   opgl 2d just draw in a windows size nXm pixel 0,0 and 0,1 and so on?
  Hi,I just want to find a way to draw directly in a window pixel by pixel.thanks in advance,Alex   
  Use glOrtho(0, width, 0, height) to setup a coordinate system matching the pixel size of the viewport. From that, you need to be aware of the rasterization rules for points, lines and filled primitives to ensure proper and portable rendering. Pixel perfect rendering is not entirely trivial to get correct.   