Additional water fixes and tweaks. (#3524)

* Incorporation of feedback for #3456

8 files changed, 325 insertions, 317 deletions

diff --git a/indra/llrender/llglslshader.h b/indra/llrender/llglslshader.h
index 58c456f134..873ab0cff5 100644
--- a/indra/llrender/llglslshader.h
+++ b/indra/llrender/llglslshader.h
@@ -59,6 +59,7 @@ public:
     bool attachNothing = false;
     bool hasHeroProbes = false;
     bool isPBRTerrain = false;
+    bool hasTonemap = false;
 };
 
 // ============= Structure for caching shader uniforms ===============
diff --git a/indra/llrender/llshadermgr.cpp b/indra/llrender/llshadermgr.cpp
index 25d8ccd4b3..4807c12226 100644
--- a/indra/llrender/llshadermgr.cpp
+++ b/indra/llrender/llshadermgr.cpp
@@ -291,6 +291,14 @@ bool LLShaderMgr::attachShaderFeatures(LLGLSLShader * shader)
         }
     }
 
+    if (features->hasTonemap)
+    {
+        if (!shader->attachFragmentObject("deferred/tonemapUtilF.glsl"))
+        {
+            return false;
+        }
+    }
+
     // NOTE order of shader object attaching is VERY IMPORTANT!!!
     if (features->hasAtmospherics)
     {
diff --git a/indra/newview/app_settings/shaders/class1/deferred/postDeferredTonemap.glsl b/indra/newview/app_settings/shaders/class1/deferred/postDeferredTonemap.glsl
index fc6d4d7727..c4610bffac 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/postDeferredTonemap.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/postDeferredTonemap.glsl
@@ -28,138 +28,11 @@
 out vec4 frag_color;
 
 uniform sampler2D diffuseRect;
-uniform sampler2D exposureMap;
 
-uniform vec2 screen_res;
 in vec2 vary_fragcoord;
 
 vec3 linear_to_srgb(vec3 cl);
-
-//===============================================================
-// tone mapping taken from Khronos sample implementation
-//===============================================================
-
-// sRGB => XYZ => D65_2_D60 => AP1 => RRT_SAT
-const mat3 ACESInputMat = mat3
-(
-    0.59719, 0.07600, 0.02840,
-    0.35458, 0.90834, 0.13383,
-    0.04823, 0.01566, 0.83777
-);
-
-
-// ODT_SAT => XYZ => D60_2_D65 => sRGB
-const mat3 ACESOutputMat = mat3
-(
-    1.60475, -0.10208, -0.00327,
-    -0.53108,  1.10813, -0.07276,
-    -0.07367, -0.00605,  1.07602
-);
-
-// ACES tone map (faster approximation)
-// see: https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/
-vec3 toneMapACES_Narkowicz(vec3 color)
-{
-    const float A = 2.51;
-    const float B = 0.03;
-    const float C = 2.43;
-    const float D = 0.59;
-    const float E = 0.14;
-    return clamp((color * (A * color + B)) / (color * (C * color + D) + E), 0.0, 1.0);
-}
-
-
-// ACES filmic tone map approximation
-// see https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl
-vec3 RRTAndODTFit(vec3 color)
-{
-    vec3 a = color * (color + 0.0245786) - 0.000090537;
-    vec3 b = color * (0.983729 * color + 0.4329510) + 0.238081;
-    return a / b;
-}
-
-
-// tone mapping
-vec3 toneMapACES_Hill(vec3 color)
-{
-    color = ACESInputMat * color;
-
-    // Apply RRT and ODT
-    color = RRTAndODTFit(color);
-
-    color = ACESOutputMat * color;
-
-    // Clamp to [0, 1]
-    color = clamp(color, 0.0, 1.0);
-
-    return color;
-}
-
-// Khronos Neutral tonemapping
-// https://github.com/KhronosGroup/ToneMapping/tree/main
-// Input color is non-negative and resides in the Linear Rec. 709 color space.
-// Output color is also Linear Rec. 709, but in the [0, 1] range.
-vec3 PBRNeutralToneMapping( vec3 color )
-{
-  const float startCompression = 0.8 - 0.04;
-  const float desaturation = 0.15;
-
-  float x = min(color.r, min(color.g, color.b));
-  float offset = x < 0.08 ? x - 6.25 * x * x : 0.04;
-  color -= offset;
-
-  float peak = max(color.r, max(color.g, color.b));
-  if (peak < startCompression) return color;
-
-  const float d = 1. - startCompression;
-  float newPeak = 1. - d * d / (peak + d - startCompression);
-  color *= newPeak / peak;
-
-  float g = 1. - 1. / (desaturation * (peak - newPeak) + 1.);
-  return mix(color, newPeak * vec3(1, 1, 1), g);
-}
-
-uniform float exposure;
-uniform float tonemap_mix;
-uniform int tonemap_type;
-
-vec3 toneMap(vec3 color)
-{
-#ifndef NO_POST
-    float exp_scale = texture(exposureMap, vec2(0.5,0.5)).r;
-
-    color *= exposure * exp_scale;
-
-    vec3 clamped_color = clamp(color.rgb, vec3(0.0), vec3(1.0));
-
-    switch(tonemap_type)
-    {
-    case 0:
-        color = PBRNeutralToneMapping(color);
-        break;
-    case 1:
-        color = toneMapACES_Hill(color);
-        break;
-    }
-
-    // mix tonemapped and linear here to provide adjustment
-    color = mix(clamped_color, color, tonemap_mix);
-#endif
-
-    return color;
-}
-
-//===============================================================
-
-void debugExposure(inout vec3 color)
-{
-    float exp_scale = texture(exposureMap, vec2(0.5,0.5)).r;
-    exp_scale *= 0.5;
-    if (abs(vary_fragcoord.y-exp_scale) < 0.01 && vary_fragcoord.x < 0.1)
-    {
-        color = vec3(1,0,0);
-    }
-}
+vec3 toneMap(vec3 color);
 
 void main()
 {
diff --git a/indra/newview/app_settings/shaders/class1/deferred/tonemapUtilF.glsl b/indra/newview/app_settings/shaders/class1/deferred/tonemapUtilF.glsl
new file mode 100644
index 0000000000..a63b8d7c2b
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/deferred/tonemapUtilF.glsl
@@ -0,0 +1,180 @@
+/**
+ * @file postDeferredTonemap.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
+ * $/LicenseInfo$
+ */
+
+/*[EXTRA_CODE_HERE]*/
+
+uniform sampler2D exposureMap;
+uniform vec2 screen_res;
+in vec2 vary_fragcoord;
+
+//===============================================================
+// tone mapping taken from Khronos sample implementation
+//===============================================================
+
+// sRGB => XYZ => D65_2_D60 => AP1 => RRT_SAT
+const mat3 ACESInputMat = mat3
+(
+    0.59719, 0.07600, 0.02840,
+    0.35458, 0.90834, 0.13383,
+    0.04823, 0.01566, 0.83777
+);
+
+
+// ODT_SAT => XYZ => D60_2_D65 => sRGB
+const mat3 ACESOutputMat = mat3
+(
+    1.60475, -0.10208, -0.00327,
+    -0.53108,  1.10813, -0.07276,
+    -0.07367, -0.00605,  1.07602
+);
+
+// ACES tone map (faster approximation)
+// see: https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/
+vec3 toneMapACES_Narkowicz(vec3 color)
+{
+    const float A = 2.51;
+    const float B = 0.03;
+    const float C = 2.43;
+    const float D = 0.59;
+    const float E = 0.14;
+    return clamp((color * (A * color + B)) / (color * (C * color + D) + E), 0.0, 1.0);
+}
+
+
+// ACES filmic tone map approximation
+// see https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl
+vec3 RRTAndODTFit(vec3 color)
+{
+    vec3 a = color * (color + 0.0245786) - 0.000090537;
+    vec3 b = color * (0.983729 * color + 0.4329510) + 0.238081;
+    return a / b;
+}
+
+
+// tone mapping
+vec3 toneMapACES_Hill(vec3 color)
+{
+    color = ACESInputMat * color;
+
+    // Apply RRT and ODT
+    color = RRTAndODTFit(color);
+
+    color = ACESOutputMat * color;
+
+    // Clamp to [0, 1]
+    color = clamp(color, 0.0, 1.0);
+
+    return color;
+}
+
+// Khronos Neutral tonemapping
+// https://github.com/KhronosGroup/ToneMapping/tree/main
+// Input color is non-negative and resides in the Linear Rec. 709 color space.
+// Output color is also Linear Rec. 709, but in the [0, 1] range.
+vec3 PBRNeutralToneMapping( vec3 color )
+{
+  const float startCompression = 0.8 - 0.04;
+  const float desaturation = 0.15;
+
+  float x = min(color.r, min(color.g, color.b));
+  float offset = x < 0.08 ? x - 6.25 * x * x : 0.04;
+  color -= offset;
+
+  float peak = max(color.r, max(color.g, color.b));
+  if (peak < startCompression) return color;
+
+  const float d = 1. - startCompression;
+  float newPeak = 1. - d * d / (peak + d - startCompression);
+  color *= newPeak / peak;
+
+  float g = 1. - 1. / (desaturation * (peak - newPeak) + 1.);
+  return mix(color, newPeak * vec3(1, 1, 1), g);
+}
+
+uniform float exposure;
+uniform float tonemap_mix;
+uniform int tonemap_type;
+
+vec3 toneMap(vec3 color)
+{
+#ifndef NO_POST
+    float exp_scale = texture(exposureMap, vec2(0.5,0.5)).r;
+
+    color *= exposure * exp_scale;
+
+    vec3 clamped_color = clamp(color.rgb, vec3(0.0), vec3(1.0));
+
+    switch(tonemap_type)
+    {
+    case 0:
+        color = PBRNeutralToneMapping(color);
+        break;
+    case 1:
+        color = toneMapACES_Hill(color);
+        break;
+    }
+
+    // mix tonemapped and linear here to provide adjustment
+    color = mix(clamped_color, color, tonemap_mix);
+#endif
+
+    return color;
+}
+
+
+vec3 toneMapNoExposure(vec3 color)
+{
+#ifndef NO_POST
+    vec3 clamped_color = clamp(color.rgb, vec3(0.0), vec3(1.0));
+
+    switch(tonemap_type)
+    {
+    case 0:
+        color = PBRNeutralToneMapping(color);
+        break;
+    case 1:
+        color = toneMapACES_Hill(color);
+        break;
+    }
+
+    // mix tonemapped and linear here to provide adjustment
+    color = mix(clamped_color, color, tonemap_mix);
+#endif
+
+    return color;
+}
+
+
+//===============================================================
+
+void debugExposure(inout vec3 color)
+{
+    float exp_scale = texture(exposureMap, vec2(0.5,0.5)).r;
+    exp_scale *= 0.5;
+    if (abs(vary_fragcoord.y-exp_scale) < 0.01 && vary_fragcoord.x < 0.1)
+    {
+        color = vec3(1,0,0);
+    }
+}
diff --git a/indra/newview/app_settings/shaders/class3/environment/waterF.glsl b/indra/newview/app_settings/shaders/class3/environment/waterF.glsl
index 7027e3796e..c56e38d016 100644
--- a/indra/newview/app_settings/shaders/class3/environment/waterF.glsl
+++ b/indra/newview/app_settings/shaders/class3/environment/waterF.glsl
@@ -90,21 +90,15 @@ uniform sampler2D depthMap;
 
 uniform sampler2D exclusionTex;
 
-uniform float sunAngle;
-uniform float sunAngle2;
+uniform int classic_mode;
 uniform vec3 lightDir;
 uniform vec3 specular;
-uniform float lightExp;
+uniform float blurMultiplier;
 uniform float refScale;
 uniform float kd;
-uniform vec2 screenRes;
 uniform vec3 normScale;
 uniform float fresnelScale;
 uniform float fresnelOffset;
-uniform float blurMultiplier;
-uniform vec4 waterFogColor;
-uniform vec3 waterFogColorLinear;
-
 
 //bigWave is (refCoord.w, view.w);
 in vec4 refCoord;
@@ -126,6 +120,7 @@ vec3 linear_to_srgb(vec3 col);
 
 vec3 atmosLighting(vec3 light);
 vec3 scaleSoftClip(vec3 light);
+vec3 toneMapNoExposure(vec3 color);
 
 vec3 vN, vT, vB;
 
@@ -171,18 +166,18 @@ void calculateFresnelFactors(out vec3 df3, out vec2 df2, vec3 viewVec, vec3 wave
     // We calculate the fresnel here.
     // We do this by getting the dot product for each sets of waves, and applying scale and offset.
 
-    df3 = vec3(
+    df3 = max(vec3(0), vec3(
         dot(viewVec, wave1),
         dot(viewVec, (wave2 + wave3) * 0.5),
         dot(viewVec, wave3)
-    ) * fresnelScale + fresnelOffset;
+    ) * fresnelScale + fresnelOffset);
 
     df3 *= df3;
 
-    df2 = vec2(
+    df2 = max(vec2(0), vec2(
         df3.x + df3.y + df3.z,
         dot(viewVec, wavef) * fresnelScale + fresnelOffset
-    );
+    ));
 }
 
 void main()
@@ -194,6 +189,7 @@ void main()
     vB = cross(vN, vT);
 
     vec3 pos = vary_position.xyz;
+    float linear_depth = 1 / -pos.z;
 
     float dist = length(pos.xyz);
 
@@ -216,6 +212,12 @@ void main()
     vec3 df3 = vec3(0);
     vec2 df2 = vec2(0);
 
+    vec3 sunlit;
+    vec3 amblit;
+    vec3 additive;
+    vec3 atten;
+    calcAtmosphericVarsLinear(pos.xyz, wavef, vary_light_dir, sunlit, amblit, additive, atten);
+
     calculateFresnelFactors(df3, df2, normalize(view.xyz), wave1, wave2, wave3, wavef);
 
     vec3 waver = wavef*3;
@@ -230,7 +232,7 @@ void main()
     vec3 norm = transform_normal(normalize(wavef));
 
     vdu = clamp(vdu, 0, 1);
-    wavef.z *= max(vdu*vdu*vdu, 0.1);
+    //wavef.z *= max(vdu*vdu*vdu, 0.1);
 
     wavef = normalize(wavef);
 
@@ -245,11 +247,6 @@ void main()
 
     distort2 = clamp(distort2, vec2(0), vec2(0.999));
 
-    vec3 sunlit;
-    vec3 amblit;
-    vec3 additive;
-    vec3 atten;
-
     float shadow = 1.0f;
 
     float water_mask = texture(exclusionTex, distort).r;
@@ -258,8 +255,6 @@ void main()
     shadow = sampleDirectionalShadow(pos.xyz, norm.xyz, distort);
 #endif
 
-    calcAtmosphericVarsLinear(pos.xyz, wavef, vary_light_dir, sunlit, amblit, additive, atten);
-
     vec3 sunlit_linear = srgb_to_linear(sunlit);
     float fade = 0;
 #ifdef TRANSPARENT_WATER
@@ -289,8 +284,8 @@ void main()
 #endif
 
     float metallic = 1.0;
-    float perceptualRoughness = 0.1;
-    float gloss      = 0.95;
+    float perceptualRoughness = blurMultiplier;
+    float gloss      = 1 - perceptualRoughness;
 
     vec3  irradiance = vec3(0);
     vec3  radiance  = vec3(0);
@@ -300,7 +295,7 @@ void main()
 #ifdef WATER_MINIMAL
     sampleReflectionProbesWater(irradiance, radiance, distort2, pos.xyz, wave_ibl.xyz, gloss, amblit);
 #elif WATER_MINIMAL_PLUS
-    sampleReflectionProbes(irradiance, radiance, distort2, pos.xyz, wave_ibl.xyz, 1, false, amblit);
+    sampleReflectionProbes(irradiance, radiance, distort2, pos.xyz, wave_ibl.xyz, gloss, false, amblit);
 #endif
 
     vec3 diffuseColor = vec3(0);
@@ -323,20 +318,26 @@ void main()
     pbrPunctual(diffuseColor, specularColor, perceptualRoughness, metallic, normalize(wavef+up*max(dist, 32.0)/32.0*(1.0-vdu)), v, normalize(light_dir), nl, diffPunc, specPunc);
 
     vec3 punctual = clamp(nl * (diffPunc + specPunc), vec3(0), vec3(10)) * sunlit_linear * shadow;
-
+    radiance *= df2.y;
+    //radiance = toneMapNoExposure(radiance);
     vec3 color = vec3(0);
-    color = mix(fb.rgb, radiance * df2.y, df2.x * 0.99999) + punctual.rgb;
+    color = mix(fb.rgb, radiance, min(1, df2.x)) + punctual.rgb;
+
+    float water_haze_scale = 4;
+
+    if (classic_mode > 0)
+        water_haze_scale = 1;
 
     // This looks super janky, but we do this to restore water haze in the distance.
     // These values were finagled in to try and bring back some of the distant brightening on legacy water.  Also works reasonably well on PBR skies such as PBR midday.
-    color += color * min(vec3(4),pow(1 - atten, vec3(1.35)) * 16 * fade);
+    // color = mix(color, additive * water_haze_scale, (1 - atten));
 
     // We shorten the fade here at the shoreline so it doesn't appear too soft from a distance.
     fade *= 60;
     fade = min(1, fade);
     color = mix(fb.rgb, color, fade);
 
-    float spec = min(max(max(punctual.r, punctual.g), punctual.b), 0.05);
+    float spec = min(max(max(punctual.r, punctual.g), punctual.b), 0);
 
     frag_color = min(vec4(1),max(vec4(color.rgb, spec * water_mask), vec4(0)));
 }
diff --git a/indra/newview/lldrawpoolwater.cpp b/indra/newview/lldrawpoolwater.cpp
index c27f5ef486..32de0e5ee7 100644
--- a/indra/newview/lldrawpoolwater.cpp
+++ b/indra/newview/lldrawpoolwater.cpp
@@ -176,154 +176,133 @@ void LLDrawPoolWater::renderPostDeferred(S32 pass)
         light_diffuse *= (1.5f + (6.f * ground_proj_sq));
     }
 
-    // set up normal maps filtering
-    for (auto norm_map : mWaterNormp)
-        {
-        if (norm_map) norm_map->setFilteringOption(has_normal_mips ? LLTexUnit::TFO_ANISOTROPIC : LLTexUnit::TFO_POINT);
-        }
+    LLTexUnit::eTextureFilterOptions filter_mode = has_normal_mips ? LLTexUnit::TFO_ANISOTROPIC : LLTexUnit::TFO_POINT;
 
     LLColor4      specular(sun_up ? psky->getSunlightColor() : psky->getMoonlightColor());
     F32           phase_time = (F32) LLFrameTimer::getElapsedSeconds() * 0.5f;
     LLGLSLShader *shader     = nullptr;
 
-    // two passes, first with standard water shader bound, second with edge water shader bound
-    for (int edge = 0; edge < 2; edge++)
+    // One pass, one of two shaders.  Void water and region water share state.
+    // There isn't a good reason anymore to really have void water run in a separate pass.
+    // It also just introduced a bunch of weird state consistency stuff that we really don't need.
+    // Not to mention, re-binding the the same shader and state for that shader is kind of wasteful.
+    // - Geenz 2025-02-11
+    // select shader
+    if (underwater)
     {
-        // select shader
-        if (underwater)
-        {
-            shader = &gUnderWaterProgram;
-        }
-        else
-        {
-            if (edge)
-            {
-                shader = &gWaterEdgeProgram;
-            }
-            else
-            {
-                shader = &gWaterProgram;
-            }
-        }
-
-        gPipeline.bindDeferredShader(*shader, nullptr, &gPipeline.mWaterDis);
-
-        //bind normal map
-        S32 bumpTex = shader->enableTexture(LLViewerShaderMgr::BUMP_MAP);
-        S32 bumpTex2 = shader->enableTexture(LLViewerShaderMgr::BUMP_MAP2);
-
-        LLViewerTexture* tex_a = mWaterNormp[0];
-        LLViewerTexture* tex_b = mWaterNormp[1];
+        shader = &gUnderWaterProgram;
+    }
+    else
+    {
+        shader = &gWaterProgram;
+    }
 
-        F32 blend_factor = (F32)pwater->getBlendFactor();
+    gPipeline.bindDeferredShader(*shader, nullptr, &gPipeline.mWaterDis);
 
-        gGL.getTexUnit(bumpTex)->unbind(LLTexUnit::TT_TEXTURE);
-        gGL.getTexUnit(bumpTex2)->unbind(LLTexUnit::TT_TEXTURE);
+    LLViewerTexture* tex_a = mWaterNormp[0];
+    LLViewerTexture* tex_b = mWaterNormp[1];
 
-        if (tex_a && (!tex_b || (tex_a == tex_b)))
-        {
-            gGL.getTexUnit(bumpTex)->bind(tex_a);
-            blend_factor = 0; // only one tex provided, no blending
-        }
-        else if (tex_b && !tex_a)
-        {
-            gGL.getTexUnit(bumpTex)->bind(tex_b);
-            blend_factor = 0; // only one tex provided, no blending
-        }
-        else if (tex_b != tex_a)
-        {
-            gGL.getTexUnit(bumpTex)->bind(tex_a);
-            gGL.getTexUnit(bumpTex2)->bind(tex_b);
-        }
+    F32 blend_factor = (F32)pwater->getBlendFactor();
 
-        shader->bindTexture(LLShaderMgr::WATER_EXCLUSIONTEX, &gPipeline.mWaterExclusionMask);
+    if (tex_a && (!tex_b || (tex_a == tex_b)))
+    {
+        shader->bindTexture(LLViewerShaderMgr::BUMP_MAP, tex_a);
+        tex_a->setFilteringOption(filter_mode);
+        blend_factor = 0; // only one tex provided, no blending
+    }
+    else if (tex_b && !tex_a)
+    {
+        shader->bindTexture(LLViewerShaderMgr::BUMP_MAP, tex_b);
+        tex_a->setFilteringOption(filter_mode);
+        blend_factor = 0; // only one tex provided, no blending
+    }
+    else if (tex_b != tex_a)
+    {
+        shader->bindTexture(LLViewerShaderMgr::BUMP_MAP, tex_a);
+        tex_a->setFilteringOption(filter_mode);
+        shader->bindTexture(LLViewerShaderMgr::BUMP_MAP2, tex_b);
+        tex_b->setFilteringOption(filter_mode);
+    }
 
-        // bind reflection texture from RenderTarget
-        S32 screentex = shader->enableTexture(LLShaderMgr::WATER_SCREENTEX);
+    shader->bindTexture(LLShaderMgr::WATER_EXCLUSIONTEX, &gPipeline.mWaterExclusionMask);
 
-        F32 screenRes[] = { 1.f / gGLViewport[2], 1.f / gGLViewport[3] };
+    shader->uniform1f(LLShaderMgr::BLEND_FACTOR, blend_factor);
 
-        shader->uniform2fv(LLShaderMgr::DEFERRED_SCREEN_RES, 1, screenRes);
-        shader->uniform1f(LLShaderMgr::BLEND_FACTOR, blend_factor);
+    F32      fog_density = pwater->getModifiedWaterFogDensity(underwater);
 
-        F32      fog_density = pwater->getModifiedWaterFogDensity(underwater);
+    shader->bindTexture(LLShaderMgr::WATER_SCREENTEX, &gPipeline.mWaterDis);
 
-        if (screentex > -1)
-        {
-            shader->uniform1f(LLShaderMgr::WATER_FOGDENSITY, fog_density);
-            gGL.getTexUnit(screentex)->bind(&gPipeline.mWaterDis);
-        }
+    if (mShaderLevel == 1)
+    {
+        fog_color.mV[VALPHA] = (F32)(log(fog_density) / log(2));
+    }
 
-        if (mShaderLevel == 1)
-        {
-            fog_color.mV[VALPHA] = (F32)(log(fog_density) / log(2));
-        }
+    F32 water_height = environment.getWaterHeight();
+    F32 camera_height = LLViewerCamera::getInstance()->getOrigin().mV[2];
+    shader->uniform1f(LLShaderMgr::WATER_WATERHEIGHT, camera_height - water_height);
+    shader->uniform1f(LLShaderMgr::WATER_TIME, phase_time);
+    shader->uniform3fv(LLShaderMgr::WATER_EYEVEC, 1, LLViewerCamera::getInstance()->getOrigin().mV);
 
-        F32 water_height = environment.getWaterHeight();
-        F32 camera_height = LLViewerCamera::getInstance()->getOrigin().mV[2];
-        shader->uniform1f(LLShaderMgr::WATER_WATERHEIGHT, camera_height - water_height);
-        shader->uniform1f(LLShaderMgr::WATER_TIME, phase_time);
-        shader->uniform3fv(LLShaderMgr::WATER_EYEVEC, 1, LLViewerCamera::getInstance()->getOrigin().mV);
+    shader->uniform3fv(LLShaderMgr::WATER_SPECULAR, 1, light_diffuse.mV);
 
-        shader->uniform4fv(LLShaderMgr::SPECULAR_COLOR, 1, specular.mV);
-        shader->uniform4fv(LLShaderMgr::WATER_FOGCOLOR, 1, fog_color.mV);
-        shader->uniform3fv(LLShaderMgr::WATER_FOGCOLOR_LINEAR, 1, fog_color_linear.mV);
+    shader->uniform2fv(LLShaderMgr::WATER_WAVE_DIR1, 1, pwater->getWave1Dir().mV);
+    shader->uniform2fv(LLShaderMgr::WATER_WAVE_DIR2, 1, pwater->getWave2Dir().mV);
 
-        shader->uniform3fv(LLShaderMgr::WATER_SPECULAR, 1, light_diffuse.mV);
-        shader->uniform1f(LLShaderMgr::WATER_SPECULAR_EXP, light_exp);
+    shader->uniform3fv(LLShaderMgr::WATER_LIGHT_DIR, 1, light_dir.mV);
 
-        shader->uniform2fv(LLShaderMgr::WATER_WAVE_DIR1, 1, pwater->getWave1Dir().mV);
-        shader->uniform2fv(LLShaderMgr::WATER_WAVE_DIR2, 1, pwater->getWave2Dir().mV);
+    shader->uniform3fv(LLShaderMgr::WATER_NORM_SCALE, 1, pwater->getNormalScale().mV);
+    shader->uniform1f(LLShaderMgr::WATER_FRESNEL_SCALE, pwater->getFresnelScale());
+    shader->uniform1f(LLShaderMgr::WATER_FRESNEL_OFFSET, pwater->getFresnelOffset());
+    shader->uniform1f(LLShaderMgr::WATER_BLUR_MULTIPLIER, fmaxf(0, pwater->getBlurMultiplier()) * 2);
 
-        shader->uniform3fv(LLShaderMgr::WATER_LIGHT_DIR, 1, light_dir.mV);
+    static LLStaticHashedString s_exposure("exposure");
+    static LLStaticHashedString tonemap_mix("tonemap_mix");
+    static LLStaticHashedString tonemap_type("tonemap_type");
 
-        shader->uniform3fv(LLShaderMgr::WATER_NORM_SCALE, 1, pwater->getNormalScale().mV);
-        shader->uniform1f(LLShaderMgr::WATER_FRESNEL_SCALE, pwater->getFresnelScale());
-        shader->uniform1f(LLShaderMgr::WATER_FRESNEL_OFFSET, pwater->getFresnelOffset());
-        shader->uniform1f(LLShaderMgr::WATER_BLUR_MULTIPLIER, pwater->getBlurMultiplier());
+    static LLCachedControl<F32> exposure(gSavedSettings, "RenderExposure", 1.f);
 
-        F32 sunAngle = llmax(0.f, light_dir.mV[1]);
-        F32 scaledAngle = 1.f - sunAngle;
+    F32 e = llclamp(exposure(), 0.5f, 4.f);
 
-        shader->uniform1i(LLShaderMgr::SUN_UP_FACTOR, sun_up ? 1 : 0);
-        shader->uniform1f(LLShaderMgr::WATER_SUN_ANGLE, sunAngle);
-        shader->uniform1f(LLShaderMgr::WATER_SCALED_ANGLE, scaledAngle);
-        shader->uniform1f(LLShaderMgr::WATER_SUN_ANGLE2, 0.1f + 0.2f * sunAngle);
-        shader->uniform1i(LLShaderMgr::WATER_EDGE_FACTOR, edge ? 1 : 0);
+    static LLCachedControl<bool> should_auto_adjust(gSavedSettings, "RenderSkyAutoAdjustLegacy", false);
 
-        // SL-15861 This was changed from getRotatedLightNorm() as it was causing
-        // lightnorm in shaders\class1\windlight\atmosphericsFuncs.glsl in have inconsistent additive lighting for 180 degrees of the FOV.
-        LLVector4 rotated_light_direction = LLEnvironment::instance().getClampedLightNorm();
-        shader->uniform3fv(LLViewerShaderMgr::LIGHTNORM, 1, rotated_light_direction.mV);
+    shader->uniform1f(s_exposure, e);
+    static LLCachedControl<U32> tonemap_type_setting(gSavedSettings, "RenderTonemapType", 0U);
+    shader->uniform1i(tonemap_type, tonemap_type_setting);
+    shader->uniform1f(tonemap_mix, psky->getTonemapMix(should_auto_adjust()));
 
-        shader->uniform3fv(LLShaderMgr::WL_CAMPOSLOCAL, 1, LLViewerCamera::getInstance()->getOrigin().mV);
+    F32 sunAngle = llmax(0.f, light_dir.mV[1]);
+    F32 scaledAngle = 1.f - sunAngle;
 
-        if (LLViewerCamera::getInstance()->cameraUnderWater())
-        {
-            shader->uniform1f(LLShaderMgr::WATER_REFSCALE, pwater->getScaleBelow());
-        }
-        else
-        {
-            shader->uniform1f(LLShaderMgr::WATER_REFSCALE, pwater->getScaleAbove());
-        }
+    shader->uniform1i(LLShaderMgr::SUN_UP_FACTOR, sun_up ? 1 : 0);
 
-        LLGLDisable cullface(GL_CULL_FACE);
+    // SL-15861 This was changed from getRotatedLightNorm() as it was causing
+    // lightnorm in shaders\class1\windlight\atmosphericsFuncs.glsl in have inconsistent additive lighting for 180 degrees of the FOV.
+    LLVector4 rotated_light_direction = LLEnvironment::instance().getClampedLightNorm();
+    shader->uniform3fv(LLViewerShaderMgr::LIGHTNORM, 1, rotated_light_direction.mV);
 
-        pushWaterPlanes(edge);
+    shader->uniform3fv(LLShaderMgr::WL_CAMPOSLOCAL, 1, LLViewerCamera::getInstance()->getOrigin().mV);
 
-        shader->disableTexture(LLShaderMgr::ENVIRONMENT_MAP, LLTexUnit::TT_CUBE_MAP);
-        shader->disableTexture(LLShaderMgr::WATER_SCREENTEX);
-        shader->disableTexture(LLShaderMgr::BUMP_MAP);
+    if (LLViewerCamera::getInstance()->cameraUnderWater())
+    {
+        shader->uniform1f(LLShaderMgr::WATER_REFSCALE, pwater->getScaleBelow());
+    }
+    else
+    {
+        shader->uniform1f(LLShaderMgr::WATER_REFSCALE, pwater->getScaleAbove());
+    }
 
-        // clean up
-        gPipeline.unbindDeferredShader(*shader);
+    LLGLDisable cullface(GL_CULL_FACE);
 
-        gGL.getTexUnit(bumpTex)->unbind(LLTexUnit::TT_TEXTURE);
-        gGL.getTexUnit(bumpTex2)->unbind(LLTexUnit::TT_TEXTURE);
-    }
+    // Only push the water planes once.
+    // Previously we did this twice: once for void water and one for region water.
+    // However, the void water and region water shaders are the same exact shader.
+    // They also had the same exact state with the sole exception setting an edge water flag.
+    // That flag was not actually used anywhere in the shaders.
+    // - Geenz 2025-02-11
+    pushWaterPlanes(0);
 
-    gGL.getTexUnit(0)->activate();
-    gGL.getTexUnit(0)->enable(LLTexUnit::TT_TEXTURE);
+    // clean up
+    gPipeline.unbindDeferredShader(*shader);
 
     gGL.setColorMask(true, false);
 }
@@ -333,22 +312,18 @@ void LLDrawPoolWater::pushWaterPlanes(int pass)
     LLVOWater* water = nullptr;
     for (LLFace* const& face : mDrawFace)
     {
-        if (!face)
-            continue;
         water = static_cast<LLVOWater*>(face->getViewerObject());
-        if (!water)
-            continue;
 
-        if ((bool)pass == (bool)water->getIsEdgePatch())
+        face->renderIndexed();
+
+        // Note non-void water being drawn, updates required
+        // Previously we had some logic to determine if this pass was also our water edge pass.
+        // Now we only have one pass.  Check if we're doing a region water plane or void water plane.
+        // - Geenz 2025-02-11
+        if (!water->getIsEdgePatch())
         {
-            face->renderIndexed();
-
-            // Note non-void water being drawn, updates required
-            if (!pass) // SL-16461 remove !LLPipeline::sUseOcclusion check
-            {
-                sNeedsReflectionUpdate = true;
-                sNeedsDistortionUpdate = true;
-            }
+            sNeedsReflectionUpdate = true;
+            sNeedsDistortionUpdate = true;
         }
     }
 }
diff --git a/indra/newview/llviewershadermgr.cpp b/indra/newview/llviewershadermgr.cpp
index ac4519e593..a0a9906724 100644
--- a/indra/newview/llviewershadermgr.cpp
+++ b/indra/newview/llviewershadermgr.cpp
@@ -114,7 +114,6 @@ LLGLSLShader        gObjectAlphaMaskNoColorProgram;
 
 //environment shaders
 LLGLSLShader        gWaterProgram;
-LLGLSLShader        gWaterEdgeProgram;
 LLGLSLShader        gUnderWaterProgram;
 
 //interface shaders
@@ -410,7 +409,6 @@ void LLViewerShaderMgr::finalizeShaderList()
     //ONLY shaders that need WL Param management should be added here
     mShaderList.push_back(&gAvatarProgram);
     mShaderList.push_back(&gWaterProgram);
-    mShaderList.push_back(&gWaterEdgeProgram);
     mShaderList.push_back(&gAvatarEyeballProgram);
     mShaderList.push_back(&gImpostorProgram);
     mShaderList.push_back(&gObjectBumpProgram);
@@ -877,6 +875,7 @@ std::string LLViewerShaderMgr::loadBasicShaders()
     index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/shadowUtil.glsl",                      1) );
     index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/aoUtil.glsl",                          1) );
     index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/pbrterrainUtilF.glsl",                 1) );
+    index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/tonemapUtilF.glsl",                    1) );
     index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/reflectionProbeF.glsl",                has_reflection_probes ? 3 : 2) );
     index_channels.push_back(-1);    shaders.push_back( make_pair( "deferred/screenSpaceReflUtil.glsl",             ssr ? 3 : 1) );
     index_channels.push_back(-1);    shaders.push_back( make_pair( "lighting/lightNonIndexedF.glsl",                    mShaderLevel[SHADER_LIGHTING] ) );
@@ -909,7 +908,6 @@ bool LLViewerShaderMgr::loadShadersWater()
     if (mShaderLevel[SHADER_WATER] == 0)
     {
         gWaterProgram.unload();
-        gWaterEdgeProgram.unload();
         gUnderWaterProgram.unload();
         return true;
     }
@@ -923,6 +921,7 @@ bool LLViewerShaderMgr::loadShadersWater()
         gWaterProgram.mFeatures.hasGamma = true;
         gWaterProgram.mFeatures.hasSrgb = true;
         gWaterProgram.mFeatures.hasReflectionProbes = true;
+        gWaterProgram.mFeatures.hasTonemap = true;
         gWaterProgram.mFeatures.hasShadows = use_sun_shadow;
         gWaterProgram.mShaderFiles.clear();
         gWaterProgram.mShaderFiles.push_back(make_pair("environment/waterV.glsl", GL_VERTEX_SHADER));
@@ -946,36 +945,6 @@ bool LLViewerShaderMgr::loadShadersWater()
 
     if (success)
     {
-    // load water shader
-        gWaterEdgeProgram.mName = "Water Edge Shader";
-        gWaterEdgeProgram.mFeatures.calculatesAtmospherics = true;
-        gWaterEdgeProgram.mFeatures.hasAtmospherics = true;
-        gWaterEdgeProgram.mFeatures.hasGamma = true;
-        gWaterEdgeProgram.mFeatures.hasSrgb = true;
-        gWaterEdgeProgram.mFeatures.hasReflectionProbes = true;
-        gWaterEdgeProgram.mFeatures.hasShadows = use_sun_shadow;
-        gWaterEdgeProgram.mShaderFiles.clear();
-        gWaterEdgeProgram.mShaderFiles.push_back(make_pair("environment/waterV.glsl", GL_VERTEX_SHADER));
-        gWaterEdgeProgram.mShaderFiles.push_back(make_pair("environment/waterF.glsl", GL_FRAGMENT_SHADER));
-        gWaterEdgeProgram.clearPermutations();
-        gWaterEdgeProgram.addPermutation("WATER_EDGE", "1");
-        if (LLPipeline::sRenderTransparentWater)
-        {
-            gWaterEdgeProgram.addPermutation("TRANSPARENT_WATER", "1");
-        }
-
-        if (use_sun_shadow)
-        {
-            gWaterEdgeProgram.addPermutation("HAS_SUN_SHADOW", "1");
-        }
-        gWaterEdgeProgram.mShaderGroup = LLGLSLShader::SG_WATER;
-        gWaterEdgeProgram.mShaderLevel = mShaderLevel[SHADER_WATER];
-        success = gWaterEdgeProgram.createShader();
-        llassert(success);
-    }
-
-    if (success)
-    {
         //load under water vertex shader
         gUnderWaterProgram.mName = "Underwater Shader";
         gUnderWaterProgram.mFeatures.calculatesAtmospherics = true;
@@ -2484,6 +2453,7 @@ bool LLViewerShaderMgr::loadShadersDeferred()
         gDeferredPostTonemapProgram.mName = "Deferred Tonemap Post Process";
         gDeferredPostTonemapProgram.mFeatures.hasSrgb = true;
         gDeferredPostTonemapProgram.mFeatures.isDeferred = true;
+        gDeferredPostTonemapProgram.mFeatures.hasTonemap = true;
         gDeferredPostTonemapProgram.mShaderFiles.clear();
         gDeferredPostTonemapProgram.clearPermutations();
         gDeferredPostTonemapProgram.mShaderFiles.push_back(make_pair("deferred/postDeferredNoTCV.glsl", GL_VERTEX_SHADER));
@@ -2498,6 +2468,7 @@ bool LLViewerShaderMgr::loadShadersDeferred()
         gNoPostTonemapProgram.mName = "No Post Tonemap Post Process";
         gNoPostTonemapProgram.mFeatures.hasSrgb = true;
         gNoPostTonemapProgram.mFeatures.isDeferred = true;
+        gNoPostTonemapProgram.mFeatures.hasTonemap = true;
         gNoPostTonemapProgram.mShaderFiles.clear();
         gNoPostTonemapProgram.clearPermutations();
         gNoPostTonemapProgram.addPermutation("NO_POST", "1");
diff --git a/indra/newview/llviewershadermgr.h b/indra/newview/llviewershadermgr.h
index 6326de9a6b..7ad2da9464 100644
--- a/indra/newview/llviewershadermgr.h
+++ b/indra/newview/llviewershadermgr.h
@@ -192,7 +192,6 @@ extern LLGLSLShader     gObjectAlphaMaskNoColorProgram;
 
 //environment shaders
 extern LLGLSLShader         gWaterProgram;
-extern LLGLSLShader         gWaterEdgeProgram;
 extern LLGLSLShader         gUnderWaterProgram;
 extern LLGLSLShader         gGlowProgram;
 extern LLGLSLShader         gGlowExtractProgram;