4 Replies Latest reply on Jun 3, 2010 8:29 AM by nou

    Driver optimizations of uniform variables inside the vertex shader? (OpenGL)

    godlike

      Now that the gl_*Matrix is deprecated we need to supply the shaders with our own matrices via uniforms. So far so good.

      Imagine I have the following part of a vertex shader:

      ...
      uniform mat4 my_projection_mat;
      uniform mat4 my_modelview_mat;
      attribute vec3
      my_vertex_pos;
      ...
      gl_Position = (my_projection_mat * my_modelview_mat) * vec4(my_vertex_pos, 1.0);
      ...

      My question is: Will the AMD driver perform the "my_projection_mat * my_modelview_mat" multiplication for every vertex? Or it will understand that this calculation needs to be done only once?