Model Renderer|GL: Shader defines texture mapping for itself

The shader definition can specify which texture map is to be bound
to which position in the vertex attributes. The model renderer checks
this information when a model is being prepared for drawing.

doomsday/client/net.dengine.client.pack/renderer.pack/shaders/model.dei

@@ -2,6 +2,8 @@ group model {
     # Shader for skeletal animation and generic per-pixel lighting:
     # diffuse color, normal map, emission map, specular intensity.
     shader skeletal.normal_specular_emission {
+        # Mapping when used with ModelDrawable.
+        textureMapping <diffuse, normals, specular, emission>
         vertex = "
             uniform highp mat4 uMvpMatrix;
             uniform highp mat4 uBoneMatrices[64];

doomsday/client/src/render/modelrenderer.cpp

@@ -37,6 +37,7 @@ static String const DEF_FRONT_VECTOR("front");
 DENG2_PIMPL(ModelRenderer)
 , DENG2_OBSERVES(filesys::AssetObserver, Availability)
 , DENG2_OBSERVES(Bank, Load)
+, DENG2_OBSERVES(ModelDrawable, AboutToGLInit)
 {
 #define MAX_LIGHTS  4
 
@@ -59,7 +60,7 @@ DENG2_PIMPL(ModelRenderer)
     Instance(Public *i) : Base(i)
     {
         observer.audienceForAvailability() += this;
-        bank.audienceForLoad() += this;
+        bank.audienceForLoad() += this;        
     }
 
     void init()
@@ -93,14 +94,15 @@ DENG2_PIMPL(ModelRenderer)
 
         uTex = *atlas;
 
+        /*
         // All loaded items should use this atlas.
         bank.iterate([this] (DotPath const &path)
         {
             if(bank.isLoaded(path))
             {
-                setupModel(bank.model(path), path);
+                setupModel(bank.model(path));
             }
-        });
+        });*/
     }
 
     void deinit()
@@ -134,15 +136,29 @@ DENG2_PIMPL(ModelRenderer)
      *
      * @param model  Model to configure.
      */
-    void setupModel(ModelDrawable &model, String const &path)
+    void setupModel(ModelDrawable &model)
     {
         if(atlas)
         {
             model.setAtlas(*atlas);
-            model.setTextureMapping(ModelDrawable::diffuseNormalsSpecularEmission());
+
             model.setDefaultTexture(ModelDrawable::Normals,  defaultNormals);
             model.setDefaultTexture(ModelDrawable::Emission, defaultEmission);
             model.setDefaultTexture(ModelDrawable::Specular, defaultSpecular);
+
+            // Use the texture mapping specified in the shader. This has to be done
+            // only now because earlier we may not have the shader available yet.
+            Record const &def = ClientApp::shaders().names().subrecord("model.skeletal.normal_specular_emission");
+            if(def.has("textureMapping"))
+            {
+                ModelDrawable::Mapping mapping;
+                for(Value const *value : def.geta("textureMapping").elements())
+                {
+                    mapping << ModelDrawable::textToTextureMap(value->asText());
+                }
+                //qDebug() << "using mapping" << mapping;
+                model.setTextureMapping(mapping);
+            }
         }
         else
         {
@@ -151,6 +167,11 @@ DENG2_PIMPL(ModelRenderer)
         model.setProgram(program);
     }
 
+    void modelAboutToGLInit(ModelDrawable &model)
+    {
+        setupModel(model);
+    }
+
     /**
      * When model assets have been loaded, we can parse their metadata to see if there
      * are any animation sequences defined. If so, we'll set up a shared lookup table
@@ -162,7 +183,7 @@ DENG2_PIMPL(ModelRenderer)
     {
         // Models use the shared atlas.
         ModelDrawable &model = bank.model(path);
-        setupModel(model, path);
+        model.audienceForAboutToGLInit() += this;
 
         auto const asset = App::asset(path);