1 files changed, 102 insertions, 0 deletions
diff --git a/vcl/skia/osx/bitmap.cxx b/vcl/skia/osx/bitmap.cxx
new file mode 100644
index 0000000000..edb339ce52
--- /dev/null
+++ b/vcl/skia/osx/bitmap.cxx
@@ -0,0 +1,102 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Some of this code is based on Skia source code, covered by the following
+ * license notice (see readlicense_oo for the full license):
+ *
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ */
+
+#include <skia/osx/bitmap.hxx>
+
+#include <vcl/bitmapex.hxx>
+#include <vcl/image.hxx>
+
+#include <skia/salbmp.hxx>
+#include <osx/saldata.hxx>
+
+#include <SkBitmap.h>
+#include <SkCanvas.h>
+#include <SkShader.h>
+
+using namespace SkiaHelper;
+
+namespace SkiaHelper
+{
+CGImageRef createCGImage(const Image& rImage)
+{
+    BitmapEx bitmapEx(rImage.GetBitmapEx());
+    Bitmap bitmap(bitmapEx.GetBitmap());
+
+    if (bitmap.IsEmpty() || !bitmap.ImplGetSalBitmap())
+        return nullptr;
+
+    assert(dynamic_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get()) != nullptr);
+    SkiaSalBitmap* skiaBitmap = static_cast<SkiaSalBitmap*>(bitmap.ImplGetSalBitmap().get());
+
+    SkBitmap targetBitmap;
+    if (!targetBitmap.tryAllocPixels(
+            SkImageInfo::Make(bitmap.GetSizePixel().getWidth(), bitmap.GetSizePixel().getHeight(),
+                              kRGBA_8888_SkColorType, kPremul_SkAlphaType)))
+        return nullptr;
+    SkPaint paint;
+    paint.setBlendMode(SkBlendMode::kSrc); // set as is
+    SkMatrix matrix; // The image is needed upside-down.
+    matrix.preTranslate(0, targetBitmap.height());
+    matrix.setConcat(matrix, SkMatrix::Scale(1, -1));
+
+    if (!bitmapEx.IsAlpha())
+    {
+        SkCanvas canvas(targetBitmap);
+        canvas.concat(matrix);
+        canvas.drawImage(skiaBitmap->GetSkImage(), 0, 0, SkSamplingOptions(), &paint);
+    }
+    else
+    {
+        AlphaMask alpha(bitmapEx.GetAlphaMask());
+        // tdf#156854 invert alpha mask for macOS native menu item images
+        // At the time of this change, only the AquaSalMenu class calls this
+        // function so it should be safe to invert the alpha mask here.
+        alpha.Invert();
+        Bitmap alphaBitmap(alpha.GetBitmap());
+        assert(dynamic_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get()) != nullptr);
+        SkiaSalBitmap* skiaAlpha
+            = static_cast<SkiaSalBitmap*>(alphaBitmap.ImplGetSalBitmap().get());
+#if 0
+        // Drawing to a bitmap using a shader from a GPU-backed image fails silently.
+        // https://bugs.chromium.org/p/skia/issues/detail?id=12685
+        paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut,
+                                         skiaBitmap->GetSkShader(SkSamplingOptions()),
+                                         skiaAlpha->GetAlphaSkShader(SkSamplingOptions())));
+#else
+        sk_sp<SkImage> imB = skiaBitmap->GetSkImage()->makeNonTextureImage();
+        sk_sp<SkImage> imA = skiaAlpha->GetAlphaSkImage()->makeNonTextureImage();
+        paint.setShader(SkShaders::Blend(SkBlendMode::kDstOut, imB->makeShader(SkSamplingOptions()),
+                                         imA->makeShader(SkSamplingOptions())));
+#endif
+        SkCanvas canvas(targetBitmap);
+        canvas.concat(matrix);
+        canvas.drawPaint(paint);
+    }
+
+    CGContextRef context = CGBitmapContextCreate(
+        targetBitmap.getAddr32(0, 0), targetBitmap.width(), targetBitmap.height(), 8,
+        targetBitmap.rowBytes(), GetSalData()->mxRGBSpace, kCGImageAlphaPremultipliedLast);
+    if (!context)
+        return nullptr;
+    CGImageRef screenImage = CGBitmapContextCreateImage(context);
+    CFRelease(context);
+    return screenImage;
+}
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */