diff options
| author | Morten Sørvig <morten.sorvig@qt.io> | 2022-04-12 12:43:07 +0200 |
|---|---|---|
| committer | Morten Sørvig <morten.sorvig@qt.io> | 2022-04-19 14:46:18 +0200 |
| commit | c78925f487c82f6ffbf9a8bceda8bef4b214bc3b (patch) | |
| tree | 9123652d2cc44dd6b9a6fb144b1436d73988aeea /src/plugins/platforms/wasm/qwasmbackingstore.cpp | |
| parent | e629efc82c2e26559159abfe44d8414997bc3d68 (diff) | |
wasm: propagate QWindow format to backing store
Qt backing store images should have alpha iff that was
requested by the QWindow's surface format. This changes
wasm to be in line with the other platforms, and enables
use of transparency for Qt windows.
Change beginPaint() to clear the backing store only
if the format/image has alpha. This is also established
behavior Qt's backing stores.
Change-Id: Idafe658e24d864f7c4f9e68ee39cb409982b5852
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>
Reviewed-by: David Skoland <david.skoland@qt.io>
Diffstat (limited to 'src/plugins/platforms/wasm/qwasmbackingstore.cpp')
| -rw-r--r-- | src/plugins/platforms/wasm/qwasmbackingstore.cpp | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/src/plugins/platforms/wasm/qwasmbackingstore.cpp b/src/plugins/platforms/wasm/qwasmbackingstore.cpp index 90fb168288d..83afa568fb6 100644 --- a/src/plugins/platforms/wasm/qwasmbackingstore.cpp +++ b/src/plugins/platforms/wasm/qwasmbackingstore.cpp @@ -156,17 +156,22 @@ void QWasmBackingStore::beginPaint(const QRegion ®ion) resize(backingStore()->size(), backingStore()->staticContents()); QPainter painter(&m_image); - painter.setCompositionMode(QPainter::CompositionMode_Source); - const QColor blank = Qt::transparent; - for (const QRect &rect : region) - painter.fillRect(rect, blank); + + if (m_image.hasAlphaChannel()) { + painter.setCompositionMode(QPainter::CompositionMode_Source); + const QColor blank = Qt::transparent; + for (const QRect &rect : region) + painter.fillRect(rect, blank); + } } void QWasmBackingStore::resize(const QSize &size, const QRegion &staticContents) { Q_UNUSED(staticContents); - m_image = QImage(size * window()->devicePixelRatio(), QImage::Format_RGB32); + QImage::Format format = window()->format().hasAlpha() ? + QImage::Format_ARGB32_Premultiplied : QImage::Format_RGB32; + m_image = QImage(size * window()->devicePixelRatio(), format); m_image.setDevicePixelRatio(window()->devicePixelRatio()); m_recreateTexture = true; } |