# How to interactively modify shadow mapping in RenderMonkey?

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kovacsp    306
Hi, I'm trying to make a simple prototype shadow mapping in RenderMonkey, that is simple enough for me to understand (all samples I have found on the net make blurred, tricky shadow maps, and for the first step, I wanted one that is the simplest possible variant). - I can post the shaders if someone is interested. Now here is my problem: I have two passes. The first one renders the shadow map using the World-View-Projection matrix of the light being the camera. I can fill in this matrix by hand, or I can use a camera, and using a predefined matrix, I can get the values automatically. Then, in the second pass, I need two WVP matrices: one for my real camera, and one for the "light-camera". If I use a predefined WVP matrix, then it will give the values of my real camera, so I don't have the light WVP. If I reference the light-camera, then my predefined matrix will have the light WVP, but then, I don;t have the camera WVP. I cannot reference a matrix in another pass, and I cannot even copy the values of a predefined matrix into a non-oredefined one, just by hand, one by one. This is what I am forced to do now, but I'm wondrring if there is an easier solution. Thanks for your help, Peter