hi (chris), I know that I am bothering you, but I think you (chris) are the only one who can help with the MultiTexture stuff and therefore I send another mail. I don't know how to get gl_MultiTexCoord1 and higher working. I cannot reference glsl to read from any other than gl_MultiTexCoord0. I looked into gem code for glsl_vertex and glsl_program, and did not find something which looks releated to multitextures. then I looked into GemShape.cpp and rectangle.cpp and found a variable curCoord. and a section in rectangle that is related to that and commented out. I am (still) no C programmer and don't know the history of gem (why parts are commented out...?), but it seems that these two things, in connection with SetVertex(GemState* state,float x, float y, float z, float tx, float ty,int curCoord) could be part of the problem. thanks, marius.