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      1 // Copyright 2014 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/base/cursor/cursor_util.h"
      6 
      7 #include "base/logging.h"
      8 #include "skia/ext/image_operations.h"
      9 #include "ui/base/resource/resource_bundle.h"
     10 #include "ui/gfx/image/image_skia.h"
     11 #include "ui/gfx/point_conversions.h"
     12 #include "ui/gfx/size_conversions.h"
     13 #include "ui/gfx/skbitmap_operations.h"
     14 #include "ui/gfx/skia_util.h"
     15 
     16 namespace ui {
     17 
     18 void ScaleAndRotateCursorBitmapAndHotpoint(float scale,
     19                                            gfx::Display::Rotation rotation,
     20                                            SkBitmap* bitmap,
     21                                            gfx::Point* hotpoint) {
     22   switch (rotation) {
     23     case gfx::Display::ROTATE_0:
     24       break;
     25     case gfx::Display::ROTATE_90:
     26       hotpoint->SetPoint(bitmap->height() - hotpoint->y(), hotpoint->x());
     27       *bitmap = SkBitmapOperations::Rotate(
     28           *bitmap, SkBitmapOperations::ROTATION_90_CW);
     29       break;
     30     case gfx::Display::ROTATE_180:
     31       hotpoint->SetPoint(
     32           bitmap->width() - hotpoint->x(), bitmap->height() - hotpoint->y());
     33       *bitmap = SkBitmapOperations::Rotate(
     34           *bitmap, SkBitmapOperations::ROTATION_180_CW);
     35       break;
     36     case gfx::Display::ROTATE_270:
     37       hotpoint->SetPoint(hotpoint->y(), bitmap->width() - hotpoint->x());
     38       *bitmap = SkBitmapOperations::Rotate(
     39           *bitmap, SkBitmapOperations::ROTATION_270_CW);
     40       break;
     41   }
     42 
     43   if (scale < FLT_EPSILON) {
     44     NOTREACHED() << "Scale must be larger than 0.";
     45     scale = 1.0f;
     46   }
     47 
     48   if (scale == 1.0f)
     49     return;
     50 
     51   gfx::Size scaled_size = gfx::ToFlooredSize(
     52       gfx::ScaleSize(gfx::Size(bitmap->width(), bitmap->height()), scale));
     53 
     54   *bitmap = skia::ImageOperations::Resize(
     55       *bitmap,
     56       skia::ImageOperations::RESIZE_BETTER,
     57       scaled_size.width(),
     58       scaled_size.height());
     59   *hotpoint = gfx::ToFlooredPoint(gfx::ScalePoint(*hotpoint, scale));
     60 }
     61 
     62 void GetImageCursorBitmap(int resource_id,
     63                           float scale,
     64                           gfx::Display::Rotation rotation,
     65                           gfx::Point* hotspot,
     66                           SkBitmap* bitmap) {
     67   const gfx::ImageSkia* image =
     68       ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id);
     69   const gfx::ImageSkiaRep& image_rep = image->GetRepresentation(scale);
     70   // TODO(oshima): The cursor should use resource scale factor when
     71   // fractional scale factor is enabled. crbug.com/372212
     72   (*bitmap) = image_rep.sk_bitmap();
     73   ScaleAndRotateCursorBitmapAndHotpoint(
     74       scale / image_rep.scale(), rotation, bitmap, hotspot);
     75   // |image_rep| is owned by the resource bundle. So we do not need to free it.
     76 }
     77 
     78 void GetAnimatedCursorBitmaps(int resource_id,
     79                               float scale,
     80                               gfx::Display::Rotation rotation,
     81                               gfx::Point* hotspot,
     82                               std::vector<SkBitmap>* bitmaps) {
     83   // TODO(oshima|tdanderson): Support rotation and fractional scale factor.
     84   const gfx::ImageSkia* image =
     85       ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id);
     86   const gfx::ImageSkiaRep& image_rep = image->GetRepresentation(scale);
     87   SkBitmap bitmap = image_rep.sk_bitmap();
     88   int frame_width = bitmap.height();
     89   int frame_height = frame_width;
     90   int total_width = bitmap.width();
     91   DCHECK_EQ(total_width % frame_width, 0);
     92   int frame_count = total_width / frame_width;
     93   DCHECK_GT(frame_count, 0);
     94 
     95   bitmaps->resize(frame_count);
     96 
     97   for (int frame = 0; frame < frame_count; ++frame) {
     98     int x_offset = frame_width * frame;
     99     DCHECK_LE(x_offset + frame_width, total_width);
    100 
    101     SkBitmap cropped = SkBitmapOperations::CreateTiledBitmap(
    102         bitmap, x_offset, 0, frame_width, frame_height);
    103     DCHECK_EQ(frame_width, cropped.width());
    104     DCHECK_EQ(frame_height, cropped.height());
    105 
    106     (*bitmaps)[frame] = cropped;
    107   }
    108 }
    109 
    110 }  // namespace ui
    111