Uniform buffers in OpenGL

In OpenGL, the uniform buffer "Binding Index" is the equivalent of DX11's buffer slots. However, GL has many, many more indices available for than DX - about 35000.

You should therefore NEVER use the same index to bind two different blocks in the same frame - there's simply no need.

e.g

 static int lastBindingIndex=21;
 if(lastBindingIndex>=GL_MAX_UNIFORM_BUFFER_BINDINGS)
  lastBindingIndex=1;
 bindingIndex=lastBindingIndex;
 lastBindingIndex++;
 
 glUniformBlockBinding(program,indexInShader,bindingIndex);