Merge branch 'DRTVWR-559' into DRTVWR-583-glossy-ssr

27 files changed, 180 insertions, 208 deletions

diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 533a3361e6..c90c9c543c 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -9116,6 +9116,28 @@
     <key>Value</key>
     <real>500.0</real>
   </map>
+  <key>RenderSSAOIrradianceScale</key>
+  <map>
+    <key>Comment</key>
+    <string>Scaling factor for irradiance input to SSAO</string>
+    <key>Persist</key>
+    <integer>0</integer>
+    <key>Type</key>
+    <string>F32</string>
+    <key>Value</key>
+    <real>0.6</real>
+  </map>
+  <key>RenderSSAOIrradianceMax</key>
+  <map>
+    <key>Comment</key>
+    <string>Max factor for irradiance input to SSAO</string>
+    <key>Persist</key>
+    <integer>0</integer>
+    <key>Type</key>
+    <string>F32</string>
+    <key>Value</key>
+    <real>0.18</real>
+  </map>
   <key>RenderSSAOMaxScale</key>
   <map>
     <key>Comment</key>
@@ -10468,17 +10490,6 @@
     <key>Value</key>
     <integer>1</integer>
   </map>
-  <key>RenderReflectionProbeCount</key>
-  <map>
-    <key>Comment</key>
-    <string>Number of reflection probes (maximum is 256, requires restart)</string>
-    <key>Persist</key>
-    <integer>1</integer>
-    <key>Type</key>
-    <string>S32</string>
-    <key>Value</key>
-    <integer>256</integer>
-  </map>
   <key>RenderReflectionProbeResolution</key>
   <map>
     <key>Comment</key>
@@ -10588,40 +10599,29 @@
     <key>Type</key>
     <string>F32</string>
     <key>Value</key>
-    <real>1.25</real>
-  </map>
-  <key>RenderReflectionProbeMaxLocalLightAmbiance</key>
-  <map>
-    <key>Comment</key>
-    <string>Maximum effective probe ambiance for local lights</string>
-    <key>Persist</key>
-    <integer>0</integer>
-    <key>Type</key>
-    <string>F32</string>
-    <key>Value</key>
-    <real>4.0</real>
+    <real>1.0</real>
   </map>
-  <key>RenderDynamicExposureMin</key>
+  <key>RenderSkyAutoAdjustLegacy</key>
   <map>
     <key>Comment</key>
-    <string>Minimum dynamic exposure amount</string>
+    <string>If true, automatically adjust legacy skies (those without a probe ambiance value) to take advantage of probes and HDR.</string>
     <key>Persist</key>
-    <integer>0</integer>
+    <integer>1</integer>
     <key>Type</key>
-    <string>F32</string>
+    <string>Boolean</string>
     <key>Value</key>
-    <real>0.6</real>
+    <integer>1</integer>
   </map>
-  <key>RenderDynamicExposureMax</key>
+  <key>RenderReflectionProbeMaxLocalLightAmbiance</key>
   <map>
     <key>Comment</key>
-    <string>Maximum dynamic exposure amount</string>
+    <string>Maximum effective probe ambiance for local lights</string>
     <key>Persist</key>
     <integer>0</integer>
     <key>Type</key>
     <string>F32</string>
     <key>Value</key>
-    <real>1.5</real>
+    <real>4.0</real>
   </map>
   <key>RenderDynamicExposureCoefficient</key>
   <map>
diff --git a/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl b/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
index 55e45ce0af..c8eaba6418 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
@@ -387,7 +387,7 @@ vec3 pbrIbl(vec3 diffuseColor,
 {
     // retrieve a scale and bias to F0. See [1], Figure 3
 	vec2 brdf = BRDF(clamp(nv, 0, 1), 1.0-perceptualRough);
-	vec3 diffuseLight = irradiance*1.25;  //magic 1.25 to balance with legacy materials
+	vec3 diffuseLight = irradiance;
 	vec3 specularLight = radiance;
     
 	vec3 diffuse = diffuseLight * diffuseColor;
@@ -563,7 +563,7 @@ vec3 pbrBaseLight(vec3 diffuseColor, vec3 specularColor, float metallic, vec3 v,
     vec3 ibl_spec;
     color += pbrIbl(diffuseColor, specularColor, radiance, irradiance, ao, NdotV, perceptualRoughness, ibl_spec);
     
-    color += pbrPunctual(diffuseColor, specularColor, perceptualRoughness, metallic, norm, v, normalize(light_dir), specContrib) * sunlit * 3.9 * scol; //magic number to balance with legacy materials
+    color += pbrPunctual(diffuseColor, specularColor, perceptualRoughness, metallic, norm, v, normalize(light_dir), specContrib) * sunlit * 3.0 * scol; //magic number to balance with legacy materials
     specContrib *= sunlit * 2.75 * scol;
     specContrib += ibl_spec;
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl b/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
index 385cd51969..b752307d13 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
@@ -44,7 +44,7 @@ vec3 legacy_adjust_fullbright(vec3 c);
 vec3 legacy_adjust(vec3 c);
 vec3 linear_to_srgb(vec3 cl);
 vec3 atmosFragLighting(vec3 light, vec3 additive, vec3 atten);
-void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);
+void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten);
 
 #ifdef HAS_ALPHA_MASK
 uniform float minimum_alpha;
@@ -85,7 +85,7 @@ void main()
     vec3 amblit;
     vec3 additive;
     vec3 atten;
-    calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten, false);
+    calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten);
 #endif
 
 #ifdef WATER_FOG
diff --git a/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl b/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
index ee425f97fc..c8afacf9bb 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
@@ -47,6 +47,6 @@ void main()
     tc.y -= 0.1; // HACK - nudge exposure sample down a little bit to favor ground over sky
     vec3 c = texture(diffuseRect, tc).rgb + texture(emissiveRect, tc).rgb;
     float L = lum(c);
-    frag_color = vec4(L);
+    frag_color = vec4(max(L, 0.0));
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
index e9515a9187..6b960fae33 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
@@ -71,6 +71,7 @@ flat out float vary_sign;
 out vec3 vary_normal;
 
 vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
+vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
 
 
 void main()
@@ -102,9 +103,11 @@ void main()
   	vec3 t = normal_matrix * tangent.xyz;
 #endif //HAS_SKIN
 
-    vary_tangent = normalize(t);
+    n = normalize(n);
+
+    vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0));
     vary_sign = tangent.w;
-    vary_normal = normalize(n);
+    vary_normal = n;
 
 	vertex_color = diffuse_color;
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl
index e2c23ac8f0..160ae7a215 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl
@@ -61,6 +61,7 @@ flat out float vary_sign;
 out vec3 vary_normal;
 
 vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
+vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
 
 void main()
 {
@@ -91,9 +92,11 @@ void main()
 	vec3 t = normal_matrix * tangent.xyz;
 #endif
 
-    vary_tangent = normalize(t);
+    n = normalize(n);
+
+    vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0));
     vary_sign = tangent.w;
-    vary_normal = normalize(n);
+    vary_normal = n;
 	
 	vertex_color = diffuse_color;
 }
@@ -107,8 +110,6 @@ uniform mat4 modelview_projection_matrix;
 uniform mat4 texture_matrix0;
 
 uniform vec4[2] texture_base_color_transform;
-uniform vec4[2] texture_normal_transform;
-uniform vec4[2] texture_metallic_roughness_transform;
 uniform vec4[2] texture_emissive_transform;
 
 in vec3 position;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl b/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
index a32296369c..53e4f02314 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/postDeferredGammaCorrect.glsl
@@ -102,16 +102,12 @@ vec3 toneMap(vec3 color)
 {
 #ifndef NO_POST
     float exp_scale = texture(exposureMap, vec2(0.5,0.5)).r;
-
+    
     color *= exposure * exp_scale;
 
     color = toneMapACES_Hill(color);
-#else
-    color *= 0.6;
 #endif
 
-    color = linear_to_srgb(color);
-
     return color;
 }
 
@@ -158,10 +154,10 @@ float noise(vec2 x) {
 
 vec3 legacyGamma(vec3 color)
 {
-    color = 1. - clamp(color, vec3(0.), vec3(1.));
-    color = 1. - pow(color, vec3(gamma)); // s/b inverted already CPU-side
+    vec3 c = 1. - clamp(color, vec3(0.), vec3(1.));
+    c = 1. - pow(c, vec3(gamma)); // s/b inverted already CPU-side
 
-    return color;
+    return c;
 }
 
 void main() 
@@ -169,12 +165,14 @@ void main()
     //this is the one of the rare spots where diffuseRect contains linear color values (not sRGB)
     vec4 diff = texture(diffuseRect, vary_fragcoord);
 
-    diff.rgb = toneMap(diff.rgb);
-
 #ifdef LEGACY_GAMMA
-#ifndef NO_POST
+    diff.rgb = linear_to_srgb(diff.rgb);
     diff.rgb = legacyGamma(diff.rgb);
+#else
+#ifndef NO_POST
+    diff.rgb = toneMap(diff.rgb);
 #endif
+    diff.rgb = linear_to_srgb(diff.rgb);
 #endif
 
     vec2 tc = vary_fragcoord.xy*screen_res*4.0;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
index 71f7ec52c4..636dfed4ba 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
@@ -76,3 +76,47 @@ vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl
 
     return texcoord;
 }
+
+// Take the rotation only from both transforms and apply to the tangent. This
+// accounts for the change of the topology of the normal texture when a texture
+// rotation is applied to it.
+// *HACK: Assume the imported GLTF model did not have both normal texture
+// transforms and tangent vertices. The use of this function is inconsistent
+// with the GLTF sample viewer when that is the case. See getNormalInfo in
+// https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Viewer/47a191931461a6f2e14de48d6da0f0eb6ec2d147/source/Renderer/shaders/material_info.glsl
+// We may want to account for this case during GLTF model import.
+// -Cosmic,2023-06-06
+vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform)
+{
+    vec2 weights = vec2(0, 1);
+
+    // Apply texture animation first to avoid shearing and other artifacts (rotation only)
+    mat2 sl_rot_scale;
+    sl_rot_scale[0][0] = sl_animation_transform[0][0];
+    sl_rot_scale[0][1] = sl_animation_transform[0][1];
+    sl_rot_scale[1][0] = sl_animation_transform[1][0];
+    sl_rot_scale[1][1] = sl_animation_transform[1][1];
+    weights = sl_rot_scale * weights;
+    // Remove scale
+    weights = normalize(weights);
+
+    // Convert to left-handed coordinate system
+    weights.y = -weights.y;
+
+    // Apply KHR_texture_transform (rotation only)
+    float khr_rotation = khr_gltf_transform[0].z;
+    mat2 khr_rotation_mat = mat2(
+        cos(khr_rotation),-sin(khr_rotation),
+        sin(khr_rotation), cos(khr_rotation)
+    );
+    weights = khr_rotation_mat * weights;
+
+    // Convert back to right-handed coordinate system
+    weights.y = -weights.y;
+
+    // Similar to the MikkTSpace-compatible method of extracting the binormal
+    // from the normal and tangent, as seen in the fragment shader
+    vec3 vertex_binormal = vertex_tangent.w * cross(vertex_normal, vertex_tangent.xyz);
+
+    return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz);
+}
diff --git a/indra/newview/app_settings/shaders/class1/environment/srgbF.glsl b/indra/newview/app_settings/shaders/class1/environment/srgbF.glsl
index 689c345b2c..31b02377da 100644
--- a/indra/newview/app_settings/shaders/class1/environment/srgbF.glsl
+++ b/indra/newview/app_settings/shaders/class1/environment/srgbF.glsl
@@ -113,18 +113,31 @@ vec3 inv_toneMapACES_Hill(vec3 color)
     return color;
 }
 
+// adjust legacy colors to back out tonemapping and exposure 
+//   NOTE: obsolete now that setting probe ambiance to zero removes tonemapping and exposure, but keeping for a minute
+//   while that change goes through testing - davep 6/1/2023
+#define LEGACY_ADJUST 0
+
 vec3 legacy_adjust(vec3 c)
 {
+#if LEGACY_ADJUST
     vec3 desat = rgb2hsv(c.rgb);
     desat.g *= 1.0-(1.0-desat.b)*0.5;
     desat.b += (1.0-desat.b)*0.1f;
     desat.rgb = hsv2rgb(desat);
     return desat;
+#else
+    return c;
+#endif
 }
 
 vec3 legacy_adjust_fullbright(vec3 c)
 {
-    float exp_scale = texture(exposureMap, vec2(0.5, 0.5)).r;
+#if LEGACY_ADJUST
+    float exp_scale = clamp(texture(exposureMap, vec2(0.5, 0.5)).r, 0.01, 10.0);
     return c / exp_scale * 1.34; //magic 1.34 arrived at by binary search for a value that reproduces midpoint grey consistenty
+#else
+    return c;
+#endif
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/lighting/sumLightsV.glsl b/indra/newview/app_settings/shaders/class1/lighting/sumLightsV.glsl
index 0c3ea4231e..75a327d3d7 100644
--- a/indra/newview/app_settings/shaders/class1/lighting/sumLightsV.glsl
+++ b/indra/newview/app_settings/shaders/class1/lighting/sumLightsV.glsl
@@ -38,15 +38,7 @@ vec4 sumLights(vec3 pos, vec3 norm, vec4 color)
 	col.a = color.a;
 	
 	col.rgb = light_diffuse[1].rgb * calcDirectionalLight(norm, light_position[1].xyz);
-	col.rgb = scaleDownLight(col.rgb);
-
-#if defined(LOCAL_LIGHT_KILL)
-    col.rgb = vec3(0);
-#endif
-
-#if !defined(SUNLIGHT_KILL)
-	col.rgb += atmosAffectDirectionalLight(calcDirectionalLight(norm, light_position[0].xyz));
-#endif
+    col.rgb += light_diffuse[1].rgb * sqrt(calcDirectionalLight(norm, -light_position[1].xyz)*0.5+0.25);
 
 	col.rgb = min(col.rgb*color.rgb, 1.0);
 	return col;	
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsF.glsl
index e314555ef9..48cf234aa0 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsF.glsl
@@ -30,7 +30,7 @@ vec3 scaleSoftClipFrag(vec3 light);
 vec3 srgb_to_linear(vec3 col);
 vec3 linear_to_srgb(vec3 col);
 
-uniform int sun_up_factor;
+uniform float sky_hdr_scale;
 
 vec3 atmosFragLighting(vec3 light, vec3 additive, vec3 atten)
 { 
@@ -38,7 +38,7 @@ vec3 atmosFragLighting(vec3 light, vec3 additive, vec3 atten)
     additive = srgb_to_linear(additive*2.0);
     // magic 1.25 here is to match the default RenderSkyHDRScale -- this parameter needs to be plumbed into sky settings or something
     // so it's available to all shaders that call atmosFragLighting instead of just softenLightF.glsl
-    additive *= sun_up_factor*1.25 + 1.0; 
+    additive *= sky_hdr_scale;
     light += additive;
     return light;
 }
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl
index 4e0933f922..437fa0a6d5 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsFuncs.glsl
@@ -25,27 +25,21 @@
 
 uniform vec3  lightnorm;
 uniform vec3  sunlight_color;
-uniform vec3 sunlight_linear;
 uniform vec3  moonlight_color;
-uniform vec3 moonlight_linear;
 uniform int   sun_up_factor;
 uniform vec3  ambient_color;
-uniform vec3 ambient_linear;
 uniform vec3  blue_horizon;
-uniform vec3 blue_horizon_linear;
 uniform vec3  blue_density;
-uniform vec3 blue_density_linear;
 uniform float haze_horizon;
 uniform float haze_density;
-uniform float haze_density_linear;
 uniform float cloud_shadow;
 uniform float density_multiplier;
 uniform float distance_multiplier;
 uniform float max_y;
 uniform vec3  glow;
 uniform float scene_light_strength;
-uniform mat3  ssao_effect_mat;
 uniform float sun_moon_glow_factor;
+uniform float sky_hdr_scale;
 
 float getAmbientClamp() { return 1.0f; }
 
@@ -54,7 +48,7 @@ vec3 legacy_adjust(vec3 col);
 
 // return colors in sRGB space
 void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive,
-                         out vec3 atten, bool use_ao)
+                         out vec3 atten)
 {
     vec3 rel_pos = inPositionEye;
 
@@ -64,7 +58,7 @@ void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, ou
     vec3  rel_pos_norm = normalize(rel_pos);
     float rel_pos_len  = length(rel_pos);
     
-    vec3  sunlight     = (sun_up_factor == 1) ? sunlight_color: moonlight_color * 0.7;  // magic 0.7 to match legacy color
+    vec3  sunlight     = (sun_up_factor == 1) ? sunlight_color: moonlight_color;
     
     // sunlight attenuation effect (hue and brightness) due to atmosphere
     // this is used later for sunlight modulation at various altitudes
@@ -117,20 +111,6 @@ void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, ou
     // increase ambient when there are more clouds
     vec3 tmpAmbient = amb_color + (vec3(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);
-     */
-    if (use_ao)
-    {
-        tmpAmbient = mix(ssao_effect_mat * tmpAmbient.rgb, tmpAmbient.rgb, ambFactor);
-    }
-
     // Similar/Shared Algorithms:
     //     indra\llinventory\llsettingssky.cpp                                        -- LLSettingsSky::calculateLightSettings()
     //     indra\newview\app_settings\shaders\class1\windlight\atmosphericsFuncs.glsl -- calcAtmosphericVars()
@@ -141,7 +121,7 @@ void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, ou
     // brightness of surface both sunlight and ambient
     
     sunlit = sunlight.rgb;
-    amblit = vec3(1,0,1); //should no longer be used, filled in by calcAtmosphericVarsLinear
+    amblit = tmpAmbient;
 
     additive *= vec3(1.0 - combined_haze);
 }
@@ -164,15 +144,16 @@ float ambientLighting(vec3 norm, vec3 light_dir)
 void calcAtmosphericVarsLinear(vec3 inPositionEye, vec3 norm, vec3 light_dir, out vec3 sunlit, out vec3 amblit, out vec3 additive,
                          out vec3 atten)
 {
-    calcAtmosphericVars(inPositionEye, light_dir, 1.0, sunlit, amblit, additive, atten, false);
+    calcAtmosphericVars(inPositionEye, light_dir, 1.0, sunlit, amblit, additive, atten);
 
-    // multiply by 2 to get same colors as when the "scaleSoftClip" implementation was doubling color values
+    // multiply to get similar colors as when the "scaleSoftClip" implementation was doubling color values
     // (allows for mixing of light sources other than sunlight e.g. reflection probes)
-    sunlit *= 2.0;
-
-    // squash ambient to approximate whatever weirdness legacy atmospherics were doing
-    amblit = ambient_color; // * (1.0+sun_up_factor*0.3);
+    sunlit *= 1.5;
+    amblit *= 0.5;
+    
+    // override amblit with ambient_color if sky probe ambiance is not zero
+    amblit = mix(amblit, ambient_color, clamp(sky_hdr_scale-1.0, 0.0, 1.0));
 
-    amblit *= ambientLighting(norm, light_dir);
     amblit = srgb_to_linear(amblit);
+    amblit *= ambientLighting(norm, light_dir);
 }
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsHelpersF.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersF.glsl
index 800d08047a..800d08047a 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsHelpersF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersF.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsHelpersV.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl
index 6ecbfaecb1..6ecbfaecb1 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsHelpersV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsV.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsV.glsl
index 3773f191e8..cc3617ba61 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsV.glsl
@@ -38,7 +38,7 @@ void setPositionEye(vec3 v);
 
 vec3 getAdditiveColor();
 
-void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);
+void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten);
 
 void calcAtmospherics(vec3 inPositionEye) {
     vec3 P = inPositionEye;
@@ -48,7 +48,7 @@ void calcAtmospherics(vec3 inPositionEye) {
     vec3 tmpaddlit = vec3(1);
     vec3 tmpattenlit = vec3(1);
 	vec3 light_dir = (sun_up_factor == 1) ? sun_dir : moon_dir;	
-    calcAtmosphericVars(inPositionEye, light_dir, 1, tmpsunlit, tmpamblit, tmpaddlit, tmpattenlit, false);
+    calcAtmosphericVars(inPositionEye, light_dir, 1, tmpsunlit, tmpamblit, tmpaddlit, tmpattenlit);
     setSunlitColor(tmpsunlit);
     setAmblitColor(tmpamblit);
     setAdditiveColor(tmpaddlit);
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsF.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsF.glsl
index 34669a6796..34669a6796 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsF.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsV.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsV.glsl
index 1b854d80b3..1b854d80b3 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsV.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsWaterF.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsWaterF.glsl
index 7a6741fe0e..7a6741fe0e 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsWaterF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsWaterF.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsWaterV.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsWaterV.glsl
index 23c3aed4d8..23c3aed4d8 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsWaterV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsVarsWaterV.glsl
diff --git a/indra/newview/app_settings/shaders/class2/windlight/gammaF.glsl b/indra/newview/app_settings/shaders/class1/windlight/gammaF.glsl
index 027bfb866f..027bfb866f 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/gammaF.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/gammaF.glsl
diff --git a/indra/newview/app_settings/shaders/class2/deferred/alphaF.glsl b/indra/newview/app_settings/shaders/class2/deferred/alphaF.glsl
index ae8cd97b18..cd57b47eae 100644
--- a/indra/newview/app_settings/shaders/class2/deferred/alphaF.glsl
+++ b/indra/newview/app_settings/shaders/class2/deferred/alphaF.glsl
@@ -274,6 +274,10 @@ void main()
 
     color.rgb = atmosFragLightingLinear(color.rgb, additive, atten);
 
+#ifdef WATER_FOG
+    color = applyWaterFogViewLinear(pos.xyz, color, sunlit_linear);
+#endif // WATER_FOG
+
     vec4 light = vec4(0,0,0,0);
     
    #define LIGHT_LOOP(i) light.rgb += calcPointLightOrSpotLight(light_diffuse[i].rgb, diffuse_linear.rgb, pos.xyz, norm, light_position[i], light_direction[i].xyz, light_attenuation[i].x, light_attenuation[i].y, light_attenuation[i].z, light_attenuation[i].w);
@@ -291,11 +295,6 @@ void main()
     color.rgb += light.rgb;
 #endif // !defined(LOCAL_LIGHT_KILL)
 
-
-#ifdef WATER_FOG
-    color = applyWaterFogViewLinear(pos.xyz, color, sunlit_linear);
-#endif // WATER_FOG
-
 #endif // #else // FOR_IMPOSTOR
 
 #ifdef IS_HUD
diff --git a/indra/newview/app_settings/shaders/class2/deferred/pbralphaF.glsl b/indra/newview/app_settings/shaders/class2/deferred/pbralphaF.glsl
index 7b7b4a040c..d678973515 100644
--- a/indra/newview/app_settings/shaders/class2/deferred/pbralphaF.glsl
+++ b/indra/newview/app_settings/shaders/class2/deferred/pbralphaF.glsl
@@ -84,6 +84,10 @@ vec3 linear_to_srgb(vec3 c);
 void calcAtmosphericVarsLinear(vec3 inPositionEye, vec3 norm, vec3 light_dir, out vec3 sunlit, out vec3 amblit, out vec3 atten, out vec3 additive);
 vec3 atmosFragLightingLinear(vec3 color, vec3 additive, vec3 atten);
 
+#ifdef WATER_FOG
+vec4 applyWaterFogViewLinear(vec3 pos, vec4 color, vec3 sunlit);
+#endif
+
 void calcHalfVectors(vec3 lv, vec3 n, vec3 v, out vec3 h, out vec3 l, out float nh, out float nl, out float nv, out float vh, out float lightDist);
 float calcLegacyDistanceAttenuation(float distance, float falloff);
 float sampleDirectionalShadow(vec3 pos, vec3 norm, vec2 pos_screen);
@@ -148,7 +152,7 @@ vec3 calcPointLightOrSpotLight(vec3 diffuseColor, vec3 specularColor,
         // spot*spot => GL_SPOT_EXPONENT=2
         float spot_atten = spot*spot;
 
-        vec3 intensity = spot_atten * dist_atten * lightColor * 3.9; //magic number to balance with legacy materials
+        vec3 intensity = spot_atten * dist_atten * lightColor * 3.0; //magic number to balance with legacy materials
 
         vec3 speccol;
         color = intensity*pbrPunctual(diffuseColor, specularColor, perceptualRoughness, metallic, n.xyz, v, lv, speccol);
@@ -237,6 +241,11 @@ void main()
 
     color.rgb = atmosFragLightingLinear(color.rgb, additive, atten);
     
+#ifdef WATER_FOG
+    vec4 temp = applyWaterFogViewLinear(pos, vec4(color, 0.0), sunlit_linear);
+    color = temp.rgb;
+#endif
+
     vec3 light = vec3(0);
 
     // Punctual lights
@@ -258,7 +267,7 @@ void main()
     glare = min(glare, 1.0);
     a = max(a, glare);
 
-    frag_color = vec4(color.rgb,a);
+    frag_color = max(vec4(color.rgb,a), vec4(0));
 }
 
 #else
@@ -311,7 +320,7 @@ void main()
     float a = basecolor.a*vertex_color.a;
     color += colorEmissive;
     color = linear_to_srgb(color);
-    frag_color = vec4(color.rgb,a);
+    frag_color = max(vec4(color.rgb,a), vec4(0));
 }
 
 #endif
diff --git a/indra/newview/app_settings/shaders/class3/deferred/fullbrightShinyF.glsl b/indra/newview/app_settings/shaders/class3/deferred/fullbrightShinyF.glsl
index 1c79748b49..0d77e88831 100644
--- a/indra/newview/app_settings/shaders/class3/deferred/fullbrightShinyF.glsl
+++ b/indra/newview/app_settings/shaders/class3/deferred/fullbrightShinyF.glsl
@@ -42,7 +42,7 @@ uniform samplerCube environmentMap;
 vec3 atmosFragLighting(vec3 light, vec3 additive, vec3 atten);
 vec3 legacy_adjust_fullbright(vec3 c);
 vec3 legacy_adjust(vec3 c);
-void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten, bool use_ao);
+void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten);
 
 vec3 linear_to_srgb(vec3 c);
 vec3 srgb_to_linear(vec3 c);
@@ -71,7 +71,7 @@ void main()
     vec3 additive;
     vec3 atten;
     vec3 pos = vary_position;
-    calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten, false);
+    calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten);
 
     float env_intensity = vertex_color.a;
 
diff --git a/indra/newview/app_settings/shaders/class3/deferred/materialF.glsl b/indra/newview/app_settings/shaders/class3/deferred/materialF.glsl
index 77e3b92385..5fb5647d35 100644
--- a/indra/newview/app_settings/shaders/class3/deferred/materialF.glsl
+++ b/indra/newview/app_settings/shaders/class3/deferred/materialF.glsl
@@ -38,7 +38,7 @@ uniform float emissive_brightness;  // fullbright flag, 1.0 == fullbright, 0.0 o
 uniform int sun_up_factor;
 
 #ifdef WATER_FOG
-vec4 applyWaterFogView(vec3 pos, vec4 color);
+vec4 applyWaterFogViewLinear(vec3 pos, vec4 color, vec3 sunlit);
 #endif
 
 vec3 atmosFragLightingLinear(vec3 l, vec3 additive, vec3 atten);
@@ -49,6 +49,7 @@ void calcHalfVectors(vec3 lv, vec3 n, vec3 v, out vec3 h, out vec3 l, out float
 vec3 srgb_to_linear(vec3 cs);
 vec3 linear_to_srgb(vec3 cs);
 vec3 legacy_adjust(vec3 c);
+vec3 legacy_adjust_fullbright(vec3 c);
 
 #if (DIFFUSE_ALPHA_MODE == DIFFUSE_ALPHA_MODE_BLEND)
 
@@ -396,7 +397,7 @@ void main()
     }
 #endif
 
-    color = mix(color.rgb, diffcol.rgb, emissive);
+    color = mix(color.rgb, legacy_adjust_fullbright(diffcol.rgb), emissive);
 
     if (env > 0.0)
     {  // add environmentmap
@@ -410,6 +411,11 @@ void main()
 
     color.rgb = atmosFragLightingLinear(color.rgb, additive, atten); 
 
+#ifdef WATER_FOG
+    vec4 temp = applyWaterFogViewLinear(pos, vec4(color, 0.0), sunlit_linear);
+    color = temp.rgb;
+#endif
+
     vec3 npos = normalize(-pos.xyz);
     vec3 light = vec3(0, 0, 0);
 
@@ -430,11 +436,6 @@ void main()
     glare = min(glare, 1.0);
     float al = max(diffcol.a, glare) * vertex_color.a;
     
-#ifdef WATER_FOG
-    vec4 temp = applyWaterFogView(pos, vec4(color, 0.0));
-    color = temp.rgb;
-#endif
-
     frag_color = max(vec4(color, al), vec4(0));
 
 #else // mode is not DIFFUSE_ALPHA_MODE_BLEND, encode to gbuffer 
diff --git a/indra/newview/app_settings/shaders/class3/deferred/softenLightF.glsl b/indra/newview/app_settings/shaders/class3/deferred/softenLightF.glsl
index 2f3efaa94a..409b46218b 100644
--- a/indra/newview/app_settings/shaders/class3/deferred/softenLightF.glsl
+++ b/indra/newview/app_settings/shaders/class3/deferred/softenLightF.glsl
@@ -25,9 +25,6 @@
 
 #define FLT_MAX 3.402823466e+38
 
-#define REFMAP_COUNT 256
-#define REF_SAMPLE_COUNT 64 //maximum number of samples to consider
-
 out vec4 frag_color;
 
 uniform sampler2D diffuseRect;
@@ -47,9 +44,14 @@ uniform sampler2D     lightFunc;
 uniform float blur_size;
 uniform float blur_fidelity;
 
+#if defined(HAS_SSAO)
+uniform float ssao_irradiance_scale;
+uniform float ssao_irradiance_max;
+#endif
+
 // Inputs
 uniform mat3 env_mat;
-
+uniform mat3  ssao_effect_mat;
 uniform vec3 sun_dir;
 uniform vec3 moon_dir;
 uniform int  sun_up_factor;
@@ -115,6 +117,16 @@ vec3 pbrPunctual(vec3 diffuseColor, vec3 specularColor,
                     vec3 l); //surface point to light
 
 
+void adjustIrradiance(inout vec3 irradiance, vec3 amblit_linear, float ambocc)
+{
+    // use sky settings ambient or irradiance map sample, whichever is brighter
+    irradiance = max(amblit_linear, irradiance);
+
+#if defined(HAS_SSAO)
+    irradiance = mix(ssao_effect_mat * min(irradiance.rgb*ssao_irradiance_scale, vec3(ssao_irradiance_max)), irradiance.rgb, ambocc);
+#endif
+}
+
 void main()
 {
     vec2  tc           = vary_fragcoord.xy;
@@ -176,7 +188,7 @@ void main()
         vec3 orm = texture(specularRect, tc).rgb; 
         float perceptualRoughness = orm.g;
         float metallic = orm.b;
-        float ao = orm.r * ambocc;
+        float ao = orm.r;
 
         vec3 colorEmissive = texture(emissiveRect, tc).rgb;
         // PBR IBL
@@ -184,16 +196,13 @@ void main()
         
         sampleReflectionProbes(irradiance, radiance, tc, pos.xyz, norm.xyz, gloss);
         
-        // Take maximium of legacy ambient vs irradiance sample as irradiance
-        // NOTE: ao is applied in pbrIbl (see pbrBaseLight), do not apply here
-        irradiance       = max(amblit_linear,irradiance);
+        adjustIrradiance(irradiance, amblit_linear, ambocc);
 
         vec3 diffuseColor;
         vec3 specularColor;
         calcDiffuseSpecular(baseColor.rgb, metallic, diffuseColor, specularColor);
 
         vec3 v = -normalize(pos.xyz);
-        color = vec3(1,0,1);
         color = pbrBaseLight(diffuseColor, specularColor, metallic, v, norm.xyz, perceptualRoughness, light_dir, sunlit_linear, scol, radiance, irradiance, colorEmissive, ao, additive, atten);
         
         if (do_atmospherics)
@@ -206,17 +215,15 @@ void main()
         //should only be true of WL sky, just port over base color value
         color = texture(emissiveRect, tc).rgb;
         color = srgb_to_linear(color);
-        if (sun_up_factor > 0)
-        {
-           color *= sky_hdr_scale + 1.0;
-        }
+        color *= sky_hdr_scale;
     }
     else
     {
         // legacy shaders are still writng sRGB to gbuffer
         baseColor.rgb = legacy_adjust(baseColor.rgb);
-
+        
         baseColor.rgb = srgb_to_linear(baseColor.rgb);
+        
         spec.rgb = srgb_to_linear(spec.rgb);
 
         float da          = clamp(dot(norm.xyz, light_dir.xyz), 0.0, 1.0);
@@ -227,11 +234,10 @@ void main()
 
         sampleReflectionProbesLegacy(irradiance, glossenv, legacyenv, tc, pos.xyz, norm.xyz, spec.a, envIntensity);
         
-        // use sky settings ambient or irradiance map sample, whichever is brighter
-        irradiance = max(amblit_linear, irradiance);
+        adjustIrradiance(irradiance, amblit_linear, ambocc);
 
         // apply lambertian IBL only (see pbrIbl)
-        color.rgb = irradiance * ambocc;
+        color.rgb = irradiance;
 
         vec3 sun_contrib = min(da, scol) * sunlit_linear;
         color.rgb += sun_contrib;
diff --git a/indra/newview/app_settings/shaders/class3/lighting/lightV.glsl b/indra/newview/app_settings/shaders/class3/lighting/lightV.glsl
index 30ad493331..77bbbabfae 100644
--- a/indra/newview/app_settings/shaders/class3/lighting/lightV.glsl
+++ b/indra/newview/app_settings/shaders/class3/lighting/lightV.glsl
@@ -23,21 +23,13 @@
  * $/LicenseInfo$
  */
  
-
-
-// All lights, no specular highlights
-vec3 atmosAmbient();
+// used for preview renders only
 vec4 sumLights(vec3 pos, vec3 norm, vec4 color);
-float getAmbientClamp();
 
 vec4 calcLighting(vec3 pos, vec3 norm, vec4 color)
 {
 	vec4 c = sumLights(pos, norm, color);
 
-#if !defined(AMBIENT_KILL)
-    c.rgb += atmosAmbient() * color.rgb * getAmbientClamp();
-#endif
- 
     return c;
 }
 
diff --git a/indra/newview/app_settings/shaders/class3/lighting/sumLightsV.glsl b/indra/newview/app_settings/shaders/class3/lighting/sumLightsV.glsl
deleted file mode 100644
index 4b663dd5b2..0000000000
--- a/indra/newview/app_settings/shaders/class3/lighting/sumLightsV.glsl
+++ /dev/null
@@ -1,67 +0,0 @@
-/**
- * @file class3\lighting\sumLightsV.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
- * $/LicenseInfo$
- */
- 
-
-float calcDirectionalLight(vec3 n, vec3 l);
-float calcPointLightOrSpotLight(vec3 v, vec3 n, vec4 lp, vec3 ln, float la, float fa, float is_pointlight);
-
-vec3 atmosAffectDirectionalLight(float lightIntensity);
-vec3 scaleDownLight(vec3 light);
-
-uniform vec4 light_position[8];
-uniform vec3 light_direction[8];
-uniform vec4 light_attenuation[8]; 
-uniform vec3 light_diffuse[8];
-
-vec4 sumLights(vec3 pos, vec3 norm, vec4 color)
-{
-	vec4 col = vec4(0.0, 0.0, 0.0, color.a);
-	
-	// Collect normal lights (need to be divided by two, as we later multiply by 2)
-	
-	// Collect normal lights
-	col.rgb += light_diffuse[2].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[2], light_direction[2], light_attenuation[2].x, light_attenuation[2].y, light_attenuation[2].z);
-	col.rgb += light_diffuse[3].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[3], light_direction[3], light_attenuation[3].x, light_attenuation[3].y, light_attenuation[3].z);
-	col.rgb += light_diffuse[4].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[4], light_direction[4], light_attenuation[4].x, light_attenuation[4].y, light_attenuation[4].z);
-	col.rgb += light_diffuse[5].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[5], light_direction[5], light_attenuation[5].x, light_attenuation[5].y, light_attenuation[5].z);
-	col.rgb += light_diffuse[6].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[6], light_direction[6], light_attenuation[6].x, light_attenuation[6].y, light_attenuation[6].z);
-	col.rgb += light_diffuse[7].rgb*calcPointLightOrSpotLight(pos.xyz, norm, light_position[7], light_direction[7], light_attenuation[7].x, light_attenuation[7].y, light_attenuation[7].z);
-	col.rgb += light_diffuse[1].rgb*calcDirectionalLight(norm, light_position[1].xyz);
-    col.rgb = scaleDownLight(col.rgb);
-
-#if defined(LOCAL_LIGHT_KILL)
-    col.rgb = vec3(0);
-#endif
-
-	// Add windlight lights
-#if !defined(SUNLIGHT_KILL)
-	col.rgb += atmosAffectDirectionalLight(calcDirectionalLight(norm, light_position[0].xyz));
-#endif
-
-	col.rgb = min(col.rgb*color.rgb, 1.0);
-	
-	return col;	
-}
-