yukijoou/kwin
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

backends/drm: fix flicker with rotation on mobile

Browse source 
When we use a shadow buffer, we always render to the whole surface - setting
the damage region is incorrect and invokes undefined behavior. On the Lima
driver this caused flickering on screen rotation.
To fix this, don't set a damage region when we use a shadow buffer, which is
effectively setting the damage region to the full surface
This commit is contained in:
Xaver Hugl 2022-06-27 18:55:09 +02:00 committed by Vlad Zahorodnii
parent 3d3fcd7ab4
commit 29625218d3
1 changed files with 4 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
src/backends/drm/egl_gbm_layer_surface.cpp
View file

@ -105,6 +105,10 @@ OutputLayerBeginFrameInfo EglGbmLayerSurface::startRendering(const QSize &buffer
void EglGbmLayerSurface::aboutToStartPainting(DrmOutput *output, const QRegion &damagedRegion)
{
if (m_shadowBuffer) {
// with a shadow buffer, we always fully damage the surface
return;
}
if (m_gbmSurface && m_gbmSurface->bufferAge() > 0 && !damagedRegion.isEmpty() && m_eglBackend->supportsPartialUpdate()) {
QVector<EGLint> rects = output->regionToRects(damagedRegion);
const bool correct = eglSetDamageRegionKHR(m_eglBackend->eglDisplay(), m_gbmSurface->eglSurface(), rects.data(), rects.count() / 4);