hello,

the aim of my program is to move a 50x50 pixel (pic_a) immage over a 500x500 pixel (pic_b) image by moving the mouse over the big image.
also, i have to copy a part of pic_b to produce pic_a and change to rgb color into a grayscale for pic_a. In the end the grayscaled pic_a
has to move over pic_b while exactly matching in content. i know it is hard to explain but i just hope that anybody can give me an idea how to
make a copy, save this and put it into the front. i am using c++ and opengl and think i need several buffers and switch them while moving???

thanks in advance,
patrick