ui/gl/gl_image_io_surface.h

// Copyright 2013 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 UI_GL_GL_IMAGE_IO_SURFACE_H_
#define UI_GL_GL_IMAGE_IO_SURFACE_H_

#include <CoreVideo/CVPixelBuffer.h>
#include <IOSurface/IOSurface.h>
#include <stdint.h>

#include "base/mac/scoped_cftyperef.h"
#include "base/macros.h"
#include "base/threading/thread_checker.h"
#include "ui/gfx/buffer_types.h"
#include "ui/gfx/color_space.h"
#include "ui/gfx/generic_shared_memory_id.h"
#include "ui/gl/gl_export.h"
#include "ui/gl/gl_image.h"

#if defined(__OBJC__)
@class CALayer;
#else
typedef void* CALayer;
#endif

namespace gl {

class GL_EXPORT GLImageIOSurface : public GLImage {
 public:
  static GLImageIOSurface* Create(const gfx::Size& size,
                                  unsigned internalformat);

  bool Initialize(IOSurfaceRef io_surface,
                  gfx::GenericSharedMemoryId io_surface_id,
                  gfx::BufferFormat format);

  // IOSurfaces coming from video decode are wrapped in a CVPixelBuffer
  // and may be discarded if the owning CVPixelBuffer is destroyed. This
  // initialization will ensure that the CVPixelBuffer be retained for the
  // lifetime of the GLImage.
  bool InitializeWithCVPixelBuffer(CVPixelBufferRef cv_pixel_buffer,
                                   gfx::GenericSharedMemoryId io_surface_id,
                                   gfx::BufferFormat format);

  // Overridden from GLImage:
  gfx::Size GetSize() override;
  unsigned GetInternalFormat() override;
  bool BindTexImage(unsigned target) override;
  bool BindTexImageWithInternalformat(unsigned target,
                                      unsigned internalformat) override;
  void ReleaseTexImage(unsigned target) override {}
  bool CopyTexImage(unsigned target) override;
  bool CopyTexSubImage(unsigned target,
                       const gfx::Point& offset,
                       const gfx::Rect& rect) override;
  bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                            int z_order,
                            gfx::OverlayTransform transform,
                            const gfx::Rect& bounds_rect,
                            const gfx::RectF& crop_rect) override;
  void SetColorSpace(const gfx::ColorSpace& color_space) override;
  void Flush() override {}
  void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                    uint64_t process_tracing_id,
                    const std::string& dump_name) override;
  bool EmulatingRGB() const override;

  gfx::GenericSharedMemoryId io_surface_id() const { return io_surface_id_; }
  base::ScopedCFTypeRef<IOSurfaceRef> io_surface();
  base::ScopedCFTypeRef<CVPixelBufferRef> cv_pixel_buffer();

  // Whether checking IOSurfaceIsInUse() will actually provide a meaningful
  // signal about whether the Window Server is still using the IOSurface.
  bool CanCheckIOSurfaceIsInUse() const;

  // For IOSurfaces that need manual conversion to a GL texture before being
  // sampled from, specify the color space in which to do the required YUV to
  // RGB transformation.
  void SetColorSpaceForYUVToRGBConversion(const gfx::ColorSpace& color_space);

  static unsigned GetInternalFormatForTesting(gfx::BufferFormat format);

  // Downcasts from |image|. Returns |nullptr| on failure.
  static GLImageIOSurface* FromGLImage(GLImage* image);

 protected:
  ~GLImageIOSurface() override;

 private:
  GLImageIOSurface(const gfx::Size& size, unsigned internalformat);

  Type GetType() const override;
  class RGBConverter;

  const gfx::Size size_;

  // The "internalformat" exposed to the command buffer, which may not be
  // "internalformat" requested by the client.
  const unsigned internalformat_;

  // The "internalformat" requested by the client.
  const unsigned client_internalformat_;

  gfx::BufferFormat format_;
  base::ScopedCFTypeRef<IOSurfaceRef> io_surface_;
  base::ScopedCFTypeRef<CVPixelBufferRef> cv_pixel_buffer_;
  gfx::GenericSharedMemoryId io_surface_id_;

  // Cache the color space, because re-assigning the same value can be
  // expensive.
  gfx::ColorSpace color_space_;

  base::ThreadChecker thread_checker_;
  // The default value of Rec. 601 is based on historical shader code.
  gfx::ColorSpace color_space_for_yuv_to_rgb_ = gfx::ColorSpace::CreateREC601();

  DISALLOW_COPY_AND_ASSIGN(GLImageIOSurface);
};

}  // namespace gl

#endif  // UI_GL_GL_IMAGE_IO_SURFACE_H_