vcl/inc/skia/gdiimpl.hxx | 11 +++++++++++
vcl/inc/skia/utils.hxx | 26 +++++++++++++++++---------
vcl/skia/gdiimpl.cxx | 10 +++++-----
3 files changed, 33 insertions(+), 14 deletions(-)
New commits:
commit 60b195cd41f93fc24bfb7897bde20ac3cbeadd1f
Author: Luboš Luňák <l.lu...@collabora.com>
AuthorDate: Fri Dec 3 16:48:47 2021 +0100
Commit: Luboš Luňák <l.lu...@collabora.com>
CommitDate: Sat Dec 4 13:27:08 2021 +0100
only bilinear+mipmap for Skia/raster to-screen drawing (tdf#146024)
The code already tries to hide the cost of the high-quality bicubic
scaling by caching, but there are still cases where there's too
much scaling done. Since this is only drawing to screen, use
only bilinear+mipmap scaling in raster mode, which should be good
enough (it's what the "super" scaling VCL algorithm for
BmpScaleFlag::Default does as well).
Change-Id: I75c86932e097411422dc1ef5e0534059dbf11ff8
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/126326
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lu...@collabora.com>
(cherry picked from commit 0a596fbd94e1750e9d1f5cdab624c719b33c3ab4)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/126296
diff --git a/vcl/inc/skia/gdiimpl.hxx b/vcl/inc/skia/gdiimpl.hxx
index cc4cda4b2ebd..449240623271 100644
--- a/vcl/inc/skia/gdiimpl.hxx
+++ b/vcl/inc/skia/gdiimpl.hxx
@@ -308,6 +308,17 @@ protected:
void performDrawPolyPolygon(const basegfx::B2DPolyPolygon& polygon, double
transparency,
bool useAA);
+ BmpScaleFlag goodScalingQuality() const { return
SkiaHelper::goodScalingQuality(isGPU()); }
+ SkSamplingOptions makeSamplingOptions(const SalTwoRect& rPosAry, int
scalingFactor,
+ int srcScalingFactor = 1)
+ {
+ return SkiaHelper::makeSamplingOptions(rPosAry, scalingFactor,
srcScalingFactor, isGPU());
+ }
+ SkSamplingOptions makeSamplingOptions(const SkMatrix& matrix, int
scalingFactor)
+ {
+ return SkiaHelper::makeSamplingOptions(goodScalingQuality(), matrix,
scalingFactor);
+ }
+
// Create SkPaint set up for drawing lines (using mLineColor etc.).
SkPaint makeLinePaint(double transparency = 0) const
{
diff --git a/vcl/inc/skia/utils.hxx b/vcl/inc/skia/utils.hxx
index 0583e9ceb624..1a5993bef2d3 100644
--- a/vcl/inc/skia/utils.hxx
+++ b/vcl/inc/skia/utils.hxx
@@ -133,6 +133,16 @@ inline bool isUnitTestRunning(const char* name = nullptr)
return testname != nullptr && std::string_view(name) == testname;
}
+// Scaling done on the GPU is fast, but bicubic done in raster mode can be slow
+// if done too much, and it generally shouldn't be needed for to-screen
drawing.
+// In that case use only BmpScaleFlag::Default, which is bilinear+mipmap,
+// which should be good enough (and that's what the "super" bitmap scaling
+// algorithm done by VCL does as well).
+inline BmpScaleFlag goodScalingQuality(bool isGPU)
+{
+ return isGPU ? BmpScaleFlag::BestQuality : BmpScaleFlag::Default;
+}
+
// Normal scaling algorithms have a poor quality when downscaling a lot.
// https://bugs.chromium.org/p/skia/issues/detail?id=11810 suggests to use
mipmaps
// in such a case, which is annoying to do explicitly instead of Skia deciding
which
@@ -154,7 +164,9 @@ inline SkSamplingOptions makeSamplingOptions(BmpScaleFlag
scalingType, SkMatrix
return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kLinear);
return SkSamplingOptions(SkCubicResampler::Mitchell());
case BmpScaleFlag::Default:
- return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kNone);
+ // Use SkMipmapMode::kNearest for better quality when downscaling.
SkMipmapMode::kLinear
+ // would be even better, but it is not specially optimized in
raster mode.
+ return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kNearest);
case BmpScaleFlag::Fast:
case BmpScaleFlag::NearestNeighbor:
return SkSamplingOptions(SkFilterMode::kNearest,
SkMipmapMode::kNone);
@@ -177,7 +189,8 @@ inline SkSamplingOptions makeSamplingOptions(BmpScaleFlag
scalingType, const Siz
return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kLinear);
return SkSamplingOptions(SkCubicResampler::Mitchell());
case BmpScaleFlag::Default:
- return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kNone);
+ // As in the first overload, use kNearest.
+ return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kNearest);
case BmpScaleFlag::Fast:
case BmpScaleFlag::NearestNeighbor:
return SkSamplingOptions(SkFilterMode::kNearest,
SkMipmapMode::kNone);
@@ -188,7 +201,7 @@ inline SkSamplingOptions makeSamplingOptions(BmpScaleFlag
scalingType, const Siz
}
inline SkSamplingOptions makeSamplingOptions(const SalTwoRect& rPosAry, int
scalingFactor,
- int srcScalingFactor = 1)
+ int srcScalingFactor, bool isGPU)
{
// If there will be scaling, make it smooth, but not in unittests, as
those often
// require exact color values and would be confused by this.
@@ -201,12 +214,7 @@ inline SkSamplingOptions makeSamplingOptions(const
SalTwoRect& rPosAry, int scal
if (srcScalingFactor != 1)
srcSize *= srcScalingFactor;
if (srcSize != destSize)
- {
- if (srcSize.Width() / destSize.Width() >= downscaleRatioThreshold
- || srcSize.Height() / destSize.Height() >= downscaleRatioThreshold)
- return SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kLinear);
- return SkSamplingOptions(SkCubicResampler::Mitchell()); // best
- }
+ return makeSamplingOptions(goodScalingQuality(isGPU), srcSize,
destSize, 1);
return SkSamplingOptions(); // none
}
diff --git a/vcl/skia/gdiimpl.cxx b/vcl/skia/gdiimpl.cxx
index bab66a93c63e..6bb770d51ba0 100644
--- a/vcl/skia/gdiimpl.cxx
+++ b/vcl/skia/gdiimpl.cxx
@@ -1487,7 +1487,7 @@ std::shared_ptr<SalBitmap>
SkiaSalGraphicsImpl::getBitmap(tools::Long nX, tools:
if (mScaling != 1)
{
if (!isUnitTestRunning())
- bitmap->Scale(1.0 / mScaling, 1.0 / mScaling,
BmpScaleFlag::BestQuality);
+ bitmap->Scale(1.0 / mScaling, 1.0 / mScaling,
goodScalingQuality());
else
{
// Some tests require exact pixel values and would be confused by
smooth-scaling.
@@ -1495,7 +1495,7 @@ std::shared_ptr<SalBitmap>
SkiaSalGraphicsImpl::getBitmap(tools::Long nX, tools:
if
(isUnitTestRunning("BackendTest__testDrawHaflEllipseAAWithPolyLineB2D_")
|| isUnitTestRunning("BackendTest__testDrawRectAAWithLine_"))
{
- bitmap->Scale(1.0 / mScaling, 1.0 / mScaling,
BmpScaleFlag::BestQuality);
+ bitmap->Scale(1.0 / mScaling, 1.0 / mScaling,
goodScalingQuality());
}
else
bitmap->Scale(1.0 / mScaling, 1.0 / mScaling,
BmpScaleFlag::NearestNeighbor);
@@ -1760,7 +1760,7 @@ sk_sp<SkImage>
SkiaSalGraphicsImpl::mergeCacheBitmaps(const SkiaSalBitmap& bitma
matrix.set(SkMatrix::kMScaleY, 1.0 * targetSize.Height() /
sourceSize.Height());
canvas->concat(matrix);
if (!isUnitTestRunning()) // unittests want exact pixel values
- samplingOptions = makeSamplingOptions(BmpScaleFlag::BestQuality,
matrix, 1);
+ samplingOptions = makeSamplingOptions(matrix, 1);
}
if (alphaBitmap != nullptr)
{
@@ -2011,7 +2011,7 @@ bool SkiaSalGraphicsImpl::drawTransformedBitmap(const
basegfx::B2DPoint& rNull,
// If the matrix changes geometry, we need to smooth-scale. If there's
mScaling,
// that's already been handled by mergeCacheBitmaps().
if (matrixNeedsHighQuality(matrix))
- samplingOptions = makeSamplingOptions(BmpScaleFlag::BestQuality,
matrix, 1);
+ samplingOptions = makeSamplingOptions(matrix, 1);
if (fAlpha == 1.0)
{
// Specify sizes to scale the image size back if needed (because
of mScaling).
@@ -2046,7 +2046,7 @@ bool SkiaSalGraphicsImpl::drawTransformedBitmap(const
basegfx::B2DPoint& rNull,
canvas->concat(matrix);
SkSamplingOptions samplingOptions;
if (matrixNeedsHighQuality(matrix) || (mScaling != 1 &&
!isUnitTestRunning()))
- samplingOptions = makeSamplingOptions(BmpScaleFlag::BestQuality,
matrix, mScaling);
+ samplingOptions = makeSamplingOptions(matrix, mScaling);
if (pSkiaAlphaBitmap)
{
SkPaint paint;
