Ok, so this proves my point. The unwanted "change" somewhere in the X/GL stack is that the visual with the composite alpha channels is now "accidentally" chosen by default whereas the applications expect the alpha channel to be ignored.
I just decompiled Minecraft and hacked the calls to glClearColor to set the alpha value to "1.0" and this "corrects" the output (at least for Minecraft...). gcc -o test test.c -lX11 -lXrender -lGL && ./test Prints: visual 0: alphaMask = 255 visual 1: alphaMask = 0 visual 2: alphaMask = 0 visual 3: alphaMask = 0 visual 4: alphaMask = 0 visual 5: alphaMask = 0 visual 6: alphaMask = 0 visual 7: alphaMask = 0 Which means that the first visual proposed contains the alpha mask causing unwanted alpha compositing. ** Attachment added: "GLXFBconfig alphaMask dump: gcc -o test test.c -lX11 -lXrender -lGL && ./test" https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1277905/+attachment/4015392/+files/test.c -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1277905 Title: Game windows (minecraft, titan attacks, maybe others) on Intel are transparent and no longer playable To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1277905/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
