third_party/WebKit/Source/platform/graphics/GraphicsContextTest.cpp

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

#include "platform/graphics/GraphicsContext.h"

#include "platform/graphics/BitmapImage.h"
#include "platform/graphics/Path.h"
#include "platform/graphics/paint/PaintController.h"
#include "platform/testing/FontTestHelpers.h"
#include "platform/testing/UnitTestHelpers.h"
#include "platform/text/TextRun.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkPicture.h"
#include "third_party/skia/include/core/SkShader.h"
#include <memory>

namespace blink {

#define EXPECT_EQ_RECT(a, b)       \
  EXPECT_EQ(a.x(), b.x());         \
  EXPECT_EQ(a.y(), b.y());         \
  EXPECT_EQ(a.width(), b.width()); \
  EXPECT_EQ(a.height(), b.height());

#define EXPECT_OPAQUE_PIXELS_IN_RECT(bitmap, opaqueRect)         \
  {                                                              \
    SkAutoLockPixels locker(bitmap);                             \
    for (int y = opaqueRect.y(); y < opaqueRect.maxY(); ++y)     \
      for (int x = opaqueRect.x(); x < opaqueRect.maxX(); ++x) { \
        int alpha = *bitmap.getAddr32(x, y) >> 24;               \
        EXPECT_EQ(255, alpha);                                   \
      }                                                          \
  }

#define EXPECT_OPAQUE_PIXELS_ONLY_IN_RECT(bitmap, opaqueRect) \
  {                                                           \
    SkAutoLockPixels locker(bitmap);                          \
    for (int y = 0; y < bitmap.height(); ++y)                 \
      for (int x = 0; x < bitmap.width(); ++x) {              \
        int alpha = *bitmap.getAddr32(x, y) >> 24;            \
        bool opaque = opaqueRect.contains(x, y);              \
        EXPECT_EQ(opaque, alpha == 255);                      \
      }                                                       \
  }

TEST(GraphicsContextTest, pictureRecording) {
  SkBitmap bitmap;
  bitmap.allocN32Pixels(100, 100);
  bitmap.eraseColor(0);
  SkCanvas canvas(bitmap);

  std::unique_ptr<PaintController> paintController = PaintController::create();
  GraphicsContext context(*paintController);

  Color opaque(1.0f, 0.0f, 0.0f, 1.0f);
  FloatRect bounds(0, 0, 100, 100);

  context.beginRecording(bounds);
  context.fillRect(FloatRect(0, 0, 50, 50), opaque, SkBlendMode::kSrcOver);
  sk_sp<const SkPicture> picture = context.endRecording();
  canvas.drawPicture(picture.get());
  EXPECT_OPAQUE_PIXELS_ONLY_IN_RECT(bitmap, IntRect(0, 0, 50, 50))

  context.beginRecording(bounds);
  context.fillRect(FloatRect(0, 0, 100, 100), opaque, SkBlendMode::kSrcOver);
  picture = context.endRecording();
  // Make sure the opaque region was unaffected by the rect drawn during Picture
  // recording.
  EXPECT_OPAQUE_PIXELS_ONLY_IN_RECT(bitmap, IntRect(0, 0, 50, 50))

  canvas.drawPicture(picture.get());
  EXPECT_OPAQUE_PIXELS_ONLY_IN_RECT(bitmap, IntRect(0, 0, 100, 100))
}

TEST(GraphicsContextTest, UnboundedDrawsAreClipped) {
  SkBitmap bitmap;
  bitmap.allocN32Pixels(400, 400);
  bitmap.eraseColor(0);
  SkCanvas canvas(bitmap);

  Color opaque(1.0f, 0.0f, 0.0f, 1.0f);
  Color alpha(0.0f, 0.0f, 0.0f, 0.0f);
  FloatRect bounds(0, 0, 100, 100);

  std::unique_ptr<PaintController> paintController = PaintController::create();
  GraphicsContext context(*paintController);
  context.beginRecording(bounds);

  context.setShouldAntialias(false);
  context.setMiterLimit(1);
  context.setStrokeThickness(5);
  context.setLineCap(SquareCap);
  context.setStrokeStyle(SolidStroke);

  // Make skia unable to compute fast bounds for our paths.
  DashArray dashArray;
  dashArray.append(1);
  dashArray.append(0);
  context.setLineDash(dashArray, 0);

  // Make the device opaque in 10,10 40x40.
  context.fillRect(FloatRect(10, 10, 40, 40), opaque, SkBlendMode::kSrcOver);
  sk_sp<const SkPicture> picture = context.endRecording();
  canvas.drawPicture(picture.get());
  EXPECT_OPAQUE_PIXELS_ONLY_IN_RECT(bitmap, IntRect(10, 10, 40, 40));

  context.beginRecording(bounds);
  // Clip to the left edge of the opaque area.
  context.clip(IntRect(10, 10, 10, 40));

  // Draw a path that gets clipped. This should destroy the opaque area, but
  // only inside the clip.
  Path path;
  path.moveTo(FloatPoint(10, 10));
  path.addLineTo(FloatPoint(40, 40));
  SkPaint paint;
  paint.setColor(alpha.rgb());
  paint.setBlendMode(SkBlendMode::kSrcOut);
  context.drawPath(path.getSkPath(), paint);

  picture = context.endRecording();
  canvas.drawPicture(picture.get());
  EXPECT_OPAQUE_PIXELS_IN_RECT(bitmap, IntRect(20, 10, 30, 40));
}

}  // namespace blink