Sdl.Blendval mode_none : modeval mode_blend : modeval mode_add : modeval mode_mod : modeval add : operationval subtract : operationval rev_subtract : operationval minimum : operationval maximum : operationval zero : factorval one : factorval src_color : factorval one_minus_src_color : factorval src_alpha : factorval one_minus_src_alpha : factorval dst_color : factorval one_minus_dst_color : factorval dst_alpha : factorval one_minus_dst_alpha : factor