Added alpha blending option to terrain lightings to allow alpha stencil textures. (#689)

Updated Terrain materials to allow diffuse textures with alpha

jme3-terrain/src/main/resources/Common/MatDefs/Terrain/SPTerrainLighting.frag

@@ -160,36 +160,60 @@ varying vec2 texCoord;
     #endif
     #ifdef DIFFUSEMAP
         diffuseColor = texture2D(m_DiffuseMap, texCoord * m_DiffuseMap_0_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.r *= diffuseColor.a;
+        #endif
         diffuseColor *= alphaBlend.r;
     #endif
     #ifdef DIFFUSEMAP_1
         vec4 diffuseColor1 = texture2D(m_DiffuseMap_1, texCoord * m_DiffuseMap_1_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.g *= diffuseColor1.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor1, alphaBlend.g );
     #endif
     #ifdef DIFFUSEMAP_2
         vec4 diffuseColor2 = texture2D(m_DiffuseMap_2, texCoord * m_DiffuseMap_2_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.b *= diffuseColor2.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor2, alphaBlend.b );
     #endif
     #ifdef DIFFUSEMAP_3
         vec4 diffuseColor3 = texture2D(m_DiffuseMap_3, texCoord * m_DiffuseMap_3_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.a *= diffuseColor3.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor3, alphaBlend.a );
     #endif
 
     #ifdef ALPHAMAP_1
         #ifdef DIFFUSEMAP_4
             vec4 diffuseColor4 = texture2D(m_DiffuseMap_4, texCoord * m_DiffuseMap_4_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.r *= diffuseColor4.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor4, alphaBlend1.r );
         #endif
         #ifdef DIFFUSEMAP_5
             vec4 diffuseColor5 = texture2D(m_DiffuseMap_5, texCoord * m_DiffuseMap_5_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.g *= diffuseColor5.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor5, alphaBlend1.g );
         #endif
         #ifdef DIFFUSEMAP_6
             vec4 diffuseColor6 = texture2D(m_DiffuseMap_6, texCoord * m_DiffuseMap_6_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.b *= diffuseColor6.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor6, alphaBlend1.b );
         #endif
         #ifdef DIFFUSEMAP_7
             vec4 diffuseColor7 = texture2D(m_DiffuseMap_7, texCoord * m_DiffuseMap_7_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.a *= diffuseColor7.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor7, alphaBlend1.a );
         #endif
     #endif
@@ -197,18 +221,30 @@ varying vec2 texCoord;
     #ifdef ALPHAMAP_2
         #ifdef DIFFUSEMAP_8
             vec4 diffuseColor8 = texture2D(m_DiffuseMap_8, texCoord * m_DiffuseMap_8_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.r *= diffuseColor8.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor8, alphaBlend2.r );
         #endif
         #ifdef DIFFUSEMAP_9
             vec4 diffuseColor9 = texture2D(m_DiffuseMap_9, texCoord * m_DiffuseMap_9_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.g *= diffuseColor9.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor9, alphaBlend2.g );
         #endif
         #ifdef DIFFUSEMAP_10
             vec4 diffuseColor10 = texture2D(m_DiffuseMap_10, texCoord * m_DiffuseMap_10_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.b *= diffuseColor10.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor10, alphaBlend2.b );
         #endif
         #ifdef DIFFUSEMAP_11
             vec4 diffuseColor11 = texture2D(m_DiffuseMap_11, texCoord * m_DiffuseMap_11_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.a *= diffuseColor11.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor11, alphaBlend2.a );
         #endif                   
     #endif
@@ -614,4 +650,4 @@ void main(){
                             SpecularSum.rgb * vec3(light.y);
     }
 
-}
+}

jme3-terrain/src/main/resources/Common/MatDefs/Terrain/TerrainLighting.frag

@@ -161,36 +161,60 @@ varying vec3 lightVec;
     #endif
     #ifdef DIFFUSEMAP
         diffuseColor = texture2D(m_DiffuseMap, texCoord * m_DiffuseMap_0_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.r *= diffuseColor.a;
+        #endif
         diffuseColor *= alphaBlend.r;
     #endif
     #ifdef DIFFUSEMAP_1
         vec4 diffuseColor1 = texture2D(m_DiffuseMap_1, texCoord * m_DiffuseMap_1_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.g *= diffuseColor1.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor1, alphaBlend.g );
     #endif
     #ifdef DIFFUSEMAP_2
         vec4 diffuseColor2 = texture2D(m_DiffuseMap_2, texCoord * m_DiffuseMap_2_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.b *= diffuseColor2.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor2, alphaBlend.b );
     #endif
     #ifdef DIFFUSEMAP_3
         vec4 diffuseColor3 = texture2D(m_DiffuseMap_3, texCoord * m_DiffuseMap_3_scale);
+        #ifdef USE_ALPHA
+          alphaBlend.a *= diffuseColor3.a;
+        #endif
         diffuseColor = mix( diffuseColor, diffuseColor3, alphaBlend.a );
     #endif
 
     #ifdef ALPHAMAP_1
         #ifdef DIFFUSEMAP_4
             vec4 diffuseColor4 = texture2D(m_DiffuseMap_4, texCoord * m_DiffuseMap_4_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.r *= diffuseColor4.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor4, alphaBlend1.r );
         #endif
         #ifdef DIFFUSEMAP_5
             vec4 diffuseColor5 = texture2D(m_DiffuseMap_5, texCoord * m_DiffuseMap_5_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.g *= diffuseColor5.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor5, alphaBlend1.g );
         #endif
         #ifdef DIFFUSEMAP_6
             vec4 diffuseColor6 = texture2D(m_DiffuseMap_6, texCoord * m_DiffuseMap_6_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.b *= diffuseColor6.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor6, alphaBlend1.b );
         #endif
         #ifdef DIFFUSEMAP_7
             vec4 diffuseColor7 = texture2D(m_DiffuseMap_7, texCoord * m_DiffuseMap_7_scale);
+            #ifdef USE_ALPHA
+              alphaBlend1.a *= diffuseColor7.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor7, alphaBlend1.a );
         #endif
     #endif
@@ -198,18 +222,30 @@ varying vec3 lightVec;
     #ifdef ALPHAMAP_2
         #ifdef DIFFUSEMAP_8
             vec4 diffuseColor8 = texture2D(m_DiffuseMap_8, texCoord * m_DiffuseMap_8_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.r *= diffuseColor8.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor8, alphaBlend2.r );
         #endif
         #ifdef DIFFUSEMAP_9
             vec4 diffuseColor9 = texture2D(m_DiffuseMap_9, texCoord * m_DiffuseMap_9_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.g *= diffuseColor9.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor9, alphaBlend2.g );
         #endif
         #ifdef DIFFUSEMAP_10
             vec4 diffuseColor10 = texture2D(m_DiffuseMap_10, texCoord * m_DiffuseMap_10_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.b *= diffuseColor10.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor10, alphaBlend2.b );
         #endif
         #ifdef DIFFUSEMAP_11
             vec4 diffuseColor11 = texture2D(m_DiffuseMap_11, texCoord * m_DiffuseMap_11_scale);
+            #ifdef USE_ALPHA
+              alphaBlend2.a *= diffuseColor11.a;
+            #endif
             diffuseColor = mix( diffuseColor, diffuseColor11, alphaBlend2.a );
         #endif                   
     #endif
@@ -616,4 +652,4 @@ void main(){
                     SpecularSum * specularColor * light.y;
 
     //gl_FragColor.a = alpha;
-}
+}

jme3-terrain/src/main/resources/Common/MatDefs/Terrain/TerrainLighting.j3md

@@ -11,6 +11,9 @@ MaterialDef Terrain Lighting {
 
         // Are we rendering TerrainGrid
         Boolean isTerrainGrid
+        
+        // Use diffuse alpha when mixing
+        Boolean useDiffuseAlpha
 
         // Ambient color
         Color Ambient
@@ -160,6 +163,8 @@ MaterialDef Terrain Lighting {
             DIFFUSEMAP_9_SCALE : DiffuseMap_9_scale
             DIFFUSEMAP_10_SCALE : DiffuseMap_10_scale
             DIFFUSEMAP_11_SCALE : DiffuseMap_11_scale
+            
+            USE_ALPHA : useDiffuseAlpha
         }
     }
 
@@ -223,6 +228,8 @@ MaterialDef Terrain Lighting {
             DIFFUSEMAP_9_SCALE : DiffuseMap_9_scale
             DIFFUSEMAP_10_SCALE : DiffuseMap_10_scale
             DIFFUSEMAP_11_SCALE : DiffuseMap_11_scale
+            
+            USE_ALPHA : useDiffuseAlpha
         }
     }
 
@@ -289,4 +296,4 @@ MaterialDef Terrain Lighting {
         }
     }
 
-}
+}