Qt5 implement 4bit => 32bit bitmap conversion

Some of the PNG icons are 4bit palette based PNG images.
This implements the conversation function for the most
common 4bit case, so we don't rely on some generic handling.

All other non-4bit conversions can be handled by Qt.

Change-Id: I4ddd744fb7166fc3a6992b6be6c250c2adb99ca5

1 files changed, 18 insertions, 4 deletions

diff --git a/vcl/qt5/Qt5Graphics_GDI.cxx b/vcl/qt5/Qt5Graphics_GDI.cxx
index b58f18e4b59b..971b85f705fe 100644
--- a/vcl/qt5/Qt5Graphics_GDI.cxx
+++ b/vcl/qt5/Qt5Graphics_GDI.cxx
@@ -403,8 +403,12 @@ void Qt5Graphics::drawBitmap(const SalTwoRect& rPosAry, const SalBitmap& rSalBit
     assert(rPosAry.mnSrcHeight == rPosAry.mnDestHeight);
 
     Qt5Painter aPainter(*this);
-
-    const QImage* pImage = static_cast<const Qt5Bitmap*>(&rSalBitmap)->GetQImage();
+    Qt5Bitmap aRGBABitmap;
+    if (rSalBitmap.GetBitCount() == 4)
+        aRGBABitmap.Create(rSalBitmap, 32);
+    const QImage* pImage = (rSalBitmap.GetBitCount() != 4)
+                               ? static_cast<const Qt5Bitmap*>(&rSalBitmap)->GetQImage()
+                               : aRGBABitmap.GetQImage();
     assert(pImage);
 
     aPainter.drawImage(
@@ -475,7 +479,12 @@ static bool getAlphaImage(const SalBitmap& rSourceBitmap, const SalBitmap& rAlph
         return false;
     }
 
-    const QImage* pBitmap = static_cast<const Qt5Bitmap*>(&rSourceBitmap)->GetQImage();
+    Qt5Bitmap aRGBABitmap;
+    if (rSourceBitmap.GetBitCount() == 4)
+        aRGBABitmap.Create(rSourceBitmap, 32);
+    const QImage* pBitmap = (rSourceBitmap.GetBitCount() != 4)
+                                ? static_cast<const Qt5Bitmap*>(&rSourceBitmap)->GetQImage()
+                                : aRGBABitmap.GetQImage();
     const QImage* pAlpha = static_cast<const Qt5Bitmap*>(&rAlphaBitmap)->GetQImage();
     rAlphaImage = pBitmap->convertToFormat(Qt5_DefaultFormat32);
 
@@ -532,7 +541,12 @@ bool Qt5Graphics::drawTransformedBitmap(const basegfx::B2DPoint& rNull, const ba
         return false;
     else
     {
-        const QImage* pBitmap = static_cast<const Qt5Bitmap*>(&rSourceBitmap)->GetQImage();
+        Qt5Bitmap aRGBABitmap;
+        if (rSourceBitmap.GetBitCount() == 4)
+            aRGBABitmap.Create(rSourceBitmap, 32);
+        const QImage* pBitmap = (rSourceBitmap.GetBitCount() != 4)
+                                    ? static_cast<const Qt5Bitmap*>(&rSourceBitmap)->GetQImage()
+                                    : aRGBABitmap.GetQImage();
         aImage = pBitmap->convertToFormat(Qt5_DefaultFormat32);
     }