Gloom: Fetching material texture colors in shaders

doomsday/tests/test_gloom/gloom/render/context.h

@@ -47,10 +47,10 @@ struct Context {
 
     de::GLUniform uCurrentTime      {"uCurrentTime",      de::GLUniform::Float};
 
-    de::GLUniform uDiffuseAtlas     {"uDiffuseAtlas",     de::GLUniform::Sampler2D};
-    de::GLUniform uEmissiveAtlas    {"uEmissiveAtlas",    de::GLUniform::Sampler2D};
-    de::GLUniform uSpecGlossAtlas   {"uSpecGlossAtlas",   de::GLUniform::Sampler2D};
-    de::GLUniform uNormalDisplAtlas {"uNormalDisplAtlas", de::GLUniform::Sampler2D};
+    de::GLUniform uDiffuseAtlas     {"uTextureAtlas[0]",  de::GLUniform::Sampler2D};
+    de::GLUniform uSpecGlossAtlas   {"uTextureAtlas[1]",  de::GLUniform::Sampler2D};
+    de::GLUniform uEmissiveAtlas    {"uTextureAtlas[2]",  de::GLUniform::Sampler2D};
+    de::GLUniform uNormalDisplAtlas {"uTextureAtlas[3]",  de::GLUniform::Sampler2D};
 
     de::GLUniform uLightMatrix      {"uLightMatrix",      de::GLUniform::Mat4};
     de::GLUniform uLightOrigin      {"uLightOrigin",      de::GLUniform::Vec3};

doomsday/tests/test_gloom/net.dengine.gloom.pack/shaders/common/material.glsl

@@ -0,0 +1,36 @@
+#ifndef GLOOM_MATERIAL_H
+#define GLOOM_MATERIAL_H
+
+#include "defs.glsl"
+#include "miplevel.glsl"
+
+uniform sampler2D uTextureAtlas[4];
+uniform sampler2D uTextureMetrics;
+
+struct Metrics {
+    vec4  uvRect;
+    vec2  sizeInTexels;
+    float texelsPerMeter;
+    vec2  scale;
+};
+
+Metrics Gloom_TextureMetrics(uint matIndex, int texture) {
+    Metrics metrics;
+    int x = texture * 2;
+    metrics.uvRect = texelFetch(uTextureMetrics, ivec2(x, matIndex), 0);
+    vec3 texelSize = texelFetch(uTextureMetrics, ivec2(x + 1, matIndex), 0).xyz;
+    metrics.sizeInTexels   = texelSize.xy;
+    metrics.texelsPerMeter = texelSize.z;
+    metrics.scale          = vec2(metrics.texelsPerMeter) / metrics.sizeInTexels;
+    return metrics;
+}
+
+vec4 Gloom_FetchTexture(uint matIndex, int texture, vec2 uv) {
+    Metrics metrics = Gloom_TextureMetrics(matIndex, texture);
+    vec2 normUV  = uv * metrics.scale;
+    vec2 atlasUV = metrics.uvRect.xy + fract(normUV) * metrics.uvRect.zw;
+    return textureLod(uTextureAtlas[texture], atlasUV,
+                      mipLevel(normUV, metrics.sizeInTexels.xy) - 0.5);
+}
+
+#endif // GLOOM_MATERIAL_H

doomsday/tests/test_gloom/net.dengine.gloom.pack/shaders/entity_material.fsh

@@ -1,15 +1,14 @@
 #version 330 core
 
 #include "common/gbuffer_out.glsl"
-
-uniform sampler2D uDiffuseAtlas;
+#include "common/material.glsl"
 
 DENG_VAR vec2 vUV;
 DENG_VAR vec4 vInstanceColor;
 DENG_VAR vec3 vNormal;
 
 void main(void) {
-    vec4 color = texture(uDiffuseAtlas, vUV);
+    vec4 color = texture(uTextureAtlas[Texture_Diffuse], vUV);
     if (color.a < 0.5) discard;
     out_FragColor = color * vInstanceColor;
     GBuffer_SetFragNormal(vNormal);

doomsday/tests/test_gloom/net.dengine.gloom.pack/shaders/entity_shadow_dir.fsh

@@ -1,10 +1,10 @@
 #version 330 core
 
-uniform sampler2D uDiffuseAtlas;
+#include "common/material.glsl"
 
 DENG_VAR vec2 vUV;
 
 void main(void) {
-    float alpha = texture(uDiffuseAtlas, vUV).a;
+    float alpha = texture(uTextureAtlas[Texture_Diffuse], vUV).a;
     if (alpha < 0.75) discard;
 }

doomsday/tests/test_gloom/net.dengine.gloom.pack/shaders/entity_shadow_omni.fsh

@@ -1,6 +1,6 @@
 #version 330 core
 
-uniform sampler2D uDiffuseAtlas;
+#include "common/material.glsl"
 
 uniform vec3  uLightOrigin; // world space
 uniform float uFarPlane;
@@ -9,7 +9,7 @@ in vec4 vWorldPos;
 in vec2 vFaceUV;
 
 void main(void) {
-    float alpha = texture(uDiffuseAtlas, vFaceUV).a;
+    float alpha = texture(uTextureAtlas[Texture_Diffuse], vFaceUV).a;
     if (alpha < 0.75) discard;
 
     // Normalized distance.

doomsday/tests/test_gloom/net.dengine.gloom.pack/shaders/surface_material.fsh

@@ -1,10 +1,7 @@
 #version 330 core
 
 #include "common/gbuffer_out.glsl"
-#include "common/miplevel.glsl"
-
-uniform sampler2D uDiffuseAtlas;
-uniform sampler2D uTextureMetrics;
+#include "common/material.glsl"
 
      DENG_VAR vec2  vUV;
      DENG_VAR vec3  vNormal;
@@ -14,18 +11,9 @@ flat DENG_VAR uint  vFlags;
 void main(void) {
     uint matIndex = uint(vMaterial + 0.5);
 
-    // Albedo color.
-    vec4  uvRect         = texelFetch(uTextureMetrics, ivec2(0, matIndex), 0);
-    vec3  texelSize      = texelFetch(uTextureMetrics, ivec2(1, matIndex), 0).xyz;
-    float texelsPerMeter = texelSize.z;
-    vec2  texScale       = vec2(texelsPerMeter) / texelSize.xy;
-
-    vec2 normUV = vUV * texScale;
-    vec2 uv = uvRect.xy + fract(normUV) * uvRect.zw;
-
-    vec4 color = textureLod(uDiffuseAtlas, uv, mipLevel(normUV, texelSize.xy) - 0.5);
-    if (color.a < 0.005)
-    {
+    // Diffuse color.
+    vec4 color = Gloom_FetchTexture(matIndex, Texture_Diffuse, vUV);
+    if (color.a < 0.005) {
         discard;
     }