i have a little problem with planar shadow when i use blending. when i use blendig some spots shown in the shadow, how can i remove this spots?! problem shown at this shot: http://psware.persiangig.com/e/KGE_test/shadow.PNG and this is my code for blending: glEnable(GL_EXT_blend_color); glBlendColor(0.5,0.5,0.5,0.5); glBlendFunc(GL_CONSTANT_ALPHA,GL_ONE_MINUS_CONSTANT_COLOR ); ( i must use blend-color)

I couldn't see any spots :O, but you want
GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA respectively as your two parameters.