interesting info thanks. Could nvidia users who have this issue check their driver options: Option "SWCursor" "boolean" Enable or disable software rendering of the X cursor. Default: off. Option "HWCursor" "boolean" Enable or disable hardware rendering of the X cursor. Default: on. Nvidia drivers have a couple of options todo with the cursor, It might be worth setting SWcursor on and HWcursor off to test
I've created a minimal sample using opengl and xcursor; and have managed to reproduce the bug. XDefineCursor with >64x64 cursor image specified will cause this issue on NVidia hardware. I will have to wait until I get home to to verify this on my AMD chipset. Since all your cursors are 100x100, this issue will occur every time you call setCursor Also, thanks, Uber, for not stripping debug symbols; XCursor has practically NO tutorials... tiny code update: replace "ReplaceCursor" with this, it's just a minor change Code: void ReplaceCursor() { XcursorImage* image = XcursorImageCreate(64, 64); for (int i = 0; i < image->width * image->height; i++) image->pixels[i] = i % 8 == 0 ? 0xffffffff : 0; image->xhot = image->width / 2; image->yhot = image->height / 2; cursor = XcursorImageLoadCursor(display, image); XcursorImageDestroy(image); XDefineCursor(display, window, cursor); XFlush(display); }
I also want to notice to build this text on deb-based you probably need to use add "-lX11" to LDLIBSOPTIONS. Also you choose very strange example which have shader broken for FOSS drivers...
I just used this: http://ogldev.atspace.co.uk/www/tutorial07/tutorial07.html tutorial. It's a standard netbeans c++ project so you can open and debug it in there, build on ubuntu (deb-based)
I managed to compile it without -lX11 as well on Kubuntu 12.04. Also, I can confirm that with a 64x64 cursor everything is fine, but with a 65x65 cursor, the cursor behaves as in PA. That is, flickering when moving and invisible when stationary. This is on Nvidia with 304.88 drivers by the way.
I've just confirmed the behavior for my AMD chipset: a 64x64 cursor operates without error on NVidia and AMD a 65x65 (or greator) cursor causes a backbuffer redraw issue in the rectangle covered by the mouse cursor on NVidia a 65x65 (or greator) cursor causes a total backbuffer redraw issue over the entire window on AMD. I can only hypothesize; but I believe eeyrjmr's cursor rendering options may be the culprit. On up to a 64x64 cursor, it appears the Compositor is able to compose the mouse in hardware, leaving no rendering issues. Any larger, and a software fallback mode in X11 seems to keep one of the backbuffers permanently locked, which means the compositor cannot draw to it correctly, and thus the cursor error occurs. The free drivers are probably able to reduce this error by accepting larger hardware-accellerated image buffers, it would be interesting to see at what point free drivers start having the issue. They may be stable all the way up to the GPU's maximum texture size, or they may just bump the maximum to 128x128. As for PA, I can see 2 solutions for Uber: reduce all cursor sizes to maximum 64x64, OR somehow enable full-screen rendering without output redirection (compositors work by redirecting window output to a gl texture) The former is far easier, and could be accomplished by resizing cursors for everyone or just scaling the images in linux before replacing them. The latter is much more difficult, is distro, compositor, and gpu specific, and requires far too much linux-specific work for me to recommend it.
Free drivers have no back buffering issues, but flickering happend in some cases. It's can work fine without flickering, but after some action clickeing starting. I enable FPS counter (which actually have 60fps) and flickering stopped, but it's not seems to be related on FPS/VSync because moment ago cursor working normal without FPS counter on same point of view. It's really weird.
not my options, just Nvidia's 64x64 is prob the limit then of binary drivers - they prob didn't think anyone would want any bigger or was some arbitrary limit set since a limit was needed. maybe the binary drv could up this, but for now it seems all Uber need todo is create a 64x64 cursor
I added code to clamp the cursor size to 64x64 on Linux. Turns out our cursors had a lot of blank padding around them so the cursors should still look fine even when clamped. Alas, I can't promise when the next build is going out, what with PAX going on right now. But it should be soon. -William
Hey guys, nice to hear that u put efford into the Linux version! I've the exact same problem. With xcompmgr (don't need the -c for the shadows) it get's better. Anyway, I had to make a new user and use another WM to get it working. I'm kinda new to this kinda stuff, so if I can help u by providing data, I would need some help and explanation what u need and how.
I can confirm, build 52973, has fixed the cursor bug for me too. System specs: i7 980X Extreme cpu Geforce GTX 580 gpu (1.5 GiB) 24 GiB ram SSD (6 Gbps) Kubuntu Linux 12.04 LTS 64-bit Linux kernel 3.5.0-18-generic Xorg 11, version 1.11.3 Nvidia driver version 325.15 OpenGL version 4.3.0
