commit 47789c45dfc7ba8509eedab37f1dbd70ea79da41
author Jan-Marek Glogowski <glogow@fbihome.de> Mon Oct 29 09:39:17 2018 +0100
committer Noel Grandin <noel.grandin@collabora.co.uk> Wed Oct 31 20:12:53 2018 +0100
tree 5d7bc3e58ba05e68e7742e416d9baea2d8683d9e
parent a5d990e751070eee9cab75e04f9a148443973df5

tdf#119020 always scale icons as 24bit RGB

We don't really care for the palette or even lower bitness of the
original icons, when scaling them. So just convert them to 24bit
to get the best scaling quality.

And also actually fail the OpenGL scaling for 8bit color icons,
instead of handling them as a grayscale image, which results in
"funny" luminance based color icons.

Change-Id: I62ff9e7cd45dbffba81b0db5a0252737b6189059
Reviewed-on: https://gerrit.libreoffice.org/62505
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>
(cherry picked from commit b0c475a00ced9ec1e4ef1efb9d184ee8e2a3eaab)
Reviewed-on: https://gerrit.libreoffice.org/62685
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

vcl/opengl/salbmp.cxx

diff --git a/vcl/opengl/salbmp.cxx b/vcl/opengl/salbmp.cxx
index 33fc720..6e497ff 100644
--- a/vcl/opengl/salbmp.cxx
+++ b/vcl/opengl/salbmp.cxx
@@ -582,7 +582,7 @@ bool OpenGLSalBitmap::ReadTexture()
    xContext->state().scissor().disable();
    xContext->state().stencil().disable();

    if (mnBits == 8 || mnBits == 16 || mnBits == 24 || mnBits == 32)
    if ((mnBits == 8 && maPalette.IsGreyPalette()) || mnBits == 16 || mnBits == 24 || mnBits == 32)
    {
        determineTextureFormat(mnBits, nFormat, nType);

vcl/source/image/ImplImageTree.cxx

diff --git a/vcl/source/image/ImplImageTree.cxx b/vcl/source/image/ImplImageTree.cxx
index d48cd30..039a909 100644
--- a/vcl/source/image/ImplImageTree.cxx
+++ b/vcl/source/image/ImplImageTree.cxx
@@ -181,6 +181,8 @@ void loadImageFromStream(std::shared_ptr<SvStream> const & xStream, OUString con
    {
        rParameters.mbWriteImageToCache = true; // Cache the scaled variant
        double aScaleFactor(aScalePercentage / 100.0);
        // when scaling use the full 24bit RGB values
        rParameters.mrBitmap.Convert(BmpConversion::N24Bit);
        rParameters.mrBitmap.Scale(aScaleFactor, aScaleFactor, BmpScaleFlag::Fast);
    }
}