Merge remote-tracking branch 'secondlife/release/2024.06-atlasaurus' into 2024.06-atlasaurus

23 files changed, 343 insertions, 187 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/aoUtil.glsl b/indra/newview/app_settings/shaders/class1/deferred/aoUtil.glsl
index 1c394e1de4..1a065daf89 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/aoUtil.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/aoUtil.glsl
@@ -23,8 +23,7 @@
  * $/LicenseInfo$
  */
 
-uniform sampler2D       noiseMap;
-uniform sampler2D   normalMap;
+uniform sampler2D   noiseMap;
 uniform sampler2D   depthMap;
 
 uniform float ssao_radius;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/avatarShadowF.glsl b/indra/newview/app_settings/shaders/class1/deferred/avatarShadowF.glsl
index 438e1d1b33..37dcbbd328 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/avatarShadowF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/avatarShadowF.glsl
@@ -27,8 +27,6 @@
 
 out vec4 frag_color;
 
-uniform sampler2D diffuseMap;
-
 void main()
 {
     frag_color = vec4(1,1,1,1);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/blurLightF.glsl b/indra/newview/app_settings/shaders/class1/deferred/blurLightF.glsl
index 8627ab1852..23a3ca4911 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/blurLightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/blurLightF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file blurLightF.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
  * $/LicenseInfo$
  */
@@ -27,7 +27,6 @@
 
 out vec4 frag_color;
 
-uniform sampler2D normalMap;
 uniform sampler2D lightMap;
 
 uniform float dist_factor;
@@ -42,16 +41,16 @@ in vec2 vary_fragcoord;
 vec4 getPosition(vec2 pos_screen);
 vec4 getNorm(vec2 pos_screen);
 
-void main() 
+void main()
 {
     vec2 tc = vary_fragcoord.xy;
     vec4 norm = getNorm(tc);
     vec3 pos = getPosition(tc).xyz;
     vec4 ccol = texture(lightMap, tc).rgba;
-  
+
     vec2 dlt = kern_scale * delta / (1.0+norm.xy*norm.xy);
     dlt /= max(-pos.z*dist_factor, 1.0);
-    
+
     vec2 defined_weight = kern[0].xy; // special case the first (centre) sample's weight in the blur; we have to sample it anyway so we get it for 'free'
     vec4 col = defined_weight.xyxx * ccol;
 
@@ -75,15 +74,15 @@ void main()
     k[1] = (k[0]+k[2])*0.5f;
     k[3] = (k[2]+k[4])*0.5f;
     k[5] = (k[4]+k[6])*0.5f;
-    
+
     for (int i = 1; i < 7; i++)
     {
         vec2 samptc = tc + k[i].z*dlt*2.0;
         samptc /= screen_res;
-        vec3 samppos = getPosition(samptc).xyz; 
+        vec3 samppos = getPosition(samptc).xyz;
 
         float d = dot(norm.xyz, samppos.xyz-pos.xyz);// dist from plane
-        
+
         if (d*d <= pointplanedist_tolerance_pow2)
         {
             col += texture(lightMap, samptc)*k[i].xyxx;
@@ -95,10 +94,10 @@ void main()
     {
         vec2 samptc = tc - k[i].z*dlt*2.0;
         samptc /= screen_res;
-        vec3 samppos = getPosition(samptc).xyz; 
+        vec3 samppos = getPosition(samptc).xyz;
 
         float d = dot(norm.xyz, samppos.xyz-pos.xyz);// dist from plane
-        
+
         if (d*d <= pointplanedist_tolerance_pow2)
         {
             col += texture(lightMap, samptc)*k[i].xyxx;
@@ -108,7 +107,7 @@ void main()
 
     col /= defined_weight.xyxx;
     //col.y *= col.y;
-    
+
     frag_color = max(col, vec4(0));
 
 #ifdef IS_AMD_CARD
diff --git a/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl b/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
index 38fbda316b..5193a46ac2 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/deferredUtil.glsl
@@ -50,7 +50,6 @@ SOFTWARE.
 
 uniform sampler2D   normalMap;
 uniform sampler2D   depthMap;
-uniform sampler2D emissiveRect;
 uniform sampler2D projectionMap; // rgba
 uniform sampler2D brdfLut;
 
@@ -487,6 +486,43 @@ vec3 pbrPunctual(vec3 diffuseColor, vec3 specularColor,
     return clamp(color, vec3(0), vec3(10));
 }
 
+vec3 pbrCalcPointLightOrSpotLight(vec3 diffuseColor, vec3 specularColor,
+                    float perceptualRoughness,
+                    float metallic,
+                    vec3 n, // normal
+                    vec3 p, // pixel position
+                    vec3 v, // view vector (negative normalized pixel position)
+                    vec3 lp, // light position
+                    vec3 ld, // light direction (for spotlights)
+                    vec3 lightColor,
+                    float lightSize, float falloff, float is_pointlight, float ambiance)
+{
+    vec3 color = vec3(0,0,0);
+
+    vec3 lv = lp.xyz - p;
+
+    float lightDist = length(lv);
+
+    float dist = lightDist / lightSize;
+    if (dist <= 1.0)
+    {
+        lv /= lightDist;
+
+        float dist_atten = calcLegacyDistanceAttenuation(dist, falloff);
+
+        // spotlight coefficient.
+        float spot = max(dot(-ld, lv), is_pointlight);
+        // spot*spot => GL_SPOT_EXPONENT=2
+        float spot_atten = spot*spot;
+
+        vec3 intensity = spot_atten * dist_atten * lightColor * 3.0; //magic number to balance with legacy materials
+
+        color = intensity*pbrPunctual(diffuseColor, specularColor, perceptualRoughness, metallic, n.xyz, v, lv);
+    }
+
+    return color;
+}
+
 void calcDiffuseSpecular(vec3 baseColor, float metallic, inout vec3 diffuseColor, inout vec3 specularColor)
 {
     vec3 f0 = vec3(0.04);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/exposureF.glsl b/indra/newview/app_settings/shaders/class1/deferred/exposureF.glsl
index eff7221ae7..67890032df 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/exposureF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/exposureF.glsl
@@ -1,28 +1,28 @@
-/** 
+/**
  * @file exposureF.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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]*/
 
 out vec4 frag_color;
@@ -43,7 +43,7 @@ float lum(vec3 col)
     return dot(l, col);
 }
 
-void main() 
+void main()
 {
     vec2 tc = vec2(0.5,0.5);
 
@@ -53,13 +53,13 @@ void main()
     L /= max_L;
     L = pow(L, 2.0);
     float s = mix(dynamic_exposure_params.z, dynamic_exposure_params.y, L);
-    
+
 #ifdef USE_LAST_EXPOSURE
     float prev = texture(exposureMap, vec2(0.5,0.5)).r;
 
     s = mix(prev, s, min(dt*2.0*abs(prev-s), 0.04));
 #endif
-    
+
     frag_color = max(vec4(s, s, s, dt), vec4(0.0));
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl b/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
index 52dfed06ae..2b9cc6ae5a 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/fullbrightF.glsl
@@ -1,28 +1,28 @@
-/** 
+/**
  * @file deferred/fullbrightF.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]*/
 
 out vec4 frag_color;
@@ -52,7 +52,7 @@ vec4 applySkyAndWaterFog(vec3 pos, vec3 additive, vec3 atten, vec4 color);
 
 void mirrorClip(vec3 pos);
 
-void main() 
+void main()
 {
     mirrorClip(vary_position);
 #ifdef IS_ALPHA
@@ -90,7 +90,7 @@ void main()
     calcAtmosphericVars(pos.xyz, vec3(0), 1.0, sunlit, amblit, additive, atten);
 
     color.rgb = applySkyAndWaterFog(pos, additive, atten, color).rgb;
-    
+
 #endif
 
 #endif
diff --git a/indra/newview/app_settings/shaders/class1/deferred/globalF.glsl b/indra/newview/app_settings/shaders/class1/deferred/globalF.glsl
index e407dad21c..d493976eba 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/globalF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/globalF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1/deferred/globalF.glsl
  *
  * $LicenseInfo:firstyear=2024&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2024, 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
  * $/LicenseInfo$
  */
diff --git a/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl b/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
index 95b2f80e06..3432bf07ef 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/luminanceF.glsl
@@ -1,32 +1,32 @@
-/** 
+/**
  * @file luminanceF.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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]*/
 
-// take a luminance sample of diffuseRect and emissiveRect 
+// take a luminance sample of diffuseRect and emissiveRect
 
 out vec4 frag_color;
 
@@ -43,12 +43,12 @@ float lum(vec3 col)
     return dot(l, col);
 }
 
-void main() 
+void main()
 {
     vec2 tc = vary_fragcoord*0.6+0.2;
     tc.y -= 0.1; // HACK - nudge exposure sample down a little bit to favor ground over sky
     vec3 c = texture(diffuseRect, tc).rgb;
-    
+
     vec4  norm         = texture(normalMap, tc);
 
     if (!GET_GBUFFER_FLAG(GBUFFER_FLAG_HAS_HDRI) &&
diff --git a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
index 6ef556d7e8..585de99e1d 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/moonF.glsl
@@ -1,28 +1,28 @@
-/** 
+/**
  * @file class1\deferred\moonF.glsl
  *
  * $LicenseInfo:firstyear=2005&license=viewerlgpl$
  * Second Life Viewer Source Code
  * 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
  * 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]*/
 
 out vec4 frag_data[4];
@@ -34,7 +34,7 @@ uniform sampler2D diffuseMap;
 
 in vec2 vary_texcoord0;
 
-void main() 
+void main()
 {
     // Restore Pre-EEP alpha fade moon near horizon
     float fade = 1.0;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrShadowAlphaMaskF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrShadowAlphaMaskF.glsl
index 35b7602569..07a2218db2 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrShadowAlphaMaskF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrShadowAlphaMaskF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file pbrShadowAlphaMaskF.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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
  * $/LicenseInfo$
  */
@@ -33,7 +33,7 @@ in vec4 vertex_color;
 in vec2 vary_texcoord0;
 uniform float minimum_alpha;
 
-void main() 
+void main()
 {
     float alpha = texture(diffuseMap,vary_texcoord0.xy).a * vertex_color.a;
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
index d0fc362db9..ae179d3f37 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
@@ -51,8 +51,6 @@ uniform vec4[2] texture_emissive_transform;
 
 out vec3 vary_fragcoord;
 
-uniform float near_clip;
-
 in vec3 position;
 in vec4 diffuse_color;
 in vec3 normal;
@@ -88,7 +86,7 @@ void main()
 #endif
     gl_Position = vert;
 
-    vary_fragcoord.xyz = vert.xyz + vec3(0,0,near_clip);
+    vary_fragcoord.xyz = vert.xyz;
 
     base_color_texcoord = texture_transform(texcoord0, texture_base_color_transform, texture_matrix0);
     normal_texcoord = texture_transform(texcoord0, texture_normal_transform, texture_matrix0);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueF.glsl
index 380d493636..b521081af9 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file pbropaqueF.glsl
  *
  * $LicenseInfo:firstyear=2022&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2022, 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
  * $/LicenseInfo$
  */
@@ -28,7 +28,7 @@
 
 #ifndef IS_HUD
 
-// deferred opaque implementation 
+// deferred opaque implementation
 
 uniform sampler2D diffuseMap;  //always in sRGB space
 
@@ -85,7 +85,7 @@ void main()
     float sign = vary_sign;
     vec3 vN = vary_normal;
     vec3 vT = vary_tangent.xyz;
-    
+
     vec3 vB = sign * cross(vN, vT);
     vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN );
 
@@ -95,7 +95,7 @@ void main()
     //   roughness 0.0
     //   metal     0.0
     vec3 spec = texture(specularMap, metallic_roughness_texcoord.xy).rgb;
-    
+
     spec.g *= roughnessFactor;
     spec.b *= metallicFactor;
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
index 0de2d348c3..2cb7ff196b 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1\deferred\terrainF.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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
  * $/LicenseInfo$
  */
@@ -31,7 +31,7 @@
 #define TERRAIN_PBR_DETAIL_METALLIC_ROUGHNESS -3
 
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-#define TerrainCoord vec4[2]
+#define TerrainCoord vec4[3]
 #elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
 #define TerrainCoord vec2
 #endif
@@ -131,12 +131,16 @@ uniform vec3[4] emissiveColors;
 uniform vec4 minimum_alphas; // PBR alphaMode: MASK, See: mAlphaCutoff, setAlphaCutoff()
 
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+in vec4[10] vary_coords;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
 in vec4[2] vary_coords;
 #endif
 in vec3 vary_position;
 in vec3 vary_normal;
-in vec3 vary_tangent;
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+in vec3 vary_tangents[4];
 flat in float vary_sign;
+#endif
 in vec4 vary_texcoord0;
 in vec4 vary_texcoord1;
 
@@ -144,17 +148,26 @@ void mirrorClip(vec3 position);
 
 float terrain_mix(TerrainMix tm, vec4 tms4);
 
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+// from mikktspace.com
+vec3 mikktspace(vec3 vNt, vec3 vT)
+{
+    vec3 vN = vary_normal;
+
+    vec3 vB = vary_sign * cross(vN, vT);
+    vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN );
+
+    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
+
+    return tnorm;
+}
+#endif
+
 void main()
 {
     // Make sure we clip the terrain if we're in a mirror.
     mirrorClip(vary_position);
 
-#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-    TerrainCoord terrain_texcoord = vary_coords;
-#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
-    TerrainCoord terrain_texcoord = vary_texcoord0.xy;
-#endif
-
     float alpha1 = texture(alpha_ramp, vary_texcoord0.zw).a;
     float alpha2 = texture(alpha_ramp,vary_texcoord1.xy).a;
     float alphaFinal = texture(alpha_ramp, vary_texcoord1.zw).a;
@@ -182,9 +195,19 @@ void main()
 
     PBRMix pbr_mix = init_pbr_mix();
     PBRMix mix2;
+    TerrainCoord terrain_texcoord;
     switch (tm.type & MIX_X)
     {
     case MIX_X:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        terrain_texcoord[0].xy = vary_coords[0].xy;
+        terrain_texcoord[0].zw = vary_coords[0].zw;
+        terrain_texcoord[1].xy = vary_coords[1].xy;
+        terrain_texcoord[1].zw = vary_coords[1].zw;
+        terrain_texcoord[2].xy = vary_coords[2].xy;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        terrain_texcoord = vary_coords[0].xy;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_0_base_color
@@ -207,6 +230,9 @@ void main()
             , emissiveColors[0]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[0]);
+#endif
         pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.x);
         break;
     default:
@@ -215,6 +241,15 @@ void main()
     switch (tm.type & MIX_Y)
     {
     case MIX_Y:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        terrain_texcoord[0].xy = vary_coords[2].zw;
+        terrain_texcoord[0].zw = vary_coords[3].xy;
+        terrain_texcoord[1].xy = vary_coords[3].zw;
+        terrain_texcoord[1].zw = vary_coords[4].xy;
+        terrain_texcoord[2].xy = vary_coords[4].zw;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        terrain_texcoord = vary_coords[0].zw;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_1_base_color
@@ -237,6 +272,9 @@ void main()
             , emissiveColors[1]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[1]);
+#endif
         pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.y);
         break;
     default:
@@ -245,6 +283,15 @@ void main()
     switch (tm.type & MIX_Z)
     {
     case MIX_Z:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        terrain_texcoord[0].xy = vary_coords[5].xy;
+        terrain_texcoord[0].zw = vary_coords[5].zw;
+        terrain_texcoord[1].xy = vary_coords[6].xy;
+        terrain_texcoord[1].zw = vary_coords[6].zw;
+        terrain_texcoord[2].xy = vary_coords[7].xy;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        terrain_texcoord = vary_coords[1].xy;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_2_base_color
@@ -267,6 +314,9 @@ void main()
             , emissiveColors[2]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[2]);
+#endif
         pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.z);
         break;
     default:
@@ -275,6 +325,15 @@ void main()
     switch (tm.type & MIX_W)
     {
     case MIX_W:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        terrain_texcoord[0].xy = vary_coords[7].zw;
+        terrain_texcoord[0].zw = vary_coords[8].xy;
+        terrain_texcoord[1].xy = vary_coords[8].zw;
+        terrain_texcoord[1].zw = vary_coords[9].xy;
+        terrain_texcoord[2].xy = vary_coords[9].zw;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        terrain_texcoord = vary_coords[1].zw;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_3_base_color
@@ -297,6 +356,9 @@ void main()
             , emissiveColors[3]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[3]);
+#endif
         pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.w);
         break;
     default:
@@ -311,20 +373,12 @@ void main()
     float base_color_factor_alpha = terrain_mix(tm, vec4(baseColorFactors[0].z, baseColorFactors[1].z, baseColorFactors[2].z, baseColorFactors[3].z));
 
 #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
-    // from mikktspace.com
-    vec3 vNt = pbr_mix.vNt;
-    vec3 vN = vary_normal;
-    vec3 vT = vary_tangent.xyz;
-    
-    vec3 vB = vary_sign * cross(vN, vT);
-    vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN );
-
-    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
+    vec3 tnorm = normalize(pbr_mix.vNt);
 #else
     vec3 tnorm = vary_normal;
-    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
 #endif
-   
+    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
+
 
 #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE)
 #define mix_emissive pbr_mix.emissive
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
index 04eb135c90..d1a380bf94 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1\deferred\pbrterrainUtilF.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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
  * $/LicenseInfo$
  */
@@ -233,17 +233,12 @@ float terrain_mix(TerrainMix tm, vec4 tms4)
 // Triplanar mapping
 
 // Pre-transformed texture coordinates for each axial uv slice (Packing: xy, yz, (-x)z, unused)
-#define TerrainCoord vec4[2]
+#define TerrainCoord vec4[3]
 
-vec2 _t_uv(vec2 uv_unflipped, float sign_or_zero)
+// If sign_or_zero is positive, use uv_unflippped, otherwise use uv_flipped
+vec2 _t_uv(vec2 uv_unflipped, vec2 uv_flipped, float sign_or_zero)
 {
-    // Handle case where sign is 0
-    float sign = (2.0*sign_or_zero) + 1.0;
-    sign /= abs(sign);
-    // If the vertex normal is negative, flip the texture back
-    // right-side up.
-    vec2 uv = uv_unflipped * vec2(sign, 1);
-    return uv;
+    return mix(uv_flipped, uv_unflipped, max(0.0, sign_or_zero));
 }
 
 vec3 _t_normal_post_1(vec3 vNt0, float sign_or_zero)
@@ -298,9 +293,9 @@ PBRMix terrain_sample_pbr(
 {
     PBRMix mix = init_pbr_mix();
 
-#define get_uv_x() _t_uv(terrain_coord[0].zw, sign(vary_vertex_normal.x))
-#define get_uv_y() _t_uv(terrain_coord[1].xy, sign(vary_vertex_normal.y))
-#define get_uv_z() _t_uv(terrain_coord[0].xy, sign(vary_vertex_normal.z))
+#define get_uv_x() _t_uv(terrain_coord[0].zw, terrain_coord[1].zw, sign(vary_vertex_normal.x))
+#define get_uv_y() _t_uv(terrain_coord[1].xy, terrain_coord[2].xy, sign(vary_vertex_normal.y))
+#define get_uv_z() _t_uv(terrain_coord[0].xy, vec2(0),             sign(vary_vertex_normal.z))
     switch (tw.type & SAMPLE_X)
     {
     case SAMPLE_X:
@@ -379,7 +374,7 @@ PBRMix terrain_sample_pbr(
     default:
         break;
     }
-    
+
     return mix;
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
index ed52297314..f8e826bbdb 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
@@ -23,6 +23,11 @@
  * $/LicenseInfo$
  */
 
+#define TERRAIN_PBR_DETAIL_EMISSIVE 0
+#define TERRAIN_PBR_DETAIL_OCCLUSION -1
+#define TERRAIN_PBR_DETAIL_NORMAL -2
+#define TERRAIN_PBR_DETAIL_METALLIC_ROUGHNESS -3
+
 uniform mat3 normal_matrix;
 uniform mat4 texture_matrix0;
 uniform mat4 modelview_matrix;
@@ -34,21 +39,25 @@ in vec4 tangent;
 in vec4 diffuse_color;
 in vec2 texcoord1;
 
-#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-out vec4[2] vary_coords;
-#endif
 out vec3 vary_vertex_normal; // Used by pbrterrainUtilF.glsl
 out vec3 vary_normal;
-out vec3 vary_tangent;
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+out vec3 vary_tangents[4];
 flat out float vary_sign;
+#endif
 out vec4 vary_texcoord0;
 out vec4 vary_texcoord1;
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+out vec4[10] vary_coords;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+out vec4[2] vary_coords;
+#endif
 out vec3 vary_position;
 
-// *HACK: tangent_space_transform should use texture_normal_transform, or maybe
-// we shouldn't use tangent_space_transform at all. See the call to
-// tangent_space_transform below.
-uniform vec4[2] texture_base_color_transform;
+// *HACK: Each material uses only one texture transform, but the KHR texture
+// transform spec allows handling texture transforms separately for each
+// individual texture info.
+uniform vec4[5] terrain_texture_transforms;
 
 vec2 terrain_texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform);
 vec3 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform);
@@ -63,31 +72,101 @@ void main()
     vary_vertex_normal = normal;
     vec3 t = normal_matrix * tangent.xyz;
 
-    vary_tangent = normalize(t);
-    // *TODO: Decide if we want this. It may be better to just calculate the
-    // tangents on-the-fly in the fragment shader, due to the subtleties of the
-    // effect of triplanar mapping on UVs.
-    // *HACK: Should be using texture_normal_transform here. The KHR texture
-    // transform spec requires handling texture transforms separately for each
-    // individual texture.
-    vary_tangent = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, texture_base_color_transform));
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+    {
+        vec4[2] ttt;
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_tangents[0] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_tangents[1] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_tangents[2] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_tangents[3] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+    }
+
     vary_sign = tangent.w;
+#endif
     vary_normal = normalize(n);
 
     // Transform and pass tex coords
-    // *HACK: texture_base_color_transform is used for all of these here, but
-    // the KHR texture transform spec requires handling texture transforms
-    // separately for each individual texture.
+    {
+        vec4[2] ttt;
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-    // xy
-    vary_coords[0].xy = terrain_texture_transform(position.xy, texture_base_color_transform);
-    // yz
-    vary_coords[0].zw = terrain_texture_transform(position.yz, texture_base_color_transform);
-    // (-x)z
-    vary_coords[1].xy = terrain_texture_transform(position.xz * vec2(-1, 1), texture_base_color_transform);
+// Don't care about upside-down (transform_xy_flipped())
+#define transform_xy()             terrain_texture_transform(position.xy,               ttt)
+#define transform_yz()             terrain_texture_transform(position.yz,               ttt)
+#define transform_negx_z()         terrain_texture_transform(position.xz * vec2(-1, 1), ttt)
+#define transform_yz_flipped()     terrain_texture_transform(position.yz * vec2(-1, 1), ttt)
+#define transform_negx_z_flipped() terrain_texture_transform(position.xz,               ttt)
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_coords[0].xy = transform_xy();
+        vary_coords[0].zw = transform_yz();
+        vary_coords[1].xy = transform_negx_z();
+        vary_coords[1].zw = transform_yz_flipped();
+        vary_coords[2].xy = transform_negx_z_flipped();
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_coords[2].zw = transform_xy();
+        vary_coords[3].xy = transform_yz();
+        vary_coords[3].zw = transform_negx_z();
+        vary_coords[4].xy = transform_yz_flipped();
+        vary_coords[4].zw = transform_negx_z_flipped();
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_coords[5].xy = transform_xy();
+        vary_coords[5].zw = transform_yz();
+        vary_coords[6].xy = transform_negx_z();
+        vary_coords[6].zw = transform_yz_flipped();
+        vary_coords[7].xy = transform_negx_z_flipped();
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_coords[7].zw = transform_xy();
+        vary_coords[8].xy = transform_yz();
+        vary_coords[8].zw = transform_negx_z();
+        vary_coords[9].xy = transform_yz_flipped();
+        vary_coords[9].zw = transform_negx_z_flipped();
 #elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
-    vary_texcoord0.xy = terrain_texture_transform(position.xy, texture_base_color_transform);
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_coords[0].xy = terrain_texture_transform(position.xy, ttt);
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_coords[0].zw = terrain_texture_transform(position.xy, ttt);
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_coords[1].xy = terrain_texture_transform(position.xy, ttt);
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_coords[1].zw = terrain_texture_transform(position.xy, ttt);
 #endif
+    }
 
     vec4 tc = vec4(texcoord1,0,1);
     vary_texcoord0.zw = tc.xy;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/screenSpaceReflUtil.glsl b/indra/newview/app_settings/shaders/class1/deferred/screenSpaceReflUtil.glsl
index a33c4cc58b..6791fe44d9 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/screenSpaceReflUtil.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/screenSpaceReflUtil.glsl
@@ -27,11 +27,11 @@
 
 float random (vec2 uv) 
 {
-    return 0.;
+    return 0.f;
 }
 
 float tapScreenSpaceReflection(int totalSamples, vec2 tc, vec3 viewPos, vec3 n, inout vec4 collectedColor, sampler2D source, float glossiness)
 {
     collectedColor = vec4(0);
-    return 0.;
+    return 0.f;
 }
diff --git a/indra/newview/app_settings/shaders/class1/deferred/shadowAlphaMaskF.glsl b/indra/newview/app_settings/shaders/class1/deferred/shadowAlphaMaskF.glsl
index 9db8f461dd..f208ac746b 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/shadowAlphaMaskF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/shadowAlphaMaskF.glsl
@@ -27,8 +27,6 @@
 
 out vec4 frag_color;
 
-uniform sampler2D diffuseMap;
-
 in vec4 post_pos;
 in float target_pos_x;
 in vec4 vertex_color;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/shadowUtil.glsl b/indra/newview/app_settings/shaders/class1/deferred/shadowUtil.glsl
index 16cc7cfbbc..6f7bd2bf3c 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/shadowUtil.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/shadowUtil.glsl
@@ -24,7 +24,6 @@
  */
 
 uniform sampler2D   normalMap;
-uniform sampler2D   depthMap;
 
 #if defined(SUN_SHADOW)
 uniform sampler2DShadow shadowMap0;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl b/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
index 785c748234..41e42b5173 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/skyF.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1/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
  * $/LicenseInfo$
  */
@@ -99,9 +99,9 @@ void main()
     else
 #endif
     {
-        // Potential Fill-rate optimization.  Add cloud calculation 
-        // back in and output alpha of 0 (so that alpha culling kills 
-        // the fragment) if the sky wouldn't show up because the clouds 
+        // Potential Fill-rate optimization.  Add cloud calculation
+        // back in and output alpha of 0 (so that alpha culling kills
+        // the fragment) if the sky wouldn't show up because the clouds
         // are fully opaque.
 
         color = vary_HazeColor;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
index 24d2db2183..ea00d240df 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/skyV.glsl
@@ -102,7 +102,7 @@ void main()
 
     // Initialize temp variables
     vec3 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color * 0.7; //magic 0.7 to match legacy color
-    
+
     // Sunlight attenuation effect (hue and brightness) due to atmosphere
     // this is used later for sunlight modulation at various altitudes
     vec3 light_atten = (blue_density + vec3(haze_density * 0.25)) * (density_multiplier * max_y);
@@ -152,7 +152,7 @@ void main()
     sunlight *= max(0.0, (1. - cloud_shadow));
 
     // Haze color below cloud
-    vec3 add_below_cloud = (blue_horizon * blue_weight * (sunlight + ambient) 
+    vec3 add_below_cloud = (blue_horizon * blue_weight * (sunlight + ambient)
                          + (haze_horizon * haze_weight) * (sunlight * haze_glow + ambient));
 
     // Attenuate cloud color by atmosphere
diff --git a/indra/newview/app_settings/shaders/class1/deferred/terrainF.glsl b/indra/newview/app_settings/shaders/class1/deferred/terrainF.glsl
index 5f598f84a7..1fd31e0546 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/terrainF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/terrainF.glsl
@@ -1,28 +1,28 @@
-/** 
+/**
  * @file class1\deferred\terrainF.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]*/
 
 out vec4 frag_data[4];
@@ -44,7 +44,7 @@ void main()
 {
     mirrorClip(pos);
     /// Note: This should duplicate the blending functionality currently used for the terrain rendering.
-    
+
     vec4 color0 = texture(detail_0, vary_texcoord0.xy);
     vec4 color1 = texture(detail_1, vary_texcoord0.xy);
     vec4 color2 = texture(detail_2, vary_texcoord0.xy);
@@ -54,10 +54,10 @@ void main()
     float alpha2 = texture(alpha_ramp,vary_texcoord1.xy).a;
     float alphaFinal = texture(alpha_ramp, vary_texcoord1.zw).a;
     vec4 outColor = mix( mix(color3, color2, alpha2), mix(color1, color0, alpha1), alphaFinal );
-   
-    outColor.a = 0.0; // yes, downstream atmospherics 
-    
-    frag_data[0] = outColor;
+
+    outColor.a = 0.0; // yes, downstream atmospherics
+
+    frag_data[0] = max(outColor, vec4(0));
     frag_data[1] = vec4(0.0,0.0,0.0,-1.0);
     vec3 nvn = normalize(vary_normal);
     frag_data[2] = vec4(nvn.xyz, GBUFFER_FLAG_HAS_ATMOS);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/terrainV.glsl b/indra/newview/app_settings/shaders/class1/deferred/terrainV.glsl
index b4ab7cd169..7fc0e98513 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/terrainV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/terrainV.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1\environment\terrainV.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
  * $/LicenseInfo$
  */
@@ -44,15 +44,15 @@ uniform vec4 object_plane_t;
 vec2 texgen_object(vec4 vpos, mat4 mat, vec4 tp0, vec4 tp1)
 {
     vec4 tcoord;
-    
+
     tcoord.x = dot(vpos, tp0);
     tcoord.y = dot(vpos, tp1);
     tcoord.z = 0;
     tcoord.w = 1;
 
-    tcoord = mat * tcoord; 
-    
-    return tcoord.xy; 
+    tcoord = mat * tcoord;
+
+    return tcoord.xy;
 }
 
 void main()
@@ -65,12 +65,12 @@ void main()
     pos = (modelview_matrix*pre_pos).xyz;
 
     vary_normal = normalize(normal_matrix * normal);
-    
+
     // Transform and pass tex coords
     vary_texcoord0.xy = texgen_object(vec4(position, 1.0), texture_matrix0, object_plane_s, object_plane_t);
-    
+
     vec4 t = vec4(texcoord1,0,1);
-    
+
     vary_texcoord0.zw = t.xy;
     vary_texcoord1.xy = t.xy-vec2(2.0, 0.0);
     vary_texcoord1.zw = t.xy-vec2(1.0, 0.0);
diff --git a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
index 7c02cb9d4a..767416d564 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
@@ -1,24 +1,24 @@
-/** 
+/**
  * @file class1/deferred/textureUtilV.glsl
  *
  * $LicenseInfo:firstyear=2023&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2023, 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
  * $/LicenseInfo$
  */
@@ -48,6 +48,7 @@ vec2 khr_texture_transform(vec2 texcoord, vec2 scale, float rotation, vec2 offse
     return (transform * vec3(texcoord, 1)).xy;
 }
 
+// A texture transform function for PBR materials applied to shape prims/Collada model prims
 // vertex_texcoord - The UV texture coordinates sampled from the vertex at
 //     runtime. Per SL convention, this is in a right-handed UV coordinate
 //     system. Collada models also have right-handed UVs.
@@ -134,7 +135,7 @@ vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] kh
     return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz);
 }
 
-// Similar to tangent_space_transform but no no texture animation support.
+// Similar to tangent_space_transform but no texture animation support.
 vec3 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform)
 {
     // Immediately convert to left-handed coordinate system ((0,1) -> (0, -1))