From e790bfb7e8ed309a0f1a490b4fd4a74e05db5ca7 Mon Sep 17 00:00:00 2001
From: James Seibel <jeseibel@gondtc.com>
Date: Sat, 7 Mar 2026 14:32:02 -0600
Subject: [PATCH] merge apply shaders

---
 .../assets/distanthorizons/shaders/apply/frag.fsh    | 10 ++++------
 .../assets/distanthorizons/shaders/apply/vert.vsh    |  5 ++++-
 .../assets/distanthorizons/shaders/ssao/apply.fsh    | 12 ++++++------
 3 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/core/src/main/resources/assets/distanthorizons/shaders/apply/frag.fsh b/core/src/main/resources/assets/distanthorizons/shaders/apply/frag.fsh
index c5a5d3635..2b0745aec 100644
--- a/core/src/main/resources/assets/distanthorizons/shaders/apply/frag.fsh
+++ b/core/src/main/resources/assets/distanthorizons/shaders/apply/frag.fsh
@@ -4,22 +4,20 @@ in vec2 TexCoord;
 
 out vec4 fragColor;
 
-uniform sampler2D uDhColorTexture;
-uniform sampler2D uDhDepthTexture;
+uniform sampler2D uSourceColorTexture;
+uniform sampler2D uSourceDepthTexture;
 
 // DH apply frag
 void main()
 {
-    //fragColor = texture(uApplyTexture, TexCoord);
-
     fragColor = vec4(0.0);
 
     // a fragment depth of "1" means the fragment wasn't drawn to,
     // only update fragments that were drawn to
-    float fragmentDepth = texture(uDhDepthTexture, TexCoord).r;
+    float fragmentDepth = texture(uSourceDepthTexture, TexCoord).r;
     if (fragmentDepth != 1)
     {
-        fragColor = texture(uDhColorTexture, TexCoord);
+        fragColor = texture(uSourceColorTexture, TexCoord);
     }
     else
     {
diff --git a/core/src/main/resources/assets/distanthorizons/shaders/apply/vert.vsh b/core/src/main/resources/assets/distanthorizons/shaders/apply/vert.vsh
index 09789a24b..f58a25234 100644
--- a/core/src/main/resources/assets/distanthorizons/shaders/apply/vert.vsh
+++ b/core/src/main/resources/assets/distanthorizons/shaders/apply/vert.vsh
@@ -4,7 +4,10 @@ in vec2 vPosition;
 
 out vec2 TexCoord;
 
-// DH apply
+/** 
+ * This is specifically used by application shaders.
+ * IE post process or pixel transfer shaders, anything that is rendered using a single rectangle.
+ */
 void main()
 {
     gl_Position = vec4(vPosition, 0.0, 1.0);
diff --git a/core/src/main/resources/assets/distanthorizons/shaders/ssao/apply.fsh b/core/src/main/resources/assets/distanthorizons/shaders/ssao/apply.fsh
index dc48356f3..00a404cda 100644
--- a/core/src/main/resources/assets/distanthorizons/shaders/ssao/apply.fsh
+++ b/core/src/main/resources/assets/distanthorizons/shaders/ssao/apply.fsh
@@ -4,8 +4,8 @@ in vec2 TexCoord;
 
 out vec4 fragColor;
 
-uniform sampler2D uSsaoColorTexture;
-uniform sampler2D uDhDepthTexture;
+uniform sampler2D uSourceColorTexture;
+uniform sampler2D uSourceDepthTexture;
 
 uniform vec2 gViewSize;
 uniform int gBlurRadius;
@@ -38,8 +38,8 @@ float BilateralGaussianBlur(const in vec2 texcoord, const in float linearDepth,
             float fx = Gaussian(g_sigmaX, ix);
 
             vec2 sampleTex = texcoord + ivec2(ix, iy) * pixelSize;
-            float sampleValue = textureLod(uSsaoColorTexture, sampleTex, 0).r;
-            float sampleDepth = textureLod(uDhDepthTexture, sampleTex, 0).r;
+            float sampleValue = textureLod(uSourceColorTexture, sampleTex, 0).r;
+            float sampleDepth = textureLod(uSourceDepthTexture, sampleTex, 0).r;
             float sampleLinearDepth = linearizeDepth(sampleDepth);
 
             float depthDiff = abs(sampleLinearDepth - linearDepth);
@@ -60,7 +60,7 @@ void main()
 {
     fragColor = vec4(1.0);
     
-    float fragmentDepth = textureLod(uDhDepthTexture, TexCoord, 0).r;
+    float fragmentDepth = textureLod(uSourceDepthTexture, TexCoord, 0).r;
 
     // a fragment depth of "1" means the fragment wasn't drawn to,
     // we only want to apply SSAO to LODs, not to the sky outside the LODs
@@ -73,7 +73,7 @@ void main()
         }
         else 
         {
-            fragColor.a = texelFetch(uSsaoColorTexture, ivec2(gl_FragCoord.xy), 0).r;
+            fragColor.a = texelFetch(uSourceColorTexture, ivec2(gl_FragCoord.xy), 0).r;
         }
     }
 }