Z.Wang@PURPLE.CS.UCL.AC.UK (Zheng Wang, Ext: 3701) (02/27/89)
Could anyone tell me whether there is an easy way in Xlib to reverse-video a window and reverse back again? What I want to do is to reverse a window representing a component when it fails and reverse it back when it comes back. Thanks in advance. Zheng
jim@EXPO.LCS.MIT.EDU (Jim Fulton) (02/28/89)
> Could anyone tell me whether there is an easy way in Xlib to > reverse-video a window and reverse back again? Depends on what you mean by "reverse". If the area in the window only has two pixel values, you can use a filled rectangle with a GC that has the following fields: function: GXxor foreground: (firstpixelvalue ^ secondpixelvalue) If you have a more complicated image on the screen, you'll have to look into allocating color planes (make sure you have a dynamic visual...) and setting up the color cells so that the arithmetic works out.