Volker Sauer wrote:
It's been exacerbated by the fact that there is no official means for accessing the 2nd screen VideoLUTs when Xinerama is running, even though it is possible in some cases.In which cases is it possible? With which card/driver combinations?
If it's real Xinerama, rather than a faked up Xinerama, it tends to work. Xinerama makes multiple X11 screens look like one large screen by intercepting some of the X11 protocol to the multiple screens, but it doesn't intercept the XF86VidMode extension calls, so they are able to talk to the different underlying screens VideoLUTs. If the Xinerama extension is faked by the driver, it usually doesn't fake the multiple underlying screens, XF86VidMode can't access them. Graeme Gill.