summaryrefslogtreecommitdiffstats
path: root/gfx/gl/GLScreenBuffer.h
blob: ace3145f7ac359cdbd7c469fbbcda9593458d5ac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
/* -*- 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 "GLTypes.h"
#include "mozilla/gfx/Point.h"
#include "mozilla/UniquePtr.h"

#include <functional>
#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:
  size_t mPoolLimit;
  std::queue<std::shared_ptr<SharedSurface>> mPool;
  std::shared_ptr<SharedSurface> mFrontBuffer;
  std::function<void()> mDestroyedCallback;

 public:
  std::shared_ptr<SharedSurface>
      mPrevFrontBuffer;  // Hold this ref while it's in-flight.
 private:
  SwapChainPresenter* mPresenter = nullptr;

 public:
  SwapChain();
  virtual ~SwapChain();

  void DisablePool() {
    if (mPoolLimit) {
      MOZ_ASSERT(mPool.empty());
      mPool = {};
      mPoolLimit = 0;
    }
  }

  void ClearPool();
  bool StoreRecycledSurface(const std::shared_ptr<SharedSurface>& surf);
  const auto& FrontBuffer() const { return mFrontBuffer; }
  UniquePtr<SwapChainPresenter> Acquire(const gfx::IntSize&, gfx::ColorSpace2);

  void SetDestroyedCallback(std::function<void()>&& aDestroyedCallback) {
    MOZ_ASSERT(!mDestroyedCallback);
    mDestroyedCallback = std::move(aDestroyedCallback);
    mPool = {};
  }
};

}  // namespace gl
}  // namespace mozilla

#endif  // SCREEN_BUFFER_H_