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tdegtk/tqtcairopainter.cpp

@@ -159,6 +159,9 @@ void TQt3CairoPaintDevice::resetIntermediateSurface() {
 // Cairo however does not allow the target surface of a context to be switched, effectively preventing
 // direct drawing with dynamic switching to and from the intermediate surface on clip or ROP set/unset
 // See upstream Cairo bug report https://bugs.freedesktop.org/show_bug.cgi?id=57289
+// NOTE
+// This has been worked around by applying the same transformations, saves, and restores to both the device and intermediate surface contexts
+// If there is not much performance penalty from doing so, this method should probably be left alone
 void TQt3CairoPaintDevice::transferIntermediateSurface() {
 	bool overlayMerge = true;
 	cairo_surface_flush(m_intermediateSurface);