Model Renderer|libgui: Don't try to bind uniforms that don't exist

The variables defined in the render block, outside any passes, apply
to all passes. However, if a pass uses a different shader, it may not
have the same variables.

doomsday/apps/client/include/render/modelrenderer.h

@@ -87,6 +87,24 @@ class ModelRenderer
      */
     void render(vispsprite_t const &pspr);
 
+    /**
+     * Looks up the name of a shader based on a GLProgram instance.
+     *
+     * @param program  Shader program. Must be a shader program
+     *                 created and owned by ModelRenderer.
+     * @return Name of the shader (in the shader bank).
+     */
+    de::String shaderName(de::GLProgram const &program) const;
+
+    /**
+     * Looks up the definition of a shader based on a GLProgram instance.
+     *
+     * @param program  Shader program. Must be a shader program
+     *                 created and owned by ModelRenderer.
+     * @return Shader definition record.
+     */
+    de::Record const &shaderDefinition(de::GLProgram const &program) const;
+
 public:
     static void initBindings(de::Binder &binder, de::Record &module);
 

doomsday/apps/client/src/render/modelrenderer.cpp

@@ -70,6 +70,7 @@ DENG2_PIMPL(ModelRenderer)
     struct Program : public GLProgram
     {
         String shaderName;
+        Record const *def = nullptr;
         int useCount = 1; ///< Number of models using the program.
     };
 
@@ -217,6 +218,7 @@ DENG2_PIMPL(ModelRenderer)
 
         std::unique_ptr<Program> prog(new Program);
         prog->shaderName = name;
+        prog->def = &ClientApp::shaders()[name].valueAsRecord(); // for lookups later
 
         LOG_RES_VERBOSE("Loading model shader \"%s\"") << name;
 
@@ -722,6 +724,16 @@ void ModelRenderer::render(vispsprite_t const &pspr)
     GLState::current().setCull(gl::Back).apply();
 }
 
+String ModelRenderer::shaderName(GLProgram const &program) const
+{
+    return static_cast<Instance::Program const &>(program).shaderName;
+}
+
+Record const &ModelRenderer::shaderDefinition(GLProgram const &program) const
+{
+    return *static_cast<Instance::Program const &>(program).def;
+}
+
 int ModelRenderer::identifierFromText(String const &text,
                                       std::function<int (String const &)> resolver) // static
 {

doomsday/apps/client/src/render/stateanimator.cpp

@@ -126,6 +126,8 @@ DENG2_PIMPL(StateAnimator)
     Record names; ///< Local context for scripts, i.e., per-object model state.
 
     ModelDrawable::Appearance appearance;
+
+    // Lookups used when drawing or updating state:
     QHash<String, int> indexForPassName;
     QHash<Variable *, int> passForMaterialVariable;
 
@@ -221,7 +223,7 @@ DENG2_PIMPL(StateAnimator)
 
         initVariables();
 
-        // Set up the appearance.
+        // Set up the model drawing parameters.
         if(!self.model().passes.isEmpty())
         {
             appearance.drawPasses = &self.model().passes;
@@ -258,7 +260,10 @@ DENG2_PIMPL(StateAnimator)
         }
         else
         {
-            for(int i = 0; i < passCount; ++i) appearance.passMaterial << 0;
+            for(int i = 0; i < passCount; ++i)
+            {
+                appearance.passMaterial << 0;
+            }
         }
         appearance.passMask.resize(passCount);
 
@@ -499,6 +504,18 @@ DENG2_PIMPL(StateAnimator)
         }
     }
 
+    /**
+     * Checks if a shader definition has a declaration for a variable.
+     *
+     * @param program  Shader definition.
+     * @param uniform  Uniform.
+     * @return @c true, if a variable exists matching @a uniform.
+     */
+    static bool hasDeclaredVariable(Record const &shaderDef, GLUniform const &uniform)
+    {
+        return shaderDef.hasMember(String::fromUtf8(uniform.name()));
+    }
+
     /**
      * Binds or unbinds uniforms that apply to all rendering passes.
      *
@@ -522,11 +539,17 @@ DENG2_PIMPL(StateAnimator)
                           de::String const &passName,
                           BindOperation operation) const
     {
+        auto const &modelRenderer = ClientApp::renderSystem().modelRenderer();
+
         auto const vars = passVars.constFind(passName);
         if(vars != passVars.constEnd())
         {
             for(auto i : vars.value())
             {
+                if(!hasDeclaredVariable(modelRenderer.shaderDefinition(program),
+                                        *i->uniform))
+                    continue;
+
                 if(operation == Bind)
                 {
                     i->updateUniform();

doomsday/sdk/libgui/include/de/graphics/glprogram.h

@@ -13,7 +13,7 @@
  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
  * General Public License for more details. You should have received a copy of
  * the GNU Lesser General Public License along with this program; if not, see:
- * http://www.gnu.org/licenses</small> 
+ * http://www.gnu.org/licenses</small>
  */
 
 #ifndef LIBGUI_GLPROGRAM_H
@@ -106,6 +106,8 @@ class LIBGUI_PUBLIC GLProgram : public Asset
 
     int glUniformLocation(char const *uniformName) const;
 
+    bool glHasUniform(char const *uniformName) const;
+
     /**
      * Determines which attribute location is used for a particular attribute semantic.
      * These locations are available after the program has been successfully built

doomsday/sdk/libgui/src/graphics/glprogram.cpp

@@ -494,13 +494,12 @@ GLuint GLProgram::glName() const
 
 int GLProgram::glUniformLocation(char const *uniformName) const
 {
-    GLint loc = glGetUniformLocation(d->name, uniformName);
-    if(loc < 0)
-    {
-        LOG_AS("GLProgram");
-        LOGDEV_GL_WARNING("Could not find uniform '%s'") << uniformName;
-    }
-    return loc;
+    return glGetUniformLocation(d->name, uniformName);
+}
+
+bool GLProgram::glHasUniform(char const *uniformName) const
+{
+    return glUniformLocation(uniformName) >= 0;
 }
 
 int GLProgram::attributeLocation(AttribSpec::Semantic semantic) const