1. A method for controlling image resolution in graphics systems at runtime comprising: Intercepting and analyzing the stream of commands and Shaders of the running application at run time; (i) in the event that an on-the-fly change of resolution is required; the said change is made by modification of the: a. Shader assembly code, or b. graphics library commands, or c. Shader assembly code and graphics library commands (ii) in the event that no change of resolution is required; no change is made.