenderPass()
+uniform int no_atmo;
+
 vec3 fullbrightShinyAtmosTransport(vec3 light);
 vec3 fullbrightScaleSoftClip(vec3 light);
 
+// See:
+//   class1\deferred\fullbrightShinyF.glsl
+//   class1\lighting\lightFullbrightShinyF.glsl
 void fullbright_shiny_lighting()
 {
 	vec4 color = diffuseLookup(vary_texcoord0.xy);
 	color.rgb *= vertex_color.rgb;
-	
-	vec3 envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;	
-	color.rgb = mix(color.rgb, envColor.rgb, vertex_color.a*0.75); // MAGIC NUMBER SL-12574; ALM: Off, Quality > Low
 
-	color.rgb = fullbrightShinyAtmosTransport(color.rgb);
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 0)
+	{
+		vec3 envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;
+		color.rgb = mix(color.rgb, envColor.rgb, vertex_color.a*0.75); // MAGIC NUMBER SL-12574; ALM: Off, Quality > Low
 
-	color.rgb = fullbrightScaleSoftClip(color.rgb);
+		color.rgb = fullbrightShinyAtmosTransport(color.rgb);
+		color.rgb = fullbrightScaleSoftClip(color.rgb);
+	}
+/*
+	// NOTE: HUD objects will be full bright. Uncomment if you want "some" environment lighting effecting these HUD objects.
+	else
+	{
+		vec3 envColor = textureCube(environmentMap, vary_texcoord1.xyz).rgb;
+		color.rgb = mix(color.rgb, envColor.rgb, vertex_color.a*0.75); // MAGIC NUMBER SL-12574; ALM: Off, Quality > Low
+	}
+*/
 
 	color.a = 1.0;
 
diff --git a/indra/newview/app_settings/shaders/class1/objects/simpleV.glsl b/indra/newview/app_settings/shaders/class1/objects/simpleV.glsl
index a59bd9c0a6..9ef7704b70 100644
--- a/indra/newview/app_settings/shaders/class1/objects/simpleV.glsl
+++ b/indra/newview/app_settings/shaders/class1/objects/simpleV.glsl
@@ -1,4 +1,4 @@
-/** 
+/**
  * @file simpleV.glsl
  *
  * $LicenseInfo:firstyear=2007&license=viewerlgpl$
@@ -28,6 +28,9 @@ uniform mat4 texture_matrix0;
 uniform mat4 modelview_matrix;
 uniform mat4 modelview_projection_matrix;
 
+// render_hud_attachments() -> HUD objects set LLShaderMgr::NO_ATMO; used in LLDrawPoolAlpha::beginRenderPass()
+uniform int no_atmo;
+
 ATTRIBUTE vec3 position;
 void passTextureIndex();
 ATTRIBUTE vec2 texcoord0;
@@ -46,19 +49,23 @@ void main()
 {
 	//transform vertex
 	vec4 vert = vec4(position.xyz,1.0);
-	passTextureIndex();
-	vec4 pos = (modelview_matrix * vert);
 	gl_Position = modelview_projection_matrix*vec4(position.xyz, 1.0);
+
+	passTextureIndex();
 	vary_texcoord0 = (texture_matrix0 * vec4(texcoord0, 0, 1)).xy;
-	
-	
-	
-	vec3 norm = normalize(normal_matrix * normal);
 
-	calcAtmospherics(pos.xyz);
+	// SL-9632 HUDs are affected by Atmosphere
+	if (no_atmo == 1)
+	{
+		vertex_color = diffuse_color;
+	}
+	else
+	{
+		vec4 pos = (modelview_matrix * vert);
+		vec3 norm = normalize(normal_matrix * normal);
 
-	vec4 color = calcLighting(pos.xyz, norm, diffuse_color);
-	vertex_color = color;
+		calcAtmospherics(pos.xyz);
 
-	
+		vertex_color = calcLighting(pos.xyz, norm, diffuse_color);
+	}
 }
diff --git a/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl
index dcb02bd1c1..ea2690ba09 100644
--- a/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl
@@ -1,154 +1,134 @@
-/** 
+/**
  * @file class1\windlight\atmosphericsFuncs.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2019, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 uniform float cloud_shadow;
 uniform float density_multiplier;
 uniform float distance_multiplier;
 uniform float max_y;
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float scene_light_strength;
-uniform mat3 ssao_effect_mat;
-uniform int no_atmo;
+uniform mat3  ssao_effect_mat;
+uniform int   no_atmo;
 uniform float sun_moon_glow_factor;
 
-float getAmbientClamp()
+float getAmbientClamp() { return 1.0f; }
+
+void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive,
+                         out vec3 atten, bool use_ao)
 {
-    return 1.0f;
-}
+    vec3 rel_pos = inPositionEye;
 
+    //(TERRAIN) limit altitude
+    if (abs(rel_pos.y) > max_y) rel_pos *= (max_y / rel_pos.y);
 
-void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao) {
+    vec3  rel_pos_norm = normalize(rel_pos);
+    float rel_pos_len  = length(rel_pos);
+    vec4  sunlight     = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
 
-    vec3 P = inPositionEye;
-   
-    //(TERRAIN) limit altitude
-    if (P.y > max_y) P *= (max_y / P.y);
-    if (P.y < -max_y) P *= (-max_y / P.y); 
+    // sunlight attenuation effect (hue and brightness) due to atmosphere
+    // this is used later for sunlight modulation at various altitudes
+    vec4 light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
+    // I had thought blue_density and haze_density should have equal weighting,
+    // but attenuation due to haze_density tends to seem too strong
 
-    vec3 tmpLightnorm = lightnorm.xyz;
+    vec4 combined_haze = blue_density + vec4(haze_density);
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = vec4(haze_density) / combined_haze;
 
-    vec3 Pn = normalize(P);
-    float Plen = length(P);
+    //(TERRAIN) compute sunlight from lightnorm y component. Factor is roughly cosecant(sun elevation) (for short rays like terrain)
+    float above_horizon_factor = 1.0 / max(1e-6, lightnorm.y);
+    sunlight *= exp(-light_atten * above_horizon_factor);  // for sun [horizon..overhead] this maps to an exp curve [0..1]
+
+    // main atmospheric scattering line integral
+    float density_dist = rel_pos_len * density_multiplier;
 
-    vec4 temp1 = vec4(0);
-    vec3 temp2 = vec3(0);
-    vec4 blue_weight;
-    vec4 haze_weight;
-    vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-    vec4 light_atten;
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist*distance_multiplier in a variable because the ati
+    // compiler gets confused.
+    combined_haze = exp(-combined_haze * density_dist * distance_multiplier);
 
-    float dens_mul = density_multiplier;
-    float dist_mul = distance_multiplier;
+    // final atmosphere attenuation factor
+    atten = combined_haze.rgb;
 
-    //sunlight attenuation effect (hue and brightness) due to atmosphere
-    //this is used later for sunlight modulation at various altitudes
-    light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
-        //I had thought blue_density and haze_density should have equal weighting,
-        //but attenuation due to haze_density tends to seem too strong
+    // compute haze glow
+    float haze_glow = dot(rel_pos_norm, lightnorm.xyz);
 
-    temp1 = blue_density + vec4(haze_density);
-    blue_weight = blue_density / temp1;
-    haze_weight = vec4(haze_density) / temp1;
+    // dampen sun additive contrib when not facing it...
+    // SL-13539: This "if" clause causes an "additive" white artifact at roughly 77 degreees.
+    //    if (length(light_dir) > 0.01)
+    haze_glow *= max(0.0f, dot(light_dir, rel_pos_norm));
 
-    //(TERRAIN) compute sunlight from lightnorm only (for short rays like terrain)
-    temp2.y = max(0.0, tmpLightnorm.y);
-    if (abs(temp2.y) > 0.000001f)
-    {
-        temp2.y = 1. / abs(temp2.y);
-    }
-    temp2.y = max(0.0000001f, temp2.y);
-    sunlight *= exp(-light_atten * temp2.y);
+    haze_glow = 1. - haze_glow;
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);  // set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
 
-    // main atmospheric scattering line integral
-    temp2.z = Plen * dens_mul;
+    // add "minimum anti-solar illumination"
+    haze_glow += .25;
 
-    // Transparency (-> temp1)
-    // ATI Bugfix -- can't store temp1*temp2.z*dist_mul in a variable because the ati
-    // compiler gets confused.
-    temp1 = exp(-temp1 * temp2.z * dist_mul);
+    haze_glow *= sun_moon_glow_factor;
 
-    //final atmosphere attenuation factor
-    atten = temp1.rgb;
-    
-    //compute haze glow
-    //(can use temp2.x as temp because we haven't used it yet)
-    temp2.x = dot(Pn, tmpLightnorm.xyz);
+    vec4 amb_color = ambient_color;
 
-    // dampen sun additive contrib when not facing it...
-    if (length(light_dir) > 0.01)
-    {
-        temp2.x *= max(0.0f, dot(light_dir, Pn));
-    }
-    temp2.x = 1. - temp2.x;
-        //temp2.x is 0 at the sun and increases away from sun
-    temp2.x = max(temp2.x, .001);    //was glow.y
-        //set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-    temp2.x *= glow.x;
-        //higher glow.x gives dimmer glow (because next step is 1 / "angle")
-    temp2.x = pow(temp2.x, glow.z);
-        //glow.z should be negative, so we're doing a sort of (1 / "angle") function
-
-    //add "minimum anti-solar illumination"
-    temp2.x += .25;
-
-    temp2.x *= sun_moon_glow_factor;
- 
-    vec4 amb_color = ambient_color; 
-    
-    //increase ambient when there are more clouds
+    // increase ambient when there are more clouds
     vec4 tmpAmbient = amb_color + (vec4(1.) - amb_color) * cloud_shadow * 0.5;
-    
+
     /*  decrease value and saturation (that in HSV, not HSL) for occluded areas
      * // for HSV color/geometry used here, see http://gimp-savvy.com/BOOK/index.html?node52.html
      * // The following line of code performs the equivalent of:
      * float ambAlpha = tmpAmbient.a;
      * float ambValue = dot(vec3(tmpAmbient), vec3(0.577)); // projection onto <1/rt(3), 1/rt(3), 1/rt(3)>, the neutral white-black axis
      * vec3 ambHueSat = vec3(tmpAmbient) - vec3(ambValue);
-     * tmpAmbient = vec4(RenderSSAOEffect.valueFactor * vec3(ambValue) + RenderSSAOEffect.saturationFactor *(1.0 - ambFactor) * ambHueSat, ambAlpha);
+     * tmpAmbient = vec4(RenderSSAOEffect.valueFactor * vec3(ambValue) + RenderSSAOEffect.saturationFactor *(1.0 - ambFactor) * ambHueSat,
+     * ambAlpha);
      */
     if (use_ao)
     {
         tmpAmbient = vec4(mix(ssao_effect_mat * tmpAmbient.rgb, tmpAmbient.rgb, ambFactor), tmpAmbient.a);
     }
 
-    //haze color
-        additive =
-        vec3(blue_horizon * blue_weight * (sunlight*(1.-cloud_shadow) + tmpAmbient)
-      + (haze_horizon * haze_weight) * (sunlight*(1.-cloud_shadow) * temp2.x
-          + tmpAmbient));
+    // Similar/Shared Algorithms:
+    //     indra\llinventory\llsettingssky.cpp                                        -- LLSettingsSky::calculateLightSettings()
+    //     indra\newview\app_settings\shaders\class1\windlight\atmosphericsFuncs.glsl -- calcAtmosphericVars()
+    // haze color
+    vec3 cs = sunlight.rgb * (1. - cloud_shadow);
+    additive = (blue_horizon.rgb * blue_weight.rgb) * (cs + tmpAmbient.rgb) + (haze_horizon * haze_weight.rgb) * (cs * haze_glow + tmpAmbient.rgb);
 
-    //brightness of surface both sunlight and ambient
+    // brightness of surface both sunlight and ambient
     sunlit = sunlight.rgb * 0.5;
     amblit = tmpAmbient.rgb * .25;
-    additive *= vec3(1.0 - temp1);
+    additive *= vec3(1.0 - combined_haze);
 }
diff --git a/indra/newview/app_settings/shaders/class1/windlight/moonF.glsl b/indra/newview/app_settings/shaders/class1/windlight/moonF.glsl
index 24f3992e32..2425a2ad04 100644
--- a/indra/newview/app_settings/shaders/class1/windlight/moonF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/moonF.glsl
@@ -3,7 +3,7 @@
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2005, Linden Research, Inc.
+ * Copyright (C) 2005, 2020 Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -36,28 +36,30 @@ out vec4 frag_color;
 uniform vec4 color;
 uniform vec4 sunlight_color;
 uniform vec4 moonlight_color;
-uniform vec3 lumWeights;
+uniform vec3 moon_dir;
 uniform float moon_brightness;
-uniform float minLuminance;
 uniform sampler2D diffuseMap;
-uniform sampler2D altDiffuseMap;
-uniform float blend_factor; // interp factor between moon A/B
+
 VARYING vec2 vary_texcoord0;
 
+vec3 scaleSoftClip(vec3 light);
+
 void main() 
 {
-    vec4 moonA = texture2D(diffuseMap, vary_texcoord0.xy);
-    vec4 moonB = texture2D(altDiffuseMap, vary_texcoord0.xy);
-    vec4 c     = mix(moonA, moonB, blend_factor);
+    // Restore Pre-EEP alpha fade moon near horizon
+    float fade = 1.0;
+    if( moon_dir.z > 0 )
+        fade = clamp( moon_dir.z*moon_dir.z*4.0, 0.0, 1.0 );
+
+    vec4 c     = texture2D(diffuseMap, vary_texcoord0.xy);
+//       c.rgb = pow(c.rgb, vec3(0.7f)); // can't use "srgb_to_linear(color.rgb)" as that is a deferred only function
+         c.rgb *= moonlight_color.rgb;
+         c.rgb *= moon_brightness;
 
-    // mix factor which blends when sunlight is brighter
-    // and shows true moon color at night
-    vec3 luma_weights = vec3(0.3, 0.5, 0.3);
-    float mix = 1.0f - dot(normalize(sunlight_color.rgb), luma_weights);
+         c.rgb *= fade;
+         c.a   *= fade;
 
-    vec3 exp = vec3(1.0 - mix * moon_brightness) * 2.0 - 1.0;
-    c.rgb = pow(c.rgb, exp);
-    //c.rgb *= moonlight_color.rgb;
+         c.rgb  = scaleSoftClip(c.rgb);
 
     frag_color = vec4(c.rgb, c.a);
 }
diff --git a/indra/newview/app_settings/shaders/class1/windlight/moonV.glsl b/indra/newview/app_settings/shaders/class1/windlight/moonV.glsl
index 8cd4b2ef47..2fceb5f743 100644
--- a/indra/newview/app_settings/shaders/class1/windlight/moonV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/moonV.glsl
@@ -3,7 +3,7 @@
  *
   * $LicenseInfo:firstyear=2007&license=viewerlgpl$
  * Second Life Viewer Source Code
- * Copyright (C) 2007, Linden Research, Inc.
+ * Copyright (C) 2007, 2020 Linden Research, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -30,20 +30,15 @@ uniform mat4 modelview_projection_matrix;
 ATTRIBUTE vec3 position;
 ATTRIBUTE vec2 texcoord0;
 
-void calcAtmospherics(vec3 inPositionEye);
-
 VARYING vec2 vary_texcoord0;
 
 void main()
 {
     //transform vertex
-    vec3 offset = vec3(0, 0, 50);
-    vec4 vert = vec4(position.xyz - offset, 1.0);
+    vec4 vert = vec4(position.xyz, 1.0);
     vec4 pos = (modelview_matrix * vert);
 
     gl_Position = modelview_projection_matrix*vert;
     
     vary_texcoord0 = (texture_matrix0 * vec4(texcoord0,0,1)).xy;
-    
-    calcAtmospherics(pos.xyz);
 }
diff --git a/indra/newview/app_settings/shaders/class2/deferred/skyF.glsl b/indra/newview/app_settings/shaders/class2/deferred/skyF.glsl
index 1dce85a83b..1485c515a4 100644
--- a/indra/newview/app_settings/shaders/class2/deferred/skyF.glsl
+++ b/indra/newview/app_settings/shaders/class2/deferred/skyF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class2/deferred/skyF.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2005, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -32,13 +32,13 @@ uniform mat4 modelview_projection_matrix;
 // Inputs
 uniform vec3 camPosLocal;
 
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 
@@ -47,7 +47,7 @@ uniform float density_multiplier;
 uniform float distance_multiplier;
 uniform float max_y;
 
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float sun_moon_glow_factor;
 
 uniform vec4 cloud_color;
@@ -73,16 +73,16 @@ uniform float ice_level;
 
 vec3 rainbow(float d)
 {
-   d = clamp(d, -1.0, 0.0);
-   float rad = (droplet_radius - 5.0f) / 1024.0f;
-   return pow(texture2D(rainbow_map, vec2(rad, d)).rgb, vec3(1.8)) * moisture_level;
+    d         = clamp(d, -1.0, 0.0);
+    float rad = (droplet_radius - 5.0f) / 1024.0f;
+    return pow(texture2D(rainbow_map, vec2(rad, d)).rgb, vec3(1.8)) * moisture_level;
 }
 
 vec3 halo22(float d)
 {
-   d = clamp(d, 0.1, 1.0);
-   float v = sqrt(clamp(1 - (d * d), 0, 1));
-   return texture2D(halo_map, vec2(0, v)).rgb * ice_level;
+    d       = clamp(d, 0.1, 1.0);
+    float v = sqrt(clamp(1 - (d * d), 0, 1));
+    return texture2D(halo_map, vec2(0, v)).rgb * ice_level;
 }
 
 /// Soft clips the light with a gamma correction
@@ -90,115 +90,96 @@ vec3 scaleSoftClip(vec3 light);
 
 void main()
 {
-
     // World / view / projection
-    // Get relative position
-    vec3 P = pos.xyz - camPosLocal.xyz + vec3(0,50,0);
+    // Get relative position (offset why?)
+    vec3 rel_pos = pos.xyz - camPosLocal.xyz + vec3(0, 50, 0);
 
-    // Set altitude
-    if (P.y > 0.)
+    // Adj position vector to clamp altitude
+    if (rel_pos.y > 0.)
     {
-        P *= (max_y / P.y);
+        rel_pos *= (max_y / rel_pos.y);
     }
-    else
+    if (rel_pos.y < 0.)
     {
-        P *= (-32000. / P.y);
+        rel_pos *= (-32000. / rel_pos.y);
     }
 
-    // Can normalize then
-    vec3 Pn = normalize(P);
-    float  Plen = length(P);
+    // Normalized
+    vec3  rel_pos_norm = normalize(rel_pos);
+    float rel_pos_len  = length(rel_pos);
 
     // Initialize temp variables
-    vec4 temp1 = vec4(0.);
-    vec4 temp2 = vec4(0.);
-    vec4 blue_weight;
-    vec4 haze_weight;
     vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-    vec4 light_atten;
-
-    float dens_mul = density_multiplier;
 
     // Sunlight attenuation effect (hue and brightness) due to atmosphere
     // this is used later for sunlight modulation at various altitudes
-    light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
+    vec4 light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
 
     // Calculate relative weights
-    temp1 = abs(blue_density) + vec4(abs(haze_density));
-    blue_weight = blue_density / temp1;
-    haze_weight = haze_density / temp1;
+    vec4 combined_haze = abs(blue_density) + vec4(abs(haze_density));
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = haze_density / combined_haze;
 
-    // Compute sunlight from P & lightnorm (for long rays like sky)
-    temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
-    temp2.y = 1. / temp2.y;
-    sunlight *= exp( - light_atten * temp2.y);
+    // Compute sunlight from rel_pos & lightnorm (for long rays like sky)
+    float off_axis = 1.0 / max(1e-6, max(0, rel_pos_norm.y) + lightnorm.y);
+    sunlight *= exp(-light_atten * off_axis);
 
     // Distance
-    temp2.z = Plen * dens_mul;
+    float density_dist = rel_pos_len * density_multiplier;
 
-    // Transparency (-> temp1)
-    // ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati
     // compiler gets confused.
-    temp1 = exp(-temp1 * temp2.z);
+    combined_haze = exp(-combined_haze * density_dist);
 
     // Compute haze glow
-    temp2.x = dot(Pn, lightnorm.xyz);
-    temp2.x = 1. - temp2.x;
-        // temp2.x is 0 at the sun and increases away from sun
-    temp2.x = max(temp2.x, .001);   
-        // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-    temp2.x *= glow.x;
-        // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
-    temp2.x = pow(temp2.x, glow.z);
-        // glow.z should be negative, so we're doing a sort of (1 / "angle") function
+    float haze_glow = dot(rel_pos_norm, lightnorm.xyz);
+    haze_glow       = 1. - haze_glow;
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);
+    // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
 
     // Add "minimum anti-solar illumination"
-    temp2.x += .25;
-
-    temp2.x *= sun_moon_glow_factor;
+    // For sun, add to glow.  For moon, remove glow entirely. SL-13768
+    haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (sun_moon_glow_factor * (haze_glow + 0.25));
 
     // Haze color above cloud
-    vec4 color = (    blue_horizon * blue_weight * (sunlight + ambient_color)
-                + (haze_horizon * haze_weight) * (sunlight * temp2.x + ambient_color)
-             ); 
+    vec4 color = blue_horizon * blue_weight * (sunlight + ambient_color) 
+               + haze_horizon * haze_weight * (sunlight * haze_glow + ambient_color);
 
     // Final atmosphere additive
-    color *= (1. - temp1);
+    color *= (1. - combined_haze);
 
     // Increase ambient when there are more clouds
-    vec4 tmpAmbient = ambient_color;
-    tmpAmbient += max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5; 
+    // TODO 9/20: DJH what does this do?  max(0,(1-ambient)) will change the color
+    vec4 ambient = ambient_color + max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5;
 
     // Dim sunlight by cloud shadow percentage
     sunlight *= max(0.0, (1. - cloud_shadow));
 
     // Haze color below cloud
-    vec4 additiveColorBelowCloud = (blue_horizon * blue_weight * (sunlight + tmpAmbient)
-                + (haze_horizon * haze_weight) * (sunlight * temp2.x + tmpAmbient)
-             ); 
+    vec4 add_below_cloud = blue_horizon * blue_weight * (sunlight + ambient) 
+                         + haze_horizon * haze_weight * (sunlight * haze_glow + ambient);
 
-    
-    
     // Attenuate cloud color by atmosphere
-    temp1 = sqrt(temp1);    //less atmos opacity (more transparency) below clouds
+    combined_haze = sqrt(combined_haze);  // less atmos opacity (more transparency) below clouds
 
     // At horizon, blend high altitude sky color towards the darker color below the clouds
-    color += (additiveColorBelowCloud - color) * (1. - sqrt(temp1));
-    
-    float optic_d = dot(Pn, lightnorm.xyz);
-
-    vec3 halo_22 = halo22(optic_d);
+    color += (add_below_cloud - color) * (1. - sqrt(combined_haze));
 
+    float optic_d = dot(rel_pos_norm, lightnorm.xyz);
+    vec3  halo_22 = halo22(optic_d);
     color.rgb += rainbow(optic_d);
-
     color.rgb += halo_22;
-
     color.rgb *= 2.;
     color.rgb = scaleSoftClip(color.rgb);
 
-    /// Gamma correct for WL (soft clip effect).
+    // Gamma correct for WL (soft clip effect).
     frag_data[0] = vec4(color.rgb, 1.0);
-    frag_data[1] = vec4(0.0,0.0,0.0,0.0);
-    frag_data[2] = vec4(0.0,0.0,0.0,1.0); //1.0 in norm.w masks off fog
+    frag_data[1] = vec4(0.0, 0.0, 0.0, 0.0);
+    frag_data[2] = vec4(0.0, 0.0, 0.0, 1.0);  // 1.0 in norm.w masks off fog
 }
-
diff --git a/indra/newview/app_settings/shaders/class2/deferred/softenLightF.glsl b/indra/newview/app_settings/shaders/class2/deferred/softenLightF.glsl
index b0dff0c628..f4db53e0b7 100644
--- a/indra/newview/app_settings/shaders/class2/deferred/softenLightF.glsl
+++ b/indra/newview/app_settings/shaders/class2/deferred/softenLightF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class2/deferred/softenLightF.glsl
  *
  * $LicenseInfo:firstyear=2007&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2007, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -39,7 +39,7 @@ uniform sampler2DRect specularRect;
 uniform sampler2DRect normalMap;
 uniform sampler2DRect lightMap;
 uniform sampler2DRect depthMap;
-uniform samplerCube environmentMap;
+uniform samplerCube   environmentMap;
 uniform sampler2D     lightFunc;
 
 uniform float blur_size;
@@ -50,7 +50,7 @@ uniform mat3 env_mat;
 
 uniform vec3 sun_dir;
 uniform vec3 moon_dir;
-uniform int sun_up_factor;
+uniform int  sun_up_factor;
 VARYING vec2 vary_fragcoord;
 
 uniform mat4 inv_proj;
@@ -61,10 +61,10 @@ vec4 getPositionWithDepth(vec2 pos_screen, float depth);
 
 void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);
 float getAmbientClamp();
-vec3 atmosFragLighting(vec3 l, vec3 additive, vec3 atten);
-vec3 scaleSoftClipFrag(vec3 l);
-vec3 fullbrightAtmosTransportFrag(vec3 light, vec3 additive, vec3 atten);
-vec3 fullbrightScaleSoftClip(vec3 light);
+vec3  atmosFragLighting(vec3 l, vec3 additive, vec3 atten);
+vec3  scaleSoftClipFrag(vec3 l);
+vec3  fullbrightAtmosTransportFrag(vec3 light, vec3 additive, vec3 atten);
+vec3  fullbrightScaleSoftClip(vec3 light);
 
 vec3 linear_to_srgb(vec3 c);
 vec3 srgb_to_linear(vec3 c);
@@ -73,128 +73,85 @@ vec3 srgb_to_linear(vec3 c);
 vec4 applyWaterFogView(vec3 pos, vec4 color);
 #endif
 
-void main() 
+void main()
 {
-    vec2 tc = vary_fragcoord.xy;
-    float depth = texture2DRect(depthMap, tc.xy).r;
-    vec4 pos = getPositionWithDepth(tc, depth);
-    vec4 norm = texture2DRect(normalMap, tc);
+    vec2  tc           = vary_fragcoord.xy;
+    float depth        = texture2DRect(depthMap, tc.xy).r;
+    vec4  pos          = getPositionWithDepth(tc, depth);
+    vec4  norm         = texture2DRect(normalMap, tc);
     float envIntensity = norm.z;
-    norm.xyz = getNorm(tc);
-    
-    vec3 light_dir = (sun_up_factor == 1) ? sun_dir : moon_dir;
-    float da = clamp(dot(norm.xyz, light_dir.xyz), 0.0, 1.0);
-    float light_gamma = 1.0/1.3;
-    da = pow(da, light_gamma);
-    
+    norm.xyz           = getNorm(tc);
+
+    vec3  light_dir   = (sun_up_factor == 1) ? sun_dir : moon_dir;
+    float da          = clamp(dot(norm.xyz, light_dir.xyz), 0.0, 1.0);
+    float light_gamma = 1.0 / 1.3;
+    da                = pow(da, light_gamma);
+
     vec4 diffuse = texture2DRect(diffuseRect, tc);
-    
-    vec4 spec = texture2DRect(specularRect, vary_fragcoord.xy);
+    vec4 spec    = texture2DRect(specularRect, vary_fragcoord.xy);
 
     vec2 scol_ambocc = texture2DRect(lightMap, vary_fragcoord.xy).rg;
-    scol_ambocc = pow(scol_ambocc, vec2(light_gamma));
+    scol_ambocc      = pow(scol_ambocc, vec2(light_gamma));
+    float scol       = max(scol_ambocc.r, diffuse.a);
+    float ambocc     = scol_ambocc.g;
 
-    float scol = max(scol_ambocc.r, diffuse.a); 
+    vec3  color = vec3(0);
+    float bloom = 0.0;
 
-    float ambocc = scol_ambocc.g;
+    vec3 sunlit;
+    vec3 amblit;
+    vec3 additive;
+    vec3 atten;
+    calcAtmosphericVars(pos.xyz, light_dir, ambocc, sunlit, amblit, additive, atten, true);
 
-    vec3 color = vec3(0);
-    float bloom = 0.0;
+    color.rgb = amblit;
+
+    float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);
+    ambient *= 0.5;
+    ambient *= ambient;
+    ambient = (1.0 - ambient);
+    color.rgb *= ambient;
+
+    vec3 sun_contrib = min(da, scol) * sunlit;
+    color.rgb += sun_contrib;
+    color.rgb *= diffuse.rgb;
+
+    vec3 refnormpersp = normalize(reflect(pos.xyz, norm.xyz));
+
+    if (spec.a > 0.0)  // specular reflection
     {
-        vec3 sunlit;
-        vec3 amblit;
-        vec3 additive;
-        vec3 atten;
-    
-        calcAtmosphericVars(pos.xyz, light_dir, ambocc, sunlit, amblit, additive, atten, true);
-
-        color.rgb = amblit;
-
-        float ambient = min(abs(dot(norm.xyz, sun_dir.xyz)), 1.0);
-        ambient *= 0.5;
-        ambient *= ambient;
-        ambient = (1.0 - ambient);
-
-        color.rgb *= ambient;
-
-        vec3 sun_contrib = min(da, scol) * sunlit;
-
-        color.rgb += sun_contrib;
-
-        color.rgb *= diffuse.rgb;
-
-        vec3 refnormpersp = normalize(reflect(pos.xyz, norm.xyz));
-
-        if (spec.a > 0.0) // specular reflection
-        {
-
-#if 1 //EEP
-            vec3 npos = -normalize(pos.xyz);
-
-            //vec3 ref = dot(pos+lv, norm);
-            vec3 h = normalize(light_dir.xyz+npos);
-            float nh = dot(norm.xyz, h);
-            float nv = dot(norm.xyz, npos);
-            float vh = dot(npos, h);
-            float sa = nh;
-            float fres = pow(1 - dot(h, npos), 5)*0.4+0.5;
-
-            float gtdenom = 2 * nh;
-            float gt = max(0, min(gtdenom * nv / vh, gtdenom * da / vh));
-            
-            if (nh > 0.0)
-            {
-                float scontrib = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt/(nh*da);
-                vec3 sp = sun_contrib*scontrib / 6.0;
-                sp = clamp(sp, vec3(0), vec3(1));
-                bloom += dot(sp, sp) / 4.0;
-                color += sp * spec.rgb;
-            }
-#else //PRODUCTION
-            float sa = dot(refnormpersp, light_dir.xyz);
-            vec3 dumbshiny = sunlit*(texture2D(lightFunc, vec2(sa, spec.a)).r);
-            
-            // add the two types of shiny together
-            vec3 spec_contrib = dumbshiny * spec.rgb;
-            bloom = dot(spec_contrib, spec_contrib) / 6;
-            color.rgb += spec_contrib;
-#endif
+        float sa        = dot(refnormpersp, light_dir.xyz);
+        vec3  dumbshiny = sunlit * scol * (texture2D(lightFunc, vec2(sa, spec.a)).r);
+
+        // add the two types of shiny together
+        vec3 spec_contrib = dumbshiny * spec.rgb;
+        bloom             = dot(spec_contrib, spec_contrib) / 6;
+        color.rgb += spec_contrib;
+    }
+
+    color.rgb = mix(color.rgb, diffuse.rgb, diffuse.a);
 
-        }
-       
-       color.rgb = mix(color.rgb, diffuse.rgb, diffuse.a);
-
-        if (envIntensity > 0.0)
-        { //add environmentmap
-            vec3 env_vec = env_mat * refnormpersp;
-            vec3 reflected_color = textureCube(environmentMap, env_vec).rgb;
-            color = mix(color.rgb, reflected_color, envIntensity);
-        }
-       
-        if (norm.w < 0.5)
-        {
-            color = mix(atmosFragLighting(color, additive, atten), fullbrightAtmosTransportFrag(color, additive, atten), diffuse.a);
-            color = mix(scaleSoftClipFrag(color), fullbrightScaleSoftClip(color), diffuse.a);
-        }
-
-        #ifdef WATER_FOG
-            vec4 fogged = applyWaterFogView(pos.xyz,vec4(color, bloom));
-            color = fogged.rgb;
-            bloom = fogged.a;
-        #endif
+    if (envIntensity > 0.0)
+    {  // add environmentmap
+        vec3 env_vec         = env_mat * refnormpersp;
+        vec3 reflected_color = textureCube(environmentMap, env_vec).rgb;
+        color                = mix(color.rgb, reflected_color, envIntensity);
+    }
 
+    if (norm.w < 0.5)
+    {
+        color = mix(atmosFragLighting(color, additive, atten), fullbrightAtmosTransportFrag(color, additive, atten), diffuse.a);
+        color = mix(scaleSoftClipFrag(color), fullbrightScaleSoftClip(color), diffuse.a);
     }
 
-// linear debuggables
-//color.rgb = vec3(final_da);
-//color.rgb = vec3(ambient);
-//color.rgb = vec3(scol);
-//color.rgb = diffuse_srgb.rgb;
+#ifdef WATER_FOG
+    vec4 fogged = applyWaterFogView(pos.xyz, vec4(color, bloom));
+    color       = fogged.rgb;
+    bloom       = fogged.a;
+#endif
 
     // convert to linear as fullscreen lights need to sum in linear colorspace
     // and will be gamma (re)corrected downstream...
-    
     frag_color.rgb = srgb_to_linear(color.rgb);
-    frag_color.a = bloom;
+    frag_color.a   = bloom;
 }
-
diff --git a/indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl b/indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl
index 2c1475d547..1f881eb44b 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl
+++ b/indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class2\wl\cloudsV.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2005, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -33,25 +33,26 @@ ATTRIBUTE vec2 texcoord0;
 ///////////////////////////////////////////////////////////////////////////////
 
 // Output parameters
-VARYING vec4 vary_CloudColorSun;
-VARYING vec4 vary_CloudColorAmbient;
+VARYING vec4  vary_CloudColorSun;
+VARYING vec4  vary_CloudColorAmbient;
 VARYING float vary_CloudDensity;
-VARYING vec2 vary_texcoord0;
-VARYING vec2 vary_texcoord1;
-VARYING vec2 vary_texcoord2;
-VARYING vec2 vary_texcoord3;
+
+VARYING vec2  vary_texcoord0;
+VARYING vec2  vary_texcoord1;
+VARYING vec2  vary_texcoord2;
+VARYING vec2  vary_texcoord3;
 VARYING float altitude_blend_factor;
 
 // Inputs
 uniform vec3 camPosLocal;
 
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 
@@ -59,141 +60,133 @@ uniform float cloud_shadow;
 uniform float density_multiplier;
 uniform float max_y;
 
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float sun_moon_glow_factor;
 
 uniform vec4 cloud_color;
 
 uniform float cloud_scale;
 
+// NOTE: Keep these in sync!
+//       indra\newview\app_settings\shaders\class1\deferred\skyV.glsl
+//       indra\newview\app_settings\shaders\class1\deferred\cloudsV.glsl
+//       indra\newview\app-settings\shaders\class2\windlight\cloudsV.glsl
+//       indra\newview\lllegacyatmospherics.cpp
+//       indra\newview\llsettingsvo.cpp
 void main()
 {
+    // World / view / projection
+    gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0);
+
+    // Texture coords
+    // SL-13084 EEP added support for custom cloud textures -- flip them horizontally to match the preview of Clouds > Cloud Scroll
+    vary_texcoord0 = vec2(-texcoord0.x, texcoord0.y);  // See: LLSettingsVOSky::applySpecial
 
-	// World / view / projection
-	gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0);
+    vary_texcoord0.xy -= 0.5;
+    vary_texcoord0.xy /= cloud_scale;
+    vary_texcoord0.xy += 0.5;
 
-	vary_texcoord0 = texcoord0;
+    vary_texcoord1 = vary_texcoord0;
+    vary_texcoord1.x += lightnorm.x * 0.0125;
+    vary_texcoord1.y += lightnorm.z * 0.0125;
 
-	// Get relative position
-	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
+    vary_texcoord2 = vary_texcoord0 * 16.;
+    vary_texcoord3 = vary_texcoord1 * 16.;
+
+    // Get relative position
+    vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0);
 
     // fade clouds beyond a certain point so the bottom of the sky dome doesn't look silly at high altitude
-    altitude_blend_factor = clamp((P.y + 512.0) / max_y, 0.0, 1.0);
-
-	// Set altitude
-	if (P.y > 0.)
-	{
-		P *= (max_y / P.y);
-	}
-	else
-	{
-		P *= (-32000. / P.y);
-	}
-
-	// Can normalize then
-	vec3 Pn = normalize(P);
-	float  Plen = length(P);
-
-	// Initialize temp variables
-	vec4 temp1 = vec4(0.);
-	vec4 temp2 = vec4(0.);
-	vec4 blue_weight;
-	vec4 haze_weight;
-	//vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-	vec4 sunlight = sunlight_color;
-	vec4 light_atten;
-
-    float dens_mul = density_multiplier;
-
-	// Sunlight attenuation effect (hue and brightness) due to atmosphere
-	// this is used later for sunlight modulation at various altitudes
-	light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
-
-	// Calculate relative weights
-	temp1 = abs(blue_density) + vec4(abs(haze_density));
-	blue_weight = blue_density / temp1;
-	haze_weight = haze_density / temp1;
-
-	// Compute sunlight from P & lightnorm (for long rays like sky)
-	temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
-	temp2.y = 1. / temp2.y;
-	sunlight *= exp( - light_atten * temp2.y);
-
-	// Distance
-	temp2.z = Plen * dens_mul;
-
-	// Transparency (-> temp1)
-	// ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
-	// compiler gets confused.
-	temp1 = exp(-temp1 * temp2.z);
-
-
-	// Compute haze glow
-	temp2.x = dot(Pn, lightnorm.xyz);
-	temp2.x = 1. - temp2.x;
-		// temp2.x is 0 at the sun and increases away from sun
-	temp2.x = max(temp2.x, .001);	
-		// Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-	temp2.x *= glow.x;
-		// Higher glow.x gives dimmer glow (because next step is 1 / "angle")
-	temp2.x = pow(temp2.x, glow.z);
-		// glow.z should be negative, so we're doing a sort of (1 / "angle") function
-
-    temp2.x *= sun_moon_glow_factor;
-
-	// Add "minimum anti-solar illumination"
-	temp2.x += .25;
-
-	// Increase ambient when there are more clouds
-	vec4 tmpAmbient = ambient_color;
-	tmpAmbient += (1. - tmpAmbient) * cloud_shadow * 0.5; 
-
-	// Dim sunlight by cloud shadow percentage
-	sunlight *= (1. - cloud_shadow);
-
-	// Haze color below cloud
-	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
-				+ (haze_horizon * haze_weight) * (sunlight * temp2.x + tmpAmbient)
-			 );	
-
-	// CLOUDS
-	temp2.y = max(0., lightnorm.y * 2.);
-	temp2.y = 1. / temp2.y;
-	sunlight *= exp( - light_atten * temp2.y);
-
-	// Cloud color out
-	vary_CloudColorSun = (sunlight * temp2.x) * cloud_color;
-	vary_CloudColorAmbient = tmpAmbient * cloud_color;
-	
-	// Attenuate cloud color by atmosphere
-	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
-	vary_CloudColorSun *= temp1;
-	vary_CloudColorAmbient *= temp1;
-	vec4 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - temp1);
-
-	// Make a nice cloud density based on the cloud_shadow value that was passed in.
-	vary_CloudDensity = 2. * (cloud_shadow - 0.25);
-
-
-	// Texture coords
-	vary_texcoord0 = texcoord0;
-	vary_texcoord0.xy -= 0.5;
-	vary_texcoord0.xy /= cloud_scale;
-	vary_texcoord0.xy += 0.5;
-
-	vary_texcoord1 = vary_texcoord0;
-	vary_texcoord1.x += lightnorm.x * 0.0125;
-	vary_texcoord1.y += lightnorm.z * 0.0125;
-
-	vary_texcoord2 = vary_texcoord0 * 16.;
-	vary_texcoord3 = vary_texcoord1 * 16.;
-
-	// Combine these to minimize register use
-	vary_CloudColorAmbient += oHazeColorBelowCloud;
-
-	// needs this to compile on mac
-	//vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
-
-	// END CLOUDS
+    altitude_blend_factor = clamp((rel_pos.y + 512.0) / max_y, 0.0, 1.0);
+
+    // Adj position vector to clamp altitude
+    if (rel_pos.y > 0.)
+    {
+        rel_pos *= (max_y / rel_pos.y);
+    }
+    if (rel_pos.y < 0.)
+    {
+        rel_pos *= (-32000. / rel_pos.y);
+    }
+
+    // Can normalize then
+    vec3  rel_pos_norm = normalize(rel_pos);
+    float rel_pos_len  = length(rel_pos);
+
+    // Initialize temp variables
+    vec4 sunlight = sunlight_color;
+    vec4 light_atten;
+
+    // Sunlight attenuation effect (hue and brightness) due to atmosphere
+    // this is used later for sunlight modulation at various altitudes
+    light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
+
+    // Calculate relative weights
+    vec4 combined_haze = abs(blue_density) + vec4(abs(haze_density));
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = haze_density / combined_haze;
+
+    // Compute sunlight from rel_pos & lightnorm (for long rays like sky)
+    float off_axis = 1.0 / max(1e-6, max(0., rel_pos_norm.y) + lightnorm.y);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Distance
+    float density_dist = rel_pos_len * density_multiplier;
+
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati
+    // compiler gets confused.
+    combined_haze = exp(-combined_haze * density_dist);
+
+    // Compute haze glow
+    float haze_glow = 1.0 - dot(rel_pos_norm, lightnorm.xyz);
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);
+    // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
+
+    haze_glow *= sun_moon_glow_factor;
+
+    // Add "minimum anti-solar illumination"
+    // For sun, add to glow.  For moon, remove glow entirely. SL-13768
+    haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (haze_glow + 0.25);
+
+    // Increase ambient when there are more clouds
+    vec4 tmpAmbient = ambient_color;
+    tmpAmbient += (1. - tmpAmbient) * cloud_shadow * 0.5;
+
+    // Dim sunlight by cloud shadow percentage
+    sunlight *= (1. - cloud_shadow);
+
+    // Haze color below cloud
+    vec4 additiveColorBelowCloud =
+        (blue_horizon * blue_weight * (sunlight + tmpAmbient) + (haze_horizon * haze_weight) * (sunlight * haze_glow + tmpAmbient));
+
+    // CLOUDS
+    off_axis = 1.0 / max(1e-6, lightnorm.y * 2.);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Cloud color out
+    vary_CloudColorSun     = (sunlight * haze_glow) * cloud_color;
+    vary_CloudColorAmbient = tmpAmbient * cloud_color;
+
+    // Attenuate cloud color by atmosphere
+    combined_haze = sqrt(combined_haze);  // less atmos opacity (more transparency) below clouds
+    vary_CloudColorSun *= combined_haze;
+    vary_CloudColorAmbient *= combined_haze;
+    vec4 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - combined_haze);
+
+    // Make a nice cloud density based on the cloud_shadow value that was passed in.
+    vary_CloudDensity = 2. * (cloud_shadow - 0.25);
+
+    // Combine these to minimize register use
+    vary_CloudColorAmbient += oHazeColorBelowCloud;
+
+    // needs this to compile on mac
+    // vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
+
+    // END CLOUDS
 }
-
diff --git a/indra/newview/app_settings/shaders/class2/windlight/skyV.glsl b/indra/newview/app_settings/shaders/class2/windlight/skyV.glsl
index 0d141342ce..a0a33b8642 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/skyV.glsl
+++ b/indra/newview/app_settings/shaders/class2/windlight/skyV.glsl
@@ -1,28 +1,28 @@
-/** 
+/**
  * @file class2\wl\skyV.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2005, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
- 
+
 uniform mat4 modelview_projection_matrix;
 
 ATTRIBUTE vec3 position;
@@ -37,13 +37,13 @@ VARYING vec4 vary_HazeColor;
 // Inputs
 uniform vec3 camPosLocal;
 
-uniform vec4 lightnorm;
-uniform vec4 sunlight_color;
-uniform vec4 moonlight_color;
-uniform int sun_up_factor;
-uniform vec4 ambient_color;
-uniform vec4 blue_horizon;
-uniform vec4 blue_density;
+uniform vec4  lightnorm;
+uniform vec4  sunlight_color;
+uniform vec4  moonlight_color;
+uniform int   sun_up_factor;
+uniform vec4  ambient_color;
+uniform vec4  blue_horizon;
+uniform vec4  blue_density;
 uniform float haze_horizon;
 uniform float haze_density;
 
@@ -52,110 +52,98 @@ uniform float density_multiplier;
 uniform float distance_multiplier;
 uniform float max_y;
 
-uniform vec4 glow;
+uniform vec4  glow;
 uniform float sun_moon_glow_factor;
 
 uniform vec4 cloud_color;
 
 void main()
 {
-
-	// World / view / projection
+    // World / view / projection
     vec4 pos = modelview_projection_matrix * vec4(position.xyz, 1.0);
 
-	gl_Position = pos;
-	
-	// Get relative position
-	vec3 P = position.xyz - camPosLocal.xyz + vec3(0,50,0);
-
-	// Set altitude
-	if (P.y > 0.)
-	{
-		P *= (max_y / P.y);
-	}
-	else
-	{
-		P *= (-32000. / P.y);
-	}
-
-	// Can normalize then
-	vec3 Pn = normalize(P);
-
-	float Plen = length(P);
-
-	// Initialize temp variables
-	vec4 temp1 = vec4(0.);
-	vec4 temp2 = vec4(0.);
-	vec4 blue_weight;
-	vec4 haze_weight;
-	vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
-	vec4 light_atten;
-
-    float dens_mul = density_multiplier;
-
-	// Sunlight attenuation effect (hue and brightness) due to atmosphere
-	// this is used later for sunlight modulation at various altitudes
-	light_atten = (blue_density + vec4(haze_density * 0.25)) * (dens_mul * max_y);
-
-	// Calculate relative weights
-	temp1 = abs(blue_density) + vec4(abs(haze_density));
-	blue_weight = blue_density / temp1;
-	haze_weight = haze_density / temp1;
-
-	// Compute sunlight from P & lightnorm (for long rays like sky)
-    temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
-    temp2.y = 1. / temp2.y;
-    sunlight *= exp( - light_atten * temp2.y);
-
-	// Distance
-	temp2.z = Plen * dens_mul;
-
-	// Transparency (-> temp1)
-    // ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
-    // compiler gets confused.
-    temp1 = exp(-temp1 * temp2.z);
+    gl_Position = pos;
+
+    // Get relative position
+    vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0);
+
+    // Adj position vector to clamp altitude
+    if (rel_pos.y > 0.)
+    {
+        rel_pos *= (max_y / rel_pos.y);
+    }
+    if (rel_pos.y < 0.)
+    {
+        rel_pos *= (-32000. / rel_pos.y);
+    }
 
-	// Compute haze glow
-	temp2.x = dot(Pn, lightnorm.xyz);
-	temp2.x = 1. - temp2.x;
-		// temp2.x is 0 at the sun and increases away from sun
-	temp2.x = max(temp2.x, .001);	
-		// Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
-	temp2.x *= glow.x;
-		// Higher glow.x gives dimmer glow (because next step is 1 / "angle")
-	temp2.x = pow(temp2.x, glow.z);
-		// glow.z should be negative, so we're doing a sort of (1 / "angle") function
+    // Can normalize then
+    vec3 rel_pos_norm = normalize(rel_pos);
 
-	// Add "minimum anti-solar illumination"
-	temp2.x += .25;
+    float rel_pos_len = length(rel_pos);
 
-    vec4 color = (    blue_horizon * blue_weight * (sunlight + ambient_color)
-                + (haze_horizon * haze_weight) * (sunlight * temp2.x + ambient_color)
-             );
+    // Initialize temp variables
+    vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color;
+    vec4 light_atten;
 
+    // Sunlight attenuation effect (hue and brightness) due to atmosphere
+    // this is used later for sunlight modulation at various altitudes
+    light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
+
+    // Calculate relative weights
+    vec4 combined_haze = abs(blue_density) + vec4(abs(haze_density));
+    vec4 blue_weight   = blue_density / combined_haze;
+    vec4 haze_weight   = haze_density / combined_haze;
+
+    // Compute sunlight from rel_pos & lightnorm (for long rays like sky)
+    float off_axis = 1.0 / max(1e-6, max(0., rel_pos_norm.y) + lightnorm.y);
+    sunlight *= exp(-light_atten * off_axis);
+
+    // Distance
+    float density_dist = rel_pos_len * density_multiplier;
+
+    // Transparency (-> combined_haze)
+    // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati
+    // compiler gets confused.
+    combined_haze = exp(-combined_haze * density_dist);
+
+    // Compute haze glow
+    float haze_glow = 1.0 - dot(rel_pos_norm, lightnorm.xyz);
+    // haze_glow is 0 at the sun and increases away from sun
+    haze_glow = max(haze_glow, .001);
+    // Set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+    haze_glow *= glow.x;
+    // Higher glow.x gives dimmer glow (because next step is 1 / "angle")
+    haze_glow = pow(haze_glow, glow.z);
+    // glow.z should be negative, so we're doing a sort of (1 / "angle") function
+
+    // Add "minimum anti-solar illumination"
+    // For sun, add to glow.  For moon, remove glow entirely. SL-13768
+    haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (haze_glow + 0.25);
+
+    vec4 color =
+        (blue_horizon * blue_weight * (sunlight + ambient_color) + (haze_horizon * haze_weight) * (sunlight * haze_glow + ambient_color));
 
     // Final atmosphere additive
-    color *= (1. - temp1);
+    color *= (1. - combined_haze);
 
-	// Increase ambient when there are more clouds
-	vec4 tmpAmbient = ambient_color;
-	tmpAmbient += max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5; 
+    // Increase ambient when there are more clouds
+    vec4 tmpAmbient = ambient_color;
+    tmpAmbient += max(vec4(0), (1. - ambient_color)) * cloud_shadow * 0.5;
 
-	// Dim sunlight by cloud shadow percentage
-	sunlight *= max(0.0, (1. - cloud_shadow));
+    // Dim sunlight by cloud shadow percentage
+    sunlight *= max(0.0, (1. - cloud_shadow));
 
-	// Haze color below cloud
-	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
-				+ (haze_horizon * haze_weight) * (sunlight * temp2.x + tmpAmbient)
-			 );	
+    // Haze color below cloud
+    vec4 additiveColorBelowCloud =
+        (blue_horizon * blue_weight * (sunlight + tmpAmbient) + (haze_horizon * haze_weight) * (sunlight * haze_glow + tmpAmbient));
 
-	// Attenuate cloud color by atmosphere
-	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
+    // Attenuate cloud color by atmosphere
+    combined_haze = sqrt(combined_haze);  // less atmos opacity (more transparency) below clouds
 
-	// At horizon, blend high altitude sky color towards the darker color below the clouds
-	color += (additiveColorBelowCloud - color) * (1. - sqrt(temp1));
+    // At horizon, blend high altitude sky color towards the darker color below the clouds
+    color += (additiveColorBelowCloud - color) * (1. - sqrt(combined_haze));
 
     // Haze color above cloud
-	vary_HazeColor = color;	
+    vary_HazeColor = color;
 }
-