This bug report was migrated from our old Bugzilla tracker.

Reported in version: 2.0.3
Reported for operating system, platform: Linux, x86_64

Comments on the original bug report:

On 2014-10-29 22:19:06 +0000, Dmitry 'RCL' Rekman wrote:

If the primary X11 screen has a non-zero offset (e.g. X=2560,Y=0) as returned by SDL_GetDisplayBounds(), mouse coordinates returned by SDL_GetGlobalMouseState() will be incorrect (the said offset of the primary screen will be added to them).

The patch below (also mailed to sdl@lists.libsdl.org - http://lists.libsdl.org/pipermail/sdl-libsdl.org/2014-October/096764.html) fixes that:

diff -r bfdc18891a60 src/video/x11/SDL_x11mouse.c
--- a/src/video/x11/SDL_x11mouse.c Mon Oct 27 19:53:44 2014 -0400
+++ b/src/video/x11/SDL_x11mouse.c Wed Oct 29 16:33:25 2014 -0400
@@ -382,8 +382,14 @@
retval |= (mask & Button1Mask) ? SDL_BUTTON_LMASK : 0;
retval |= (mask & Button2Mask) ? SDL_BUTTON_MMASK : 0;
retval |= (mask & Button3Mask) ? SDL_BUTTON_RMASK : 0;

•            *x = data->x + rootx;
  

•            *y = data->y + rooty;
  

•            /* SDL_DisplayData->x,y point to screen origin, and adding them to mouse coordinates relative to root window doesn't do the right thing
  

•             * (observed on dual monitor setup with primary display being the rightmost one - mouse was offset to the right).
  

•             *
  

•             * Adding root position to root-relative coordinates seems to be a better way to get absolute position. */
  

•            XWindowAttributes root_attrs;
  

•            X11_XGetWindowAttributes(display, root, &root_attrs);
  

•            *x = root_attrs.x + rootx;
  

•            *y = root_attrs.y + rooty;
             return retval;
         }
     }
  

On 2014-10-30 17:15:08 +0000, Ryan C. Gordon wrote:

This patch is now https://hg.libsdl.org/SDL/rev/f20d288435bd, thanks!

--ryan.