Merge branch 'master' into DRTVWR-513-maint

# Conflicts:
#	indra/newview/llgroupmgr.cpp

1 files changed, 443 insertions, 439 deletions

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
+}
+