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
  30 using namespace SkiaHelper;
  31
  32 namespace SkiaHelper
  33 {
  34 CGImageRef createCGImage(const Image& rImage)
  35 {
  36     BitmapEx bitmapEx(rImage.GetBitmapEx());
  37     Bitmap bitmap(bitmapEx.GetBitmap());
  38
  39     if (bitmap.IsEmpty() || !bitmap.ImplGetSalBitmap())
  40         return nullptr;
  41
  42     assert(dynamic_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get()) != nullptr);
  43     SkiaSalBitmap* skiaBitmap = static_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get());
  44
  45     SkBitmap targetBitmap;
  46     if (!targetBitmap.tryAllocPixels(
  47             SkImageInfo::Make(bitmap.GetSizePixel().getWidth(), bitmap.GetSizePixel().getHeight(),
  48                               kRGBA_8888_SkColorType, kPremul_SkAlphaType)))
  49         return nullptr;
  50     SkPaint paint;
  51     paint.setBlendMode(SkBlendMode::kSrc); // set as is
  52     SkMatrix matrix; // The image is needed upside-down.
  53     matrix.preTranslate(0, targetBitmap.height());
  54     matrix.setConcat(matrix, SkMatrix::Scale(1, -1));
  55
  56     if (!bitmapEx.IsAlpha())
  57     {
  58         SkCanvas canvas(targetBitmap);
  59         canvas.concat(matrix);
  60         canvas.drawImage(skiaBitmap->GetSkImage(), 0, 0, SkSamplingOptions(), &paint);
  61     }
  62     else
  63     {
  64         AlphaMask alpha(bitmapEx.GetAlpha());
  65         Bitmap alphaBitmap(alpha.GetBitmap());
  66         assert(dynamic_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get()) != nullptr);
  67         SkiaSalBitmap* skiaAlpha
  68             = static_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get());
  69 #if 0
  70         // Drawing to a bitmap using a shader from a GPU-backed image fails silently.
  71         // https://bugs.chromium.org/p/skia/issues/detail?id=12685
  72         paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut,
  73                                          skiaBitmap->GetSkShader(SkSamplingOptions()),
  74                                          skiaAlpha->GetAlphaSkShader(SkSamplingOptions())));
  75 #else
  76         sk_sp<SkImage> imB = skiaBitmap->GetSkImage()->makeNonTextureImage();
  77         sk_sp<SkImage> imA = skiaAlpha->GetAlphaSkImage()->makeNonTextureImage();
  78         paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut, imB->makeShader(SkSamplingOptions()),
  79                                          imA->makeShader(SkSamplingOptions())));
  80 #endif
  81         SkCanvas canvas(targetBitmap);
  82         canvas.concat(matrix);
  83         canvas.drawPaint(paint);
  84     }
  85
  86     CGContextRef context = CGBitmapContextCreate(
  87         targetBitmap.getAddr32(0, 0), targetBitmap.width(), targetBitmap.height(), 8,
  88         targetBitmap.rowBytes(), GetSalData()->mxRGBSpace, kCGImageAlphaPremultipliedLast);
  89     if (!context)
  90         return nullptr;
  91     CGImageRef screenImage = CGBitmapContextCreateImage(context);
  92     CFRelease(context);
  93     return screenImage;
  94 }
  95 }
  96
  97 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */