Eric wing
Hi, I think I found a bug when using SDL_WINDOW_ALLOW_HIGHDPI with SDL_RenderSetLogicalSize on iOS. I use SDL_RenderSetLogicalSize for all my stuff. I just tried turning on SDL_WINDOW_ALLOW_HIGHDPI on iOS and suddenly all my touch/mouse positions are really broken/far-off-the-mark.
I actually don't have a real retina device (still) so I'm seeing this using the iOS simulator with a 6plus template.
Attached is a simple test program that can reproduce the problem. It uses RenderSetLogicalSize and draws some moving happy faces (to show the boundaries/space of the LogicalSize and that it is working correctly for that part).
When you click/touch, it will draw one more happy face where your button point is.
If you comment out SDL_WINDOW_ALLOW_HIGHDPI, everything works as expected. But if you compile with it in, the mouse coordinates seem really far off the mark. (Face appears far up and to the left.)
Alex Szpakowski on the mailing list suggests the problem is
"I believe this is a bug in SDL_Render?s platform-agnostic mouse coordinate scaling code. It assumes the units of the mouse coordinates are always in pixels, which isn?t the case where high-DPI is involved (regardless of whether iOS is used) ? they?re actually in ?DPI independent? coordinates (which matches the window size, but not the renderer output size)."
Additionally, if this is correct, the Mac under Retina is also probably affected too and "as well as any other platform SDL adds high-dpi support for in the future".
Levi Bard
In some environments, xrandr modes initialization can fail even though xrandr support is present and of a sufficient version.
(The one I encountered was an AWS instance running a virtual display)
The attached patch allows SDL to keep trying other methods if xrandr modes initialization fails (still subject to SDL_VIDEO_X11_REQUIRE_XRANDR).
Manuel
The attached patch adds support for KMS/DRM context graphics.
It builds with no problem on X86_64 GNU/Linux systems, provided the needed libraries are present, and on ARM GNU/Linux systems that have KMS/DRM support and a GLES2 implementation.
Tested on Raspberry Pi: KMS/DRM is what the Raspberry Pi will use as default in the near future, once the propietary DispmanX API by Broadcom is overtaken by open graphics stack, it's possible to boot current Raspbian system in KMS mode by adding "dtoverlay=vc4-kms-v3d" to config.txt on Raspbian's boot partition.
X86 systems use KMS right away in every current GNU/Linux system.
Simple build instructions:
$./autogen.sh
$./configure --enable-video-kmsdrm
$make
Now the clipboard isn't lost if you destroy a specific SDL_Window, as it
works on other platforms. You will still lose the clipboard data on
SDL_Quit() or process termination, but that's X11 for you; run a
Clipboard Manager daemon.
Fixes Bugzilla #3222.
Fixes Bugzilla #3718.
Eric Wasylishen
I think I found a better fix.
The problem with https://hg.libsdl.org/SDL/rev/ebdc0738b1b5 is setting the styleMask to 0 clears the NSWindowStyleMaskFullScreen bit, which then confuses Cocoa later when you try to leave fullscreen. Instead I'm just clearing the NSWindowStyleMaskResizable bit, although SetWindowStyle(window, NSWindowStyleMaskFullScreen); seems to also work.
Eric Wasylishen
Unfortunately this commit seems to have broken exiting desktop-fullscreen.
- Launch testgl2.
- Press alt+enter to go fullscreen-desktop
- Press alt+enter again. The spinning cube will freeze, and the window stays fullscreen desktop.
Simon Hug
SDL_GL_GetAttribute doesn't check if a video driver has been initialized and will access the SDL_VideoDevice pointer, which is NULL at that point.
I think all of the attributes require an initialized driver, so a simple NULL check should fix it. Patch is attached.
Jason Wyatt
After hiding the window, SDL_WINDOW_HIDDEN/SDL_WINDOW_SHOWN flags on a window are correctly updated. However on the next SDL_PumpEvents, they are set incorrectly.
This appears to be because X11_GetNetWMState does not check whether the _NET_WM_STATE property exists (it shouldn't on unmapped windows, see https://specifications.freedesktop.org/wm-spec/wm-spec-1.3.html#idm140130317598336). This results in an empty list of atoms for the state, which would imply that the window is not hidden.
(Seen on Fedora 24, Gnome)
--
Dan Ginsburg
More details on my proposed patch: I am on Kubuntu 16.04.2. I ran into this same bug, but with Jason's patch I found that actualType != None was true so the SDL_WINDOW_HIDDEN would still not be set. My fix instead is to explicitly check for whether the window is unmapped rather than relying on the returned values in XGetWindowProperty.
felix
The functions in src/render/SDL_yuv_mmx.c contain the following inline assembly snippet:
/* tap dance to workaround the inability to use %%ebx at will... */
/* move one thing to the stack... */
"pushl $0\n" /* save a slot on the stack. */
"pushl %%ebx\n" /* save %%ebx. */
"movl %0, %%ebx\n" /* put the thing in ebx. */
"movl %%ebx,4(%%esp)\n" /* put the thing in the stack slot. */
"popl %%ebx\n" /* get back %%ebx (the PIC register). */
Here's how it ended up in a binary on my old laptop:
0xb5c17dbd <ColorRGBDitherYV12MMX1X+93>: push $0x0
0xb5c17dbf <ColorRGBDitherYV12MMX1X+95>: push %ebx
0xb5c17dc0 <ColorRGBDitherYV12MMX1X+96>: mov 0xc(%esp),%ebx
0xb5c17dc4 <ColorRGBDitherYV12MMX1X+100>: mov %ebx,0x4(%esp)
0xb5c17dc8 <ColorRGBDitherYV12MMX1X+104>: pop %ebx
Apparently the compiler, oblivious to the fact that the assembly snippet manipulates the %esp register, decided to refer to the operand via that same register instead of via %ebp (I believe -fomit-frame-pointer enables this). This causes %ebx to be loaded with the wrong value, which later leads to a null pointer dereference.
Recent GCC can use the %ebx register normally: <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47602#c16>. There is even an explicit constraint "b" for allocating it.
