diff options
| author | Allan Sandfeld Jensen <allan.jensen@qt.io> | 2019-03-20 14:30:54 +0100 |
|---|---|---|
| committer | Allan Sandfeld Jensen <allan.jensen@qt.io> | 2019-03-20 14:49:58 +0000 |
| commit | 24358aaf72e94cc0c20cb6a8af8683a9c202a51a (patch) | |
| tree | 83906b8c6fdb58a5b70ccaadcb00eb356c60ec79 /src/platformsupport | |
| parent | 3ca05b2a2e80863202bdb6a225f72debbb28b8fe (diff) | |
Handle when XVisuals lose the alpha channel of the FBConfig
Sometimes the XVisual for an FBConfig have no alpha data, and thus
won't work when an alpha channel is required.
Fixes: QTBUG-74578
Change-Id: Idf05cbfcaea5edf667035939e9bc5d5df2172eec
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>
Diffstat (limited to 'src/platformsupport')
| -rw-r--r-- | src/platformsupport/glxconvenience/qglxconvenience.cpp | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/src/platformsupport/glxconvenience/qglxconvenience.cpp b/src/platformsupport/glxconvenience/qglxconvenience.cpp index 40521ef6da..6458454336 100644 --- a/src/platformsupport/glxconvenience/qglxconvenience.cpp +++ b/src/platformsupport/glxconvenience/qglxconvenience.cpp @@ -223,6 +223,7 @@ GLXFBConfig qglx_findConfig(Display *display, int screen , QSurfaceFormat format continue; } + QXlibPointer<XVisualInfo> visual(glXGetVisualFromFBConfig(display, candidate)); int actualRed; int actualGreen; int actualBlue; @@ -231,7 +232,8 @@ GLXFBConfig qglx_findConfig(Display *display, int screen , QSurfaceFormat format glXGetFBConfigAttrib(display, candidate, GLX_GREEN_SIZE, &actualGreen); glXGetFBConfigAttrib(display, candidate, GLX_BLUE_SIZE, &actualBlue); glXGetFBConfigAttrib(display, candidate, GLX_ALPHA_SIZE, &actualAlpha); - + // Sometimes the visuals don't have a depth that includes the alpha channel. + actualAlpha = qMin(actualAlpha, visual->depth - actualRed - actualGreen - actualBlue); if (requestedRed && actualRed < requestedRed) continue; |