mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
95 lines
3.8 KiB
C++
95 lines
3.8 KiB
C++
// Copyright (c) 2012 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.
|
|
|
|
#ifndef SKIA_EXT_BITMAP_PLATFORM_DEVICE_MAC_H_
|
|
#define SKIA_EXT_BITMAP_PLATFORM_DEVICE_MAC_H_
|
|
|
|
#include "base/basictypes.h"
|
|
#include "base/compiler_specific.h"
|
|
#include "skia/ext/platform_device.h"
|
|
#include "skia/ext/refptr.h"
|
|
|
|
namespace skia {
|
|
|
|
// A device is basically a wrapper around SkBitmap that provides a surface for
|
|
// SkCanvas to draw into. Our device provides a surface CoreGraphics can also
|
|
// write to. BitmapPlatformDevice creates a bitmap using
|
|
// CGCreateBitmapContext() in a format that Skia supports and can then use this
|
|
// to draw text into, etc. This pixel data is provided to the bitmap that the
|
|
// device contains so that it can be shared.
|
|
//
|
|
// The device owns the pixel data, when the device goes away, the pixel data
|
|
// also becomes invalid. THIS IS DIFFERENT THAN NORMAL SKIA which uses
|
|
// reference counting for the pixel data. In normal Skia, you could assign
|
|
// another bitmap to this device's bitmap and everything will work properly.
|
|
// For us, that other bitmap will become invalid as soon as the device becomes
|
|
// invalid, which may lead to subtle bugs. Therefore, DO NOT ASSIGN THE
|
|
// DEVICE'S PIXEL DATA TO ANOTHER BITMAP, make sure you copy instead.
|
|
class SK_API BitmapPlatformDevice : public SkBitmapDevice, public PlatformDevice {
|
|
public:
|
|
// Creates a BitmapPlatformDevice instance. |is_opaque| should be set if the
|
|
// caller knows the bitmap will be completely opaque and allows some
|
|
// optimizations.
|
|
// |context| may be NULL. If |context| is NULL, then the bitmap backing store
|
|
// is not initialized.
|
|
static BitmapPlatformDevice* Create(CGContextRef context,
|
|
int width, int height,
|
|
bool is_opaque, bool do_clear = false);
|
|
|
|
// Creates a context for |data| and calls Create.
|
|
// If |data| is NULL, then the bitmap backing store is not initialized.
|
|
static BitmapPlatformDevice* CreateWithData(uint8_t* data,
|
|
int width, int height,
|
|
bool is_opaque);
|
|
|
|
~BitmapPlatformDevice() override;
|
|
|
|
// PlatformDevice overrides
|
|
CGContextRef GetBitmapContext() override;
|
|
|
|
// SkBaseDevice overrides
|
|
void setMatrixClip(const SkMatrix& transform,
|
|
const SkRegion& region,
|
|
const SkClipStack&) override;
|
|
|
|
protected:
|
|
BitmapPlatformDevice(CGContextRef context,
|
|
const SkBitmap& bitmap);
|
|
|
|
SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) override;
|
|
|
|
private:
|
|
void ReleaseBitmapContext();
|
|
|
|
// Sets the transform and clip operations. This will not update the CGContext,
|
|
// but will mark the config as dirty. The next call of LoadConfig will
|
|
// pick up these changes.
|
|
void SetMatrixClip(const SkMatrix& transform, const SkRegion& region);
|
|
|
|
// Loads the current transform and clip into the context. Can be called even
|
|
// when |bitmap_context_| is NULL (will be a NOP).
|
|
void LoadConfig();
|
|
|
|
// Lazily-created graphics context used to draw into the bitmap.
|
|
CGContextRef bitmap_context_;
|
|
|
|
// True when there is a transform or clip that has not been set to the
|
|
// context. The context is retrieved for every text operation, and the
|
|
// transform and clip do not change as much. We can save time by not loading
|
|
// the clip and transform for every one.
|
|
bool config_dirty_;
|
|
|
|
// Translation assigned to the context: we need to keep track of this
|
|
// separately so it can be updated even if the context isn't created yet.
|
|
SkMatrix transform_;
|
|
|
|
// The current clipping
|
|
SkRegion clip_region_;
|
|
DISALLOW_COPY_AND_ASSIGN(BitmapPlatformDevice);
|
|
};
|
|
|
|
} // namespace skia
|
|
|
|
#endif // SKIA_EXT_BITMAP_PLATFORM_DEVICE_MAC_H_
|