blob: 5a672aa921a286e3ebc4b6170ef481a189e21c59 [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "ui/base/cursor/cursor_util.h"
#include "base/logging.h"
#include "skia/ext/image_operations.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/gfx/geometry/point_conversions.h"
#include "ui/gfx/geometry/size_conversions.h"
#include "ui/gfx/image/image_skia.h"
#include "ui/gfx/skbitmap_operations.h"
#include "ui/gfx/skia_util.h"
namespace ui {
namespace {
// Converts the SkBitmap to use a different alpha type. Returns true if bitmap
// was modified, otherwise returns false.
bool ConvertSkBitmapAlphaType(SkBitmap* bitmap, SkAlphaType alpha_type) {
if (bitmap->info().alphaType() == alpha_type) {
return false;
// Copy the bitmap into a temporary buffer. This will convert alpha type.
SkImageInfo image_info =
SkImageInfo::MakeN32(bitmap->width(), bitmap->height(), alpha_type);
size_t info_row_bytes = image_info.minRowBytes();
std::vector<char> buffer(image_info.computeByteSize(info_row_bytes));
bitmap->readPixels(image_info, &buffer[0], info_row_bytes, 0, 0);
// Read the temporary buffer back into the original bitmap.
// this memcpy call assumes bitmap->rowBytes() == info_row_bytes
memcpy(bitmap->getPixels(), &buffer[0], buffer.size());
return true;
} // namespace
void ScaleAndRotateCursorBitmapAndHotpoint(float scale,
display::Display::Rotation rotation,
SkBitmap* bitmap,
gfx::Point* hotpoint) {
// SkBitmapOperations::Rotate() needs the bitmap to have premultiplied alpha,
// so convert bitmap alpha type if we are going to rotate.
bool was_converted = false;
if (rotation != display::Display::ROTATE_0 &&
bitmap->info().alphaType() == kUnpremul_SkAlphaType) {
ConvertSkBitmapAlphaType(bitmap, kPremul_SkAlphaType);
was_converted = true;
switch (rotation) {
case display::Display::ROTATE_0:
case display::Display::ROTATE_90:
hotpoint->SetPoint(bitmap->height() - hotpoint->y(), hotpoint->x());
*bitmap = SkBitmapOperations::Rotate(
*bitmap, SkBitmapOperations::ROTATION_90_CW);
case display::Display::ROTATE_180:
bitmap->width() - hotpoint->x(), bitmap->height() - hotpoint->y());
*bitmap = SkBitmapOperations::Rotate(
*bitmap, SkBitmapOperations::ROTATION_180_CW);
case display::Display::ROTATE_270:
hotpoint->SetPoint(hotpoint->y(), bitmap->width() - hotpoint->x());
*bitmap = SkBitmapOperations::Rotate(
*bitmap, SkBitmapOperations::ROTATION_270_CW);
if (was_converted) {
ConvertSkBitmapAlphaType(bitmap, kUnpremul_SkAlphaType);
if (scale < FLT_EPSILON) {
NOTREACHED() << "Scale must be larger than 0.";
scale = 1.0f;
if (scale == 1.0f)
gfx::Size scaled_size = gfx::ScaleToFlooredSize(
gfx::Size(bitmap->width(), bitmap->height()), scale);
*bitmap = skia::ImageOperations::Resize(
*hotpoint = gfx::ScaleToFlooredPoint(*hotpoint, scale);
void GetImageCursorBitmap(int resource_id,
float scale,
display::Display::Rotation rotation,
gfx::Point* hotspot,
SkBitmap* bitmap) {
const gfx::ImageSkia* image =
const gfx::ImageSkiaRep& image_rep = image->GetRepresentation(scale);
// TODO(oshima): The cursor should use resource scale factor when
// fractional scale factor is enabled.
(*bitmap) = image_rep.sk_bitmap();
scale / image_rep.scale(), rotation, bitmap, hotspot);
// |image_rep| is owned by the resource bundle. So we do not need to free it.
void GetAnimatedCursorBitmaps(int resource_id,
float scale,
display::Display::Rotation rotation,
gfx::Point* hotspot,
std::vector<SkBitmap>* bitmaps) {
// TODO(oshima|tdanderson): Support rotation and fractional scale factor.
const gfx::ImageSkia* image =
const gfx::ImageSkiaRep& image_rep = image->GetRepresentation(scale);
SkBitmap bitmap = image_rep.sk_bitmap();
int frame_width = bitmap.height();
int frame_height = frame_width;
int total_width = bitmap.width();
DCHECK_EQ(total_width % frame_width, 0);
int frame_count = total_width / frame_width;
DCHECK_GT(frame_count, 0);
for (int frame = 0; frame < frame_count; ++frame) {
int x_offset = frame_width * frame;
DCHECK_LE(x_offset + frame_width, total_width);
SkBitmap cropped = SkBitmapOperations::CreateTiledBitmap(
bitmap, x_offset, 0, frame_width, frame_height);
DCHECK_EQ(frame_width, cropped.width());
DCHECK_EQ(frame_height, cropped.height());
(*bitmaps)[frame] = cropped;
} // namespace ui