chromium/third_party/skia/src/gpu/ganesh/GrBackendTextureImageGenerator.h

/*
 * Copyright 2017 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#ifndef GrBackendTextureImageGenerator_DEFINED
#define GrBackendTextureImageGenerator_DEFINED

#include "include/core/SkRefCnt.h"
#include "include/gpu/ganesh/GrBackendSurface.h"
#include "include/gpu/ganesh/GrDirectContext.h"
#include "include/gpu/ganesh/GrRecordingContext.h"
#include "include/private/base/SkMutex.h"
#include "include/private/gpu/ganesh/GrTextureGenerator.h"
#include "src/gpu/ResourceKey.h"
#include "src/gpu/ganesh/GrSurfaceProxyView.h"

#include <memory>

class GrSemaphore;
class GrTexture;
class SkColorInfo;
class SkColorSpace;
enum GrSurfaceOrigin : int;
enum SkAlphaType : int;
enum SkColorType : int;
enum class GrImageTexGenPolicy : int;
struct SkImageInfo;

namespace skgpu {
class RefCntedCallback;
enum class Mipmapped : bool;
}  // namespace skgpu

/*
 * This ImageGenerator is used to wrap a texture in one GrContext and can then be used as a source
 * in another GrContext. It holds onto a semaphore which the producing GrContext will signal and the
 * consuming GrContext will wait on before using the texture. Only one GrContext can ever be used
 * as a consumer (this is mostly because Vulkan can't allow multiple things to wait on the same
 * semaphore).
 *
 * In practice, this capability is used by clients to create backend-specific texture resources in
 * one thread (with, say, GrContext-A) and then ship them over to another GrContext (say,
 * GrContext-B) which will then use the texture as a source for draws. GrContext-A uses the
 * semaphore to notify GrContext-B when the shared texture is ready to use.
 */
class GrBackendTextureImageGenerator : public GrTextureGenerator { … };
#endif  // GrBackendTextureImageGenerator_DEFINED