include/vcl/skia/SkiaHelper.hxx | 1 +
vcl/skia/SkiaHelper.cxx | 3 +++
vcl/skia/gdiimpl.cxx | 10 ++++++++++
vcl/source/outdev/bitmap.cxx | 2 +-
4 files changed, 15 insertions(+), 1 deletion(-)
New commits:
commit cde3a60e99ea52fb5d5e27963c74f1526a0560c7
Author: Patrick Luby <plub...@neooffice.org>
AuthorDate: Thu Jul 20 09:22:46 2023 -0400
Commit: Noel Grandin <noel.gran...@collabora.co.uk>
CommitDate: Fri Jul 21 10:14:19 2023 +0200
tdf#156361 use slow blending path if alpha mask blending is diabled
SkiaSalGraphicsImpl::blendBitmap() fails unexpectedly in the following
cases so return false and use the non-Skia alpha mask blending code:
- Unexpected white areas when running a slideshow or printing:
https://bugs.documentfoundation.org/attachment.cgi?id=188447
- Unexpected scaling of bitmap and/or alpha mask when exporting to PDF:
https://bugs.documentfoundation.org/attachment.cgi?id=188498
Change-Id: I13ae613f24bff4cd018110a08ed70559a1714687
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/154690
Reviewed-by: Patrick Luby <plub...@neooffice.org>
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.gran...@collabora.co.uk>
diff --git a/include/vcl/skia/SkiaHelper.hxx b/include/vcl/skia/SkiaHelper.hxx
index 37fed7ff4de9..769c4d27a9ac 100644
--- a/include/vcl/skia/SkiaHelper.hxx
+++ b/include/vcl/skia/SkiaHelper.hxx
@@ -19,6 +19,7 @@ namespace SkiaHelper
{
VCL_DLLPUBLIC bool isVCLSkiaEnabled();
VCL_DLLPUBLIC OUString readLog();
+VCL_DLLPUBLIC bool isAlphaMaskBlendingEnabled();
#if HAVE_FEATURE_SKIA
diff --git a/vcl/skia/SkiaHelper.cxx b/vcl/skia/SkiaHelper.cxx
index 16cbdd306fd1..9875b7846631 100644
--- a/vcl/skia/SkiaHelper.cxx
+++ b/vcl/skia/SkiaHelper.cxx
@@ -18,6 +18,7 @@
namespace SkiaHelper
{
bool isVCLSkiaEnabled() { return false; }
+bool isAlphaMaskBlendingEnabled() { return false; }
} // namespace
@@ -369,6 +370,8 @@ bool isVCLSkiaEnabled()
return bRet;
}
+bool isAlphaMaskBlendingEnabled() { return false; }
+
static RenderMethod methodToUse = RenderRaster;
static bool initRenderMethodToUse()
diff --git a/vcl/skia/gdiimpl.cxx b/vcl/skia/gdiimpl.cxx
index cc823e4ccdd4..7145644b01eb 100644
--- a/vcl/skia/gdiimpl.cxx
+++ b/vcl/skia/gdiimpl.cxx
@@ -1297,6 +1297,16 @@ bool SkiaSalGraphicsImpl::blendAlphaBitmap(const
SalTwoRect& rPosAry,
const SalBitmap& rMaskBitmap,
const SalBitmap& rAlphaBitmap)
{
+ // tdf#156361 use slow blending path if alpha mask blending is diabled
+ // SkiaSalGraphicsImpl::blendBitmap() fails unexpectedly in the following
+ // cases so return false and use the non-Skia alpha mask blending code:
+ // - Unexpected white areas when running a slideshow or printing:
+ // https://bugs.documentfoundation.org/attachment.cgi?id=188447
+ // - Unexpected scaling of bitmap and/or alpha mask when exporting to PDF:
+ // https://bugs.documentfoundation.org/attachment.cgi?id=188498
+ if (!SkiaHelper::isAlphaMaskBlendingEnabled())
+ return false;
+
if (checkInvalidSourceOrDestination(rPosAry))
return false;
diff --git a/vcl/source/outdev/bitmap.cxx b/vcl/source/outdev/bitmap.cxx
index 8e453e835904..90f8271b544c 100644
--- a/vcl/source/outdev/bitmap.cxx
+++ b/vcl/source/outdev/bitmap.cxx
@@ -358,7 +358,7 @@ void OutputDevice::DrawDeviceAlphaBitmap( const Bitmap&
rBmp, const AlphaMask& r
// we need to make sure Skia never reaches this slow code path
// (but do not fail in no-op cases)
- assert(!SkiaHelper::isVCLSkiaEnabled()
+ assert(!SkiaHelper::isVCLSkiaEnabled() ||
!SkiaHelper::isAlphaMaskBlendingEnabled()
|| tools::Rectangle(Point(), rBmp.GetSizePixel())
.Intersection(tools::Rectangle(rSrcPtPixel,
rSrcSizePixel)).IsEmpty()
||
mpAlphaVDev->LogicToPixel(mpAlphaVDev->GetOutputSizePixel()).IsEmpty());
