vcl/skia/osx/bitmap.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * Some of this code is based on Skia source code, covered by the following
  10  * license notice (see readlicense_oo for the full license):
  11  *
  12  * Copyright 2016 Google Inc.
  13  *
  14  * Use of this source code is governed by a BSD-style license that can be
  15  * found in the LICENSE file.
  16  *
  17  */
  18
  19 #include <skia/osx/bitmap.hxx>
  20
  21 #include <vcl/bitmapex.hxx>
  22 #include <vcl/image.hxx>
  23
  24 #include <skia/salbmp.hxx>
  25 #include <osx/saldata.hxx>
  26
  27 #include <SkBitmap.h>
  28 #include <SkCanvas.h>
  29 #include <SkShader.h>
  30
  31 using namespace SkiaHelper;
  32
  33 namespace SkiaHelper
  34 {
  35 CGImageRef createCGImage(const Image& rImage)
  36 {
  37     BitmapEx bitmapEx(rImage.GetBitmapEx());
  38     Bitmap bitmap(bitmapEx.GetBitmap());
  39
  40     if (bitmap.IsEmpty() || !bitmap.ImplGetSalBitmap())
  41         return nullptr;
  42
  43     assert(dynamic_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get()) != nullptr);
  44     SkiaSalBitmap* skiaBitmap = static_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get());
  45
  46     SkBitmap targetBitmap;
  47     if (!targetBitmap.tryAllocPixels(
  48             SkImageInfo::Make(bitmap.GetSizePixel().getWidth(), bitmap.GetSizePixel().getHeight(),
  49                               kRGBA_8888_SkColorType, kPremul_SkAlphaType)))
  50         return nullptr;
  51     SkPaint paint;
  52     paint.setBlendMode(SkBlendMode::kSrc); // set as is
  53     SkMatrix matrix; // The image is needed upside-down.
  54     matrix.preTranslate(0, targetBitmap.height());
  55     matrix.setConcat(matrix, SkMatrix::Scale(1, -1));
  56
  57     if (!bitmapEx.IsAlpha())
  58     {
  59         SkCanvas canvas(targetBitmap);
  60         canvas.concat(matrix);
  61         canvas.drawImage(skiaBitmap->GetSkImage(), 0, 0, SkSamplingOptions(), &paint);
  62     }
  63     else
  64     {
  65         AlphaMask alpha(bitmapEx.GetAlphaMask());
  66         // tdf#156854 invert alpha mask for macOS native menu item images
  67         // At the time of this change, only the AquaSalMenu class calls this
  68         // function so it should be safe to invert the alpha mask here.
  69         alpha.Invert();
  70         Bitmap alphaBitmap(alpha.GetBitmap());
  71         assert(dynamic_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get()) != nullptr);
  72         SkiaSalBitmap* skiaAlpha
  73             = static_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get());
  74 #if 0
  75         // Drawing to a bitmap using a shader from a GPU-backed image fails silently.
  76         // https://bugs.chromium.org/p/skia/issues/detail?id=12685
  77         paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut,
  78                                          skiaBitmap->GetSkShader(SkSamplingOptions()),
  79                                          skiaAlpha->GetAlphaSkShader(SkSamplingOptions())));
  80 #else
  81         sk_sp<SkImage> imB = skiaBitmap->GetSkImage()->makeNonTextureImage();
  82         sk_sp<SkImage> imA = skiaAlpha->GetAlphaSkImage()->makeNonTextureImage();
  83         paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut, imB->makeShader(SkSamplingOptions()),
  84                                          imA->makeShader(SkSamplingOptions())));
  85 #endif
  86         SkCanvas canvas(targetBitmap);
  87         canvas.concat(matrix);
  88         canvas.drawPaint(paint);
  89     }
  90
  91     CGContextRef context = CGBitmapContextCreate(
  92         targetBitmap.getAddr32(0, 0), targetBitmap.width(), targetBitmap.height(), 8,
  93         targetBitmap.rowBytes(), GetSalData()->mxRGBSpace, kCGImageAlphaPremultipliedLast);
  94     if (!context)
  95         return nullptr;
  96     CGImageRef screenImage = CGBitmapContextCreateImage(context);
  97     CFRelease(context);
  98     return screenImage;
  99 }
 100 }
 101
 102 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */