openkylin
/
kwin
mirror of https://gitee.com/openkylin/kwin.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

plugins/qpa: initialize buffer in backingstore

This commit is contained in:
hxf 2023-05-23 17:09:00 +08:00 committed by MouseZhang
parent ee34562420
commit 8f2e59a943
2 changed files with 14 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
src/plugins/qpa/backingstore.cpp
View File

@ -49,6 +49,18 @@ void BackingStore::resize(const QSize &size, const QRegion &staticContents)
m_frontBuffer.setDevicePixelRatio(devicePixelRatio);
}
void BackingStore::beginPaint(const QRegion &region)
{
if (m_backBuffer.hasAlphaChannel()) {
QPainter p(paintDevice());
p.setCompositionMode(QPainter::CompositionMode_Source);
const QColor blank = Qt::transparent;
for (const QRect &rect : region) {
p.fillRect(rect, blank);
}
}
}
static QRect scaledRect(const QRect &rect, qreal devicePixelRatio)
{
return QRect(rect.topLeft() * devicePixelRatio, rect.size() * devicePixelRatio);
@ -57,6 +69,7 @@ static QRect scaledRect(const QRect &rect, qreal devicePixelRatio)
static void blitImage(const QImage &source, QImage &target, const QRegion &region)
{
QPainter painter(&target);
painter.setCompositionMode(QPainter::CompositionMode_Source);
for (const QRect &rect : region) {
painter.drawImage(rect, source, scaledRect(rect, source.devicePixelRatio()));
}

1
src/plugins/qpa/backingstore.h
View File

@ -28,6 +28,7 @@ public:
QPaintDevice *paintDevice() override;
void flush(QWindow *window, const QRegion &region, const QPoint &offset) override;
void resize(const QSize &size, const QRegion &staticContents) override;
void beginPaint(const QRegion &region) override;
private:
QImage m_backBuffer;