plotting pixels in fragment program?

From what I''ve read, being able to directly plot a pixel at an arbitrary location in a fragment program is impossible. What I''m asking though, is if there''s an alternative way to do it. Essencially I''d like to take a pixel, and calculate where offset location would be (given some stimulus) in window coords. The solution I''ve derrived so far requires a 3 step system. First step: Fragment program calculates offset locations, and stores the locations into the frame buffer Second Step: the CPU takes the frame buffer and rebuilds the texture based upon the true offset values Third Step: The created texture is placed on a screen aligned quad and sent back down the pipeline for final rendering (lighting etc is done here) The reason I have to do the reconstruction on the CPU, is because I''ve found it impossible for a fragment shader to directly handle an array of such size (Worst case, 640x480x4 array). Has anyone run into this problem? Or does anyhow have a viable solution to a work around? Thanks ~Main == Colt "MainRoach" McAnlis Programmer www.badheat.com/sinewave