ui/gfx/skia_util.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/gfx/skia_util.h"
   6
   7 #include "third_party/skia/include/core/SkBitmap.h"
   8 #include "third_party/skia/include/core/SkColorFilter.h"
   9 #include "third_party/skia/include/core/SkColorPriv.h"
  10 #include "third_party/skia/include/core/SkUnPreMultiply.h"
  11 #include "third_party/skia/include/effects/SkBlurMaskFilter.h"
  12 #include "third_party/skia/include/effects/SkGradientShader.h"
  13 #include "third_party/skia/include/effects/SkLayerDrawLooper.h"
  14 #include "ui/gfx/image/image_skia_rep.h"
  15 #include "ui/gfx/rect.h"
  16 #include "ui/gfx/rect_f.h"
  17 #include "ui/gfx/shadow_value.h"
  18
  19 namespace gfx {
  20
  21 SkRect RectToSkRect(const Rect& rect) {
  22   SkRect r;
  23   r.iset(rect.x(), rect.y(), rect.right(), rect.bottom());
  24   return r;
  25 }
  26
  27 SkIRect RectToSkIRect(const Rect& rect) {
  28   return SkIRect::MakeXYWH(rect.x(), rect.y(), rect.width(), rect.height());
  29 }
  30
  31 Rect SkIRectToRect(const SkIRect& rect) {
  32   return Rect(rect.x(), rect.y(), rect.width(), rect.height());
  33 }
  34
  35 SkRect RectFToSkRect(const RectF& rect) {
  36   return SkRect::MakeXYWH(SkFloatToScalar(rect.x()),
  37                           SkFloatToScalar(rect.y()),
  38                           SkFloatToScalar(rect.width()),
  39                           SkFloatToScalar(rect.height()));
  40 }
  41
  42 RectF SkRectToRectF(const SkRect& rect) {
  43   return RectF(SkScalarToFloat(rect.x()),
  44                SkScalarToFloat(rect.y()),
  45                SkScalarToFloat(rect.width()),
  46                SkScalarToFloat(rect.height()));
  47 }
  48
  49
  50 skia::RefPtr<SkShader> CreateImageRepShader(const gfx::ImageSkiaRep& image_rep,
  51                                             SkShader::TileMode tile_mode,
  52                                             const SkMatrix& local_matrix) {
  53   skia::RefPtr<SkShader> shader = skia::AdoptRef(SkShader::CreateBitmapShader(
  54       image_rep.sk_bitmap(), tile_mode, tile_mode));
  55   SkScalar scale_x = local_matrix.getScaleX();
  56   SkScalar scale_y = local_matrix.getScaleY();
  57   SkScalar bitmap_scale = SkFloatToScalar(image_rep.GetScale());
  58
  59   // Unscale matrix by |bitmap_scale| such that the bitmap is drawn at the
  60   // correct density.
  61   // Convert skew and translation to pixel coordinates.
  62   // Thus, for |bitmap_scale| = 2:
  63   //   x scale = 2, x translation = 1 DIP,
  64   // should be converted to
  65   //   x scale = 1, x translation = 2 pixels.
  66   SkMatrix shader_scale = local_matrix;
  67   shader_scale.preScale(bitmap_scale, bitmap_scale);
  68   shader_scale.setScaleX(SkScalarDiv(scale_x, bitmap_scale));
  69   shader_scale.setScaleY(SkScalarDiv(scale_y, bitmap_scale));
  70
  71   shader->setLocalMatrix(shader_scale);
  72   return shader;
  73 }
  74
  75 skia::RefPtr<SkShader> CreateGradientShader(int start_point,
  76                                             int end_point,
  77                                             SkColor start_color,
  78                                             SkColor end_color) {
  79   SkColor grad_colors[2] = { start_color, end_color};
  80   SkPoint grad_points[2];
  81   grad_points[0].iset(0, start_point);
  82   grad_points[1].iset(0, end_point);
  83
  84   return skia::AdoptRef(SkGradientShader::CreateLinear(
  85       grad_points, grad_colors, NULL, 2, SkShader::kRepeat_TileMode));
  86 }
  87
  88 skia::RefPtr<SkDrawLooper> CreateShadowDrawLooper(
  89     const std::vector<ShadowValue>& shadows) {
  90   if (shadows.empty())
  91     return skia::RefPtr<SkDrawLooper>();
  92
  93   skia::RefPtr<SkLayerDrawLooper> looper =
  94       skia::AdoptRef(new SkLayerDrawLooper);
  95
  96   looper->addLayer();  // top layer of the original.
  97
  98   SkLayerDrawLooper::LayerInfo layer_info;
  99   layer_info.fPaintBits |= SkLayerDrawLooper::kMaskFilter_Bit;
 100   layer_info.fPaintBits |= SkLayerDrawLooper::kColorFilter_Bit;
 101   layer_info.fColorMode = SkXfermode::kSrc_Mode;
 102
 103   for (size_t i = 0; i < shadows.size(); ++i) {
 104     const ShadowValue& shadow = shadows[i];
 105
 106     layer_info.fOffset.set(SkIntToScalar(shadow.x()),
 107                            SkIntToScalar(shadow.y()));
 108
 109     // SkBlurMaskFilter's blur radius defines the range to extend the blur from
 110     // original mask, which is half of blur amount as defined in ShadowValue.
 111     skia::RefPtr<SkMaskFilter> blur_mask = skia::AdoptRef(
 112         SkBlurMaskFilter::Create(SkDoubleToScalar(shadow.blur() / 2),
 113                                  SkBlurMaskFilter::kNormal_BlurStyle,
 114                                  SkBlurMaskFilter::kHighQuality_BlurFlag));
 115     skia::RefPtr<SkColorFilter> color_filter = skia::AdoptRef(
 116         SkColorFilter::CreateModeFilter(shadow.color(),
 117                                         SkXfermode::kSrcIn_Mode));
 118
 119     SkPaint* paint = looper->addLayer(layer_info);
 120     paint->setMaskFilter(blur_mask.get());
 121     paint->setColorFilter(color_filter.get());
 122   }
 123
 124   return looper;
 125 }
 126
 127 bool BitmapsAreEqual(const SkBitmap& bitmap1, const SkBitmap& bitmap2) {
 128   void* addr1 = NULL;
 129   void* addr2 = NULL;
 130   size_t size1 = 0;
 131   size_t size2 = 0;
 132
 133   bitmap1.lockPixels();
 134   addr1 = bitmap1.getAddr32(0, 0);
 135   size1 = bitmap1.getSize();
 136   bitmap1.unlockPixels();
 137
 138   bitmap2.lockPixels();
 139   addr2 = bitmap2.getAddr32(0, 0);
 140   size2 = bitmap2.getSize();
 141   bitmap2.unlockPixels();
 142
 143   return (size1 == size2) && (0 == memcmp(addr1, addr2, bitmap1.getSize()));
 144 }
 145
 146 void ConvertSkiaToRGBA(const unsigned char* skia,
 147                        int pixel_width,
 148                        unsigned char* rgba) {
 149   int total_length = pixel_width * 4;
 150   for (int i = 0; i < total_length; i += 4) {
 151     const uint32_t pixel_in = *reinterpret_cast<const uint32_t*>(&skia[i]);
 152
 153     // Pack the components here.
 154     int alpha = SkGetPackedA32(pixel_in);
 155     if (alpha != 0 && alpha != 255) {
 156       SkColor unmultiplied = SkUnPreMultiply::PMColorToColor(pixel_in);
 157       rgba[i + 0] = SkColorGetR(unmultiplied);
 158       rgba[i + 1] = SkColorGetG(unmultiplied);
 159       rgba[i + 2] = SkColorGetB(unmultiplied);
 160       rgba[i + 3] = alpha;
 161     } else {
 162       rgba[i + 0] = SkGetPackedR32(pixel_in);
 163       rgba[i + 1] = SkGetPackedG32(pixel_in);
 164       rgba[i + 2] = SkGetPackedB32(pixel_in);
 165       rgba[i + 3] = alpha;
 166     }
 167   }
 168 }
 169
 170 }  // namespace gfx