From 456816f707c36b482edb7385033bc5d4e282b412 Mon Sep 17 00:00:00 2001
From: scrawl <scrawl@baseoftrash.de>
Date: Wed, 17 Feb 2016 03:07:18 +0100
Subject: [PATCH] Use diffuse.a / vertex.a, use material emission

---
 components/shader/shadervisitor.cpp |  2 +-
 files/shaders/objects_fragment.glsl |  4 ++--
 files/shaders/objects_vertex.glsl   | 29 +++++++++++++++++++----------
 3 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/components/shader/shadervisitor.cpp b/components/shader/shadervisitor.cpp
index 02ece3296..96357ea9d 100644
--- a/components/shader/shadervisitor.cpp
+++ b/components/shader/shadervisitor.cpp
@@ -120,7 +120,7 @@ namespace Shader
             case GL_AMBIENT_AND_DIFFUSE:
                 defineMap["colorMode"] = "2";
                 break;
-            case GL_AMBIENT:
+            case GL_EMISSION:
                 defineMap["colorMode"] = "1";
                 break;
             }
diff --git a/files/shaders/objects_fragment.glsl b/files/shaders/objects_fragment.glsl
index c3f004e02..016cae13f 100644
--- a/files/shaders/objects_fragment.glsl
+++ b/files/shaders/objects_fragment.glsl
@@ -22,7 +22,7 @@ varying vec2 emissiveMapUV;
 
 varying float depth;
 
-varying vec3 lighting;
+varying vec4 lighting;
 
 void main()
 {
@@ -40,7 +40,7 @@ void main()
     gl_FragData[0].xyz *= texture2D(darkMap, darkMapUV).xyz;
 #endif
 
-    gl_FragData[0].xyz *= lighting;
+    gl_FragData[0] *= lighting;
 
 #if @emissiveMap
     gl_FragData[0].xyz += texture2D(emissiveMap, emissiveMapUV).xyz;
diff --git a/files/shaders/objects_vertex.glsl b/files/shaders/objects_vertex.glsl
index 50d6eb490..1805f31de 100644
--- a/files/shaders/objects_vertex.glsl
+++ b/files/shaders/objects_vertex.glsl
@@ -18,24 +18,24 @@ varying vec2 emissiveMapUV;
 
 varying float depth;
 
-varying vec3 lighting;
+varying vec4 lighting;
 
 #define MAX_LIGHTS 8
 
-vec3 doLighting(vec3 viewPos, vec3 viewNormal, vec3 vertexColor)
+vec4 doLighting(vec3 viewPos, vec3 viewNormal, vec4 vertexColor)
 {
     vec3 lightDir;
     float d;
 
 #if @colorMode == 2
-    vec3 diffuse = vertexColor;
-    vec3 ambient = vertexColor;
+    vec4 diffuse = vertexColor;
+    vec3 ambient = vertexColor.xyz;
 #else
-    vec3 diffuse = gl_FrontMaterial.diffuse.xyz;
+    vec4 diffuse = gl_FrontMaterial.diffuse;
     vec3 ambient = gl_FrontMaterial.ambient.xyz;
 #endif
+    vec4 lightResult = vec4(0.0, 0.0, 0.0, diffuse.a);
 
-    vec3 lightResult = vec3(0.0, 0.0, 0.0);
     for (int i=0; i<MAX_LIGHTS; ++i)
     {
         lightDir = gl_LightSource[i].position.xyz - (viewPos.xyz * gl_LightSource[i].position.w);
@@ -43,11 +43,17 @@ vec3 doLighting(vec3 viewPos, vec3 viewNormal, vec3 vertexColor)
         lightDir = normalize(lightDir);
 
         lightResult.xyz += ambient * gl_LightSource[i].ambient.xyz;
-        lightResult.xyz += diffuse * gl_LightSource[i].diffuse.xyz * clamp(1.0 / (gl_LightSource[i].constantAttenuation + gl_LightSource[i].linearAttenuation * d + gl_LightSource[i].quadraticAttenuation * d * d), 0.0, 1.0)
+        lightResult.xyz += diffuse.xyz * gl_LightSource[i].diffuse.xyz * clamp(1.0 / (gl_LightSource[i].constantAttenuation + gl_LightSource[i].linearAttenuation * d + gl_LightSource[i].quadraticAttenuation * d * d), 0.0, 1.0)
                 * max(dot(viewNormal.xyz, lightDir), 0.0);
     }
 
-    lightResult += gl_LightModel.ambient.xyz * ambient;
+    lightResult.xyz += gl_LightModel.ambient.xyz * ambient;
+
+#if @colorMode == 1
+    lightResult.xyz += vertexColor.xyz;
+#else
+    lightResult.xyz += gl_FrontMaterial.emission.xyz;
+#endif
 
     return lightResult;
 }
@@ -78,6 +84,9 @@ void main(void)
     emissiveMapUV = (gl_TextureMatrix[@emissiveMapUV] * gl_MultiTexCoord@emissiveMapUV).xy;
 #endif
 
-    lighting = doLighting(viewPos.xyz, viewNormal, gl_Color.xyz);
-    lighting = clamp(lighting, vec3(0.0, 0.0, 0.0), vec3(1.0, 1.0, 1.0));
+    lighting = doLighting(viewPos.xyz, viewNormal, gl_Color);
+
+    // TODO: make clamp configurable
+    // the following produces fixed-function compatible lighting, w/o clamp arguably looks better
+    //lighting = clamp(lighting, vec4(0.0, 0.0, 0.0, 0.0), vec4(1.0, 1.0, 1.0, 1.0));
 }