opengl's drawBitmap() should also scale properly if needed (tdf#123372)

If the bitmap to be drawn will need to be scale for drawing, OpenGL
handles this by scaling, but the scaling is of poor quality. Other
backends scale in such a case with a good quality, and e.g. opengl's
drawAlphaBitmap() also does the same check, so copy that check
to drawBitmap() as well.

Change-Id: If6a457c69c6676d03fa4046b9910683f51479d21
Reviewed-on: https://gerrit.libreoffice.org/69556
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/vcl/opengl/gdiimpl.cxx b/vcl/opengl/gdiimpl.cxx
index 90922d737eb3..3a15755eb7a9 100644
--- a/vcl/opengl/gdiimpl.cxx
+++ b/vcl/opengl/gdiimpl.cxx
@@ -1743,7 +1743,19 @@ void OpenGLSalGraphicsImpl::drawBitmap( const SalTwoRect& rPosAry, const SalBitm
 
     VCL_GL_INFO( "::drawBitmap" );
     PreDraw();
-    DrawTexture( rTexture, rPosAry );
+    if (rPosAry.mnSrcWidth  != rPosAry.mnDestWidth ||
+        rPosAry.mnSrcHeight != rPosAry.mnDestHeight)
+    {
+        basegfx::B2DPoint aNull(rPosAry.mnDestX,rPosAry.mnDestY);
+        basegfx::B2DPoint aX(rPosAry.mnDestX + rPosAry.mnDestWidth, rPosAry.mnDestY);
+        basegfx::B2DPoint aY(rPosAry.mnDestX, rPosAry.mnDestY + rPosAry.mnDestHeight);
+        OpenGLTexture mask; // no mask set
+        DrawTransformedTexture(rTexture, mask, aNull, aX, aY);
+    }
+    else
+    {
+        DrawTexture( rTexture, rPosAry );
+    }
     PostDraw();
 }