I found a fix for my laptop at the following link. https://stackoverflow.com/questions/36672935/why-retina-screen-coordinate-value-is-twice-the-value-of-pixel-value
I have to use +:gl_qwh'', instead of the following. viewport=. 0 0,wh=. gl_qwh'' I'm looking for an openGL command to handle this situation. Stay tuned. -- (B=) ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
