Hi guys, I have a couple of questions, the answer to which is probably very straightforward. Whenever I want to render a model with a shader, do I need to set the parameters each time or are they stored? Obviously if they've changed then I'd set them, but would it be worth caching the values on the CPU side and only setting the differing ones? Secondly, if most of my shaders need a viewProjection matrix, what is the best way to implement this? Do I need to know the parameter name for each shader (or use a standard name), store a handle to that parameter, and each time I want to render using the shader set the matrix via the handle? Repeat for all the effects and surfaces I'm rendering? Do you have a set of standard parameters which are always set on an effect?