X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Ffrontends%2Fqt4%2FGuiWorkArea.cpp;h=95cff6d5ec30f8c7d8de4903e3750115022cff16;hb=b7f6b979d0f889f08e735f35378bb20ba3788b4b;hp=5ef177dc37fb12bb8f5685f1459d015d90a3ebc1;hpb=7c35081d0c4e48b2ff73c5a11c5446f5288802af;p=lyx.git

diff --git a/src/frontends/qt4/GuiWorkArea.cpp b/src/frontends/qt4/GuiWorkArea.cpp
index 5ef177dc37..95cff6d5ec 100644
--- a/src/frontends/qt4/GuiWorkArea.cpp
+++ b/src/frontends/qt4/GuiWorkArea.cpp
@@ -239,13 +239,27 @@ SyntheticMouseEvent::SyntheticMouseEvent()
 
 
 GuiWorkArea::Private::Private(GuiWorkArea * parent)
-: p(parent), buffer_view_(0), lyx_view_(0),
-  caret_(0), caret_visible_(false),
-  need_resize_(false), preedit_lines_(1),
-  last_pixel_ratio_(1.0),
-  completer_(new GuiCompleter(p, p)), dialog_mode_(false), shell_escape_(false),
-  read_only_(false), clean_(true), externally_modified_(false)
-{
+: p(parent), buffer_view_(0), lyx_view_(0), caret_(0),
+  caret_visible_(false), need_resize_(false), preedit_lines_(1),
+  last_pixel_ratio_(1.0), completer_(new GuiCompleter(p, p)),
+  dialog_mode_(false), shell_escape_(false), read_only_(false),
+  clean_(true), externally_modified_(false)
+{
+/* Qt on macOS and Wayland does not respect the
+ * Qt::WA_OpaquePaintEvent attribute and resets the widget backing
+ * store at each update. Therefore, we use our own backing store in
+ * these two cases. */
+#if QT_VERSION >= 0x050000
+	use_backingstore_ = guiApp->platformName() == "cocoa"
+		|| guiApp->platformName().contains("wayland");
+#else
+#  ifdef Q_OS_MAC
+	use_backingstore_ = true;
+#  else
+	use_backingstore_ = false;
+#  endif
+#endif
+
 	int const time = QApplication::cursorFlashTime() / 2;
 	if (time > 0) {
 		caret_timeout_.setInterval(time);
@@ -429,12 +443,16 @@ void GuiWorkArea::startBlinkingCaret()
 	if (view().busy())
 		return;
 
-	Point p;
-	int h = 0;
-	d->buffer_view_->caretPosAndHeight(p, h);
-	// Don't start blinking if the cursor isn't on screen.
-	if (!d->buffer_view_->cursorInView(p, h))
-		return;
+	// we cannot update geometry if not ready and we do not need to if
+	// caret is not in view.
+	if (!d->buffer_view_->buffer().undo().activeUndoGroup()) {
+		Point p;
+		int h = 0;
+		d->buffer_view_->caretPosAndHeight(p, h);
+		// Don't start blinking if the cursor isn't on screen.
+		if (!d->buffer_view_->cursorInView(p, h))
+			return;
+	}
 
 	d->showCaret();
 
@@ -597,6 +615,11 @@ void GuiWorkArea::Private::resizeBufferView()
 
 void GuiWorkArea::Private::updateCaretGeometry()
 {
+	// we cannot update geometry if not ready and we do not need to if
+	// caret is not in view.
+	if (buffer_view_->buffer().undo().activeUndoGroup())
+		return;
+
 	Point point;
 	int h = 0;
 	buffer_view_->caretPosAndHeight(point, h);
@@ -1257,6 +1280,41 @@ void GuiWorkArea::Private::paintPreeditText(GuiPainter & pain)
 }
 
 
+void GuiWorkArea::Private::resetScreen()
+{
+	if (use_backingstore_) {
+		int const pr = p->pixelRatio();
+		screen_ = QImage(static_cast<int>(pr * p->viewport()->width()),
+		                 static_cast<int>(pr * p->viewport()->height()),
+		                 QImage::Format_ARGB32_Premultiplied);
+#  if QT_VERSION >= 0x050000
+		screen_.setDevicePixelRatio(pr);
+#  endif
+	}
+}
+
+
+QPaintDevice * GuiWorkArea::Private::screenDevice()
+{
+	if (use_backingstore_)
+		return &screen_;
+	else
+		return p->viewport();
+}
+
+
+void GuiWorkArea::Private::updateScreen(QRectF const & rc)
+{
+	if (use_backingstore_) {
+		QPainter qpain(p->viewport());
+		double const pr = p->pixelRatio();
+		QRectF const rcs = QRectF(rc.x() * pr, rc.y() * pr,
+		                          rc.width() * pr, rc.height() * pr);
+		qpain.drawImage(rc, screen_, rcs);
+	}
+}
+
+
 void GuiWorkArea::paintEvent(QPaintEvent * ev)
 {
 	// Do not trigger the painting machinery if we are not ready (see