910e62b5创建于 1月15日历史提交
// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef GPU_COMMAND_BUFFER_COMMON_GPU_MEMORY_ALLOCATION_H_
#define GPU_COMMAND_BUFFER_COMMON_GPU_MEMORY_ALLOCATION_H_

#include <stdint.h>

namespace gpu {

// These are per context memory allocation limits set by the GpuMemoryManager
// and assigned to the browser and renderer context.
// They will change over time, given memory availability, and browser state.
struct MemoryAllocation {
  enum PriorityCutoff {
    // Allow no allocations.
    CUTOFF_ALLOW_NOTHING,
    // Allow only allocations that are strictly required for correct rendering.
    // For compositors, this is what is visible.
    CUTOFF_ALLOW_REQUIRED_ONLY,
    // Allow allocations that are not strictly needed for correct rendering, but
    // are nice to have for performance. For compositors, this includes textures
    // that are a few screens away from being visible.
    CUTOFF_ALLOW_NICE_TO_HAVE,
    // Allow all allocations.
    CUTOFF_ALLOW_EVERYTHING,
    CUTOFF_LAST = CUTOFF_ALLOW_EVERYTHING
  };

  // Limits when this renderer is visible.
  uint64_t bytes_limit_when_visible;
  PriorityCutoff priority_cutoff_when_visible;

  MemoryAllocation()
      : bytes_limit_when_visible(0),
        priority_cutoff_when_visible(CUTOFF_ALLOW_NOTHING) {
  }

  MemoryAllocation(uint64_t bytes_limit_when_visible)
      : bytes_limit_when_visible(bytes_limit_when_visible),
        priority_cutoff_when_visible(CUTOFF_ALLOW_EVERYTHING) {}

  bool Equals(const MemoryAllocation& other) const {
    return bytes_limit_when_visible ==
               other.bytes_limit_when_visible &&
        priority_cutoff_when_visible == other.priority_cutoff_when_visible;
  }
};

}  // namespace content

#endif // GPU_COMMAND_BUFFER_COMMON_GPU_MEMORY_ALLOCATION_H_