gecko-dev/gfx/gl/GLScreenBuffer.h
2020-07-04 09:38:43 +00:00

82 lines
2.1 KiB
C++

/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 4; -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* GLScreenBuffer is the abstraction for the "default framebuffer" used
* by an offscreen GLContext. Since it's only for offscreen GLContext's,
* it's only useful for things like WebGL, and is NOT used by the
* compositor's GLContext. Remember that GLContext provides an abstraction
* so that even if you want to draw to the 'screen', even if that's not
* actually the screen, just draw to 0. This GLScreenBuffer class takes the
* logic handling out of GLContext.
*/
#ifndef SCREEN_BUFFER_H_
#define SCREEN_BUFFER_H_
#include "GLContextTypes.h"
#include "GLDefs.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/Point.h"
#include "mozilla/UniquePtr.h"
#include "SurfaceTypes.h"
#include <queue>
#include <memory>
namespace mozilla {
namespace gl {
class SharedSurface;
class SurfaceFactory;
class SwapChain;
class SwapChainPresenter final {
friend class SwapChain;
SwapChain* mSwapChain;
std::shared_ptr<SharedSurface> mBackBuffer;
public:
explicit SwapChainPresenter(SwapChain& swapChain);
~SwapChainPresenter();
const auto& BackBuffer() const { return mBackBuffer; }
std::shared_ptr<SharedSurface> SwapBackBuffer(std::shared_ptr<SharedSurface>);
GLuint Fb() const;
};
// -
class SwapChain final {
friend class SwapChainPresenter;
public:
UniquePtr<SurfaceFactory> mFactory;
private:
std::queue<std::shared_ptr<SharedSurface>> mPool;
std::shared_ptr<SharedSurface> mFrontBuffer;
public:
std::shared_ptr<SharedSurface>
mPrevFrontBuffer; // Hold this ref while it's in-flight.
private:
SwapChainPresenter* mPresenter = nullptr;
public:
SwapChain();
virtual ~SwapChain();
void ClearPool();
const auto& FrontBuffer() const { return mFrontBuffer; }
UniquePtr<SwapChainPresenter> Acquire(const gfx::IntSize&);
};
} // namespace gl
} // namespace mozilla
#endif // SCREEN_BUFFER_H_