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      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 #include "ui/gfx/transform.h"
     19 
     20 namespace gfx {
     21 
     22 SkRect RectToSkRect(const Rect& rect) {
     23   SkRect r;
     24   r.iset(rect.x(), rect.y(), rect.right(), rect.bottom());
     25   return r;
     26 }
     27 
     28 SkIRect RectToSkIRect(const Rect& rect) {
     29   return SkIRect::MakeXYWH(rect.x(), rect.y(), rect.width(), rect.height());
     30 }
     31 
     32 Rect SkIRectToRect(const SkIRect& rect) {
     33   return Rect(rect.x(), rect.y(), rect.width(), rect.height());
     34 }
     35 
     36 SkRect RectFToSkRect(const RectF& rect) {
     37   return SkRect::MakeXYWH(SkFloatToScalar(rect.x()),
     38                           SkFloatToScalar(rect.y()),
     39                           SkFloatToScalar(rect.width()),
     40                           SkFloatToScalar(rect.height()));
     41 }
     42 
     43 RectF SkRectToRectF(const SkRect& rect) {
     44   return RectF(SkScalarToFloat(rect.x()),
     45                SkScalarToFloat(rect.y()),
     46                SkScalarToFloat(rect.width()),
     47                SkScalarToFloat(rect.height()));
     48 }
     49 
     50 void TransformToFlattenedSkMatrix(const gfx::Transform& transform,
     51                                   SkMatrix* flattened) {
     52   // Convert from 4x4 to 3x3 by dropping the third row and column.
     53   flattened->set(0, SkDoubleToScalar(transform.matrix().getDouble(0, 0)));
     54   flattened->set(1, SkDoubleToScalar(transform.matrix().getDouble(0, 1)));
     55   flattened->set(2, SkDoubleToScalar(transform.matrix().getDouble(0, 3)));
     56   flattened->set(3, SkDoubleToScalar(transform.matrix().getDouble(1, 0)));
     57   flattened->set(4, SkDoubleToScalar(transform.matrix().getDouble(1, 1)));
     58   flattened->set(5, SkDoubleToScalar(transform.matrix().getDouble(1, 3)));
     59   flattened->set(6, SkDoubleToScalar(transform.matrix().getDouble(3, 0)));
     60   flattened->set(7, SkDoubleToScalar(transform.matrix().getDouble(3, 1)));
     61   flattened->set(8, SkDoubleToScalar(transform.matrix().getDouble(3, 3)));
     62 }
     63 
     64 skia::RefPtr<SkShader> CreateImageRepShader(const gfx::ImageSkiaRep& image_rep,
     65                                             SkShader::TileMode tile_mode,
     66                                             const SkMatrix& local_matrix) {
     67   skia::RefPtr<SkShader> shader = skia::AdoptRef(SkShader::CreateBitmapShader(
     68       image_rep.sk_bitmap(), tile_mode, tile_mode));
     69   SkScalar scale_x = local_matrix.getScaleX();
     70   SkScalar scale_y = local_matrix.getScaleY();
     71   SkScalar bitmap_scale = SkFloatToScalar(image_rep.GetScale());
     72 
     73   // Unscale matrix by |bitmap_scale| such that the bitmap is drawn at the
     74   // correct density.
     75   // Convert skew and translation to pixel coordinates.
     76   // Thus, for |bitmap_scale| = 2:
     77   //   x scale = 2, x translation = 1 DIP,
     78   // should be converted to
     79   //   x scale = 1, x translation = 2 pixels.
     80   SkMatrix shader_scale = local_matrix;
     81   shader_scale.preScale(bitmap_scale, bitmap_scale);
     82   shader_scale.setScaleX(SkScalarDiv(scale_x, bitmap_scale));
     83   shader_scale.setScaleY(SkScalarDiv(scale_y, bitmap_scale));
     84 
     85   shader->setLocalMatrix(shader_scale);
     86   return shader;
     87 }
     88 
     89 skia::RefPtr<SkShader> CreateGradientShader(int start_point,
     90                                             int end_point,
     91                                             SkColor start_color,
     92                                             SkColor end_color) {
     93   SkColor grad_colors[2] = { start_color, end_color};
     94   SkPoint grad_points[2];
     95   grad_points[0].iset(0, start_point);
     96   grad_points[1].iset(0, end_point);
     97 
     98   return skia::AdoptRef(SkGradientShader::CreateLinear(
     99       grad_points, grad_colors, NULL, 2, SkShader::kRepeat_TileMode));
    100 }
    101 
    102 skia::RefPtr<SkDrawLooper> CreateShadowDrawLooper(
    103     const std::vector<ShadowValue>& shadows) {
    104   if (shadows.empty())
    105     return skia::RefPtr<SkDrawLooper>();
    106 
    107   skia::RefPtr<SkLayerDrawLooper> looper =
    108       skia::AdoptRef(new SkLayerDrawLooper);
    109 
    110   looper->addLayer();  // top layer of the original.
    111 
    112   SkLayerDrawLooper::LayerInfo layer_info;
    113   layer_info.fPaintBits |= SkLayerDrawLooper::kMaskFilter_Bit;
    114   layer_info.fPaintBits |= SkLayerDrawLooper::kColorFilter_Bit;
    115   layer_info.fColorMode = SkXfermode::kSrc_Mode;
    116 
    117   for (size_t i = 0; i < shadows.size(); ++i) {
    118     const ShadowValue& shadow = shadows[i];
    119 
    120     layer_info.fOffset.set(SkIntToScalar(shadow.x()),
    121                            SkIntToScalar(shadow.y()));
    122 
    123     // SkBlurMaskFilter's blur radius defines the range to extend the blur from
    124     // original mask, which is half of blur amount as defined in ShadowValue.
    125     skia::RefPtr<SkMaskFilter> blur_mask = skia::AdoptRef(
    126         SkBlurMaskFilter::Create(SkDoubleToScalar(shadow.blur() / 2),
    127                                  SkBlurMaskFilter::kNormal_BlurStyle,
    128                                  SkBlurMaskFilter::kHighQuality_BlurFlag));
    129     skia::RefPtr<SkColorFilter> color_filter = skia::AdoptRef(
    130         SkColorFilter::CreateModeFilter(shadow.color(),
    131                                         SkXfermode::kSrcIn_Mode));
    132 
    133     SkPaint* paint = looper->addLayer(layer_info);
    134     paint->setMaskFilter(blur_mask.get());
    135     paint->setColorFilter(color_filter.get());
    136   }
    137 
    138   return looper;
    139 }
    140 
    141 bool BitmapsAreEqual(const SkBitmap& bitmap1, const SkBitmap& bitmap2) {
    142   void* addr1 = NULL;
    143   void* addr2 = NULL;
    144   size_t size1 = 0;
    145   size_t size2 = 0;
    146 
    147   bitmap1.lockPixels();
    148   addr1 = bitmap1.getAddr32(0, 0);
    149   size1 = bitmap1.getSize();
    150   bitmap1.unlockPixels();
    151 
    152   bitmap2.lockPixels();
    153   addr2 = bitmap2.getAddr32(0, 0);
    154   size2 = bitmap2.getSize();
    155   bitmap2.unlockPixels();
    156 
    157   return (size1 == size2) && (0 == memcmp(addr1, addr2, bitmap1.getSize()));
    158 }
    159 
    160 void ConvertSkiaToRGBA(const unsigned char* skia,
    161                        int pixel_width,
    162                        unsigned char* rgba) {
    163   int total_length = pixel_width * 4;
    164   for (int i = 0; i < total_length; i += 4) {
    165     const uint32_t pixel_in = *reinterpret_cast<const uint32_t*>(&skia[i]);
    166 
    167     // Pack the components here.
    168     int alpha = SkGetPackedA32(pixel_in);
    169     if (alpha != 0 && alpha != 255) {
    170       SkColor unmultiplied = SkUnPreMultiply::PMColorToColor(pixel_in);
    171       rgba[i + 0] = SkColorGetR(unmultiplied);
    172       rgba[i + 1] = SkColorGetG(unmultiplied);
    173       rgba[i + 2] = SkColorGetB(unmultiplied);
    174       rgba[i + 3] = alpha;
    175     } else {
    176       rgba[i + 0] = SkGetPackedR32(pixel_in);
    177       rgba[i + 1] = SkGetPackedG32(pixel_in);
    178       rgba[i + 2] = SkGetPackedB32(pixel_in);
    179       rgba[i + 3] = alpha;
    180     }
    181   }
    182 }
    183 
    184 }  // namespace gfx
    185