Hi guys : I''m triying to compile a piece of code from Open GL Super Bible.The code complete is : tess = gluNewTess(); gluTessCallback(tess, GLU_BEGIN, glBegin); gluTessCallback(tess, GLU_VERTEX, glVertex3dv); gluTessCallback(tess, GLU_END, glEnd); gluBeginPolygon(tess); gluTessVertex(tess, outside[0], outside[0]); gluTessVertex(tess, outside[1], outside[1]); gluTessVertex(tess, outside[2], outside[2]); gluTessVertex(tess, outside[3], outside[3]); gluTessVertex(tess, outside[4], outside[4]); gluTessVertex(tess, outside[5], outside[5]); gluTessVertex(tess, outside[6], outside[6]); gluNextContour(tess, GLU_INTERIOR); gluTessVertex(tess, inside[0], inside[0]); gluTessVertex(tess, inside[1], inside[1]); gluTessVertex(tess, inside[2], inside[2]); gluEndPolygon(tess); gluDeleteTess(tess); But I have got the errors : error C2664: ''gluTessCallback'' : cannot convert parameter 3 from ''void (unsigned int)'' to ''void (__stdcall *)(void)'' error C2664: ''gluTessCallback'' : cannot convert parameter 3 from ''void (unsigned int)'' to ''void (__stdcall *)(void)'' at the two first lines with gluTessCallback(GLU_BEGIN and GLU_VERTEX).I thought it was a problem with the cast of the funtions,but i haven''t been able to do. Any idea?? Thanks