diff options
Diffstat (limited to 'src/plugins/platforms/cocoa/qcocoabackingstore.mm')
| -rw-r--r-- | src/plugins/platforms/cocoa/qcocoabackingstore.mm | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/src/plugins/platforms/cocoa/qcocoabackingstore.mm b/src/plugins/platforms/cocoa/qcocoabackingstore.mm index 8e4e928bc5..d42a723b47 100644 --- a/src/plugins/platforms/cocoa/qcocoabackingstore.mm +++ b/src/plugins/platforms/cocoa/qcocoabackingstore.mm @@ -460,12 +460,29 @@ void QCALayerBackingStore::flush(QWindow *flushedWindow, const QRegion ®ion, NSView *backingStoreView = static_cast<QCocoaWindow *>(window()->handle())->view(); NSView *flushedView = static_cast<QCocoaWindow *>(flushedWindow->handle())->view(); + // If the backingstore is just flushed, without being painted to first, then we may + // end in a situation where the backingstore is flushed to a layer with a different + // scale factor than the one it was created for in beginPaint. This is the client's + // fault in not picking up the change in scale factor of the window and re-painting + // the backingstore accordingly. To smoothing things out, we warn about this situation, + // and change the layer's contentsScale to match the scale of the back buffer, so that + // we at least cover the whole layer. This is necessary since we set the view's + // contents placement policy to NSViewLayerContentsPlacementTopLeft, which means + // AppKit will not do any scaling on our behalf. + if (m_buffers.back()->devicePixelRatio() != flushedView.layer.contentsScale) { + qCWarning(lcQpaBackingStore) << "Back buffer dpr of" << m_buffers.back()->devicePixelRatio() + << "doesn't match" << flushedView.layer << "contents scale of" << flushedView.layer.contentsScale + << "- updating layer to match."; + flushedView.layer.contentsScale = m_buffers.back()->devicePixelRatio(); + } + id backBufferSurface = (__bridge id)m_buffers.back()->surface(); if (flushedView.layer.contents == backBufferSurface) { // We've managed to paint to the back buffer again before Core Animation had time - // to flush the transaction and persist the layer changes to the window server. - // The layer already knows about the back buffer, and we don't need to re-apply - // it to pick up the surface changes, so bail out early. + // to flush the transaction and persist the layer changes to the window server, or + // we've been asked to flush without painting anything. The layer already knows about + // the back buffer, and we don't need to re-apply it to pick up any possible surface + // changes, so bail out early. qCInfo(lcQpaBackingStore).nospace() << "Skipping flush of " << flushedView << ", layer already reflects back buffer"; return; |