Class BufferBlock

framework/buffer_pool.h:149–191

 */
template <vkb::BindingType bindingType>
class BufferBlock
{
  public:
	using BufferUsageFlagsType = typename std::conditional<bindingType == vkb::BindingType::Cpp, vk::BufferUsageFlags, VkBufferUsageFlags>::type;
	using DeviceSizeType       = typename std::conditional<bindingType == vkb::BindingType::Cpp, vk::DeviceSize, VkDeviceSize>::type;

  public:
	BufferBlock()                                  = delete;
	BufferBlock(BufferBlock const &rhs)            = delete;
	BufferBlock(BufferBlock &&rhs)                 = default;
	BufferBlock &operator=(BufferBlock const &rhs) = delete;
	BufferBlock &operator=(BufferBlock &&rhs)      = default;

	BufferBlock(vkb::core::Device<bindingType> &device, DeviceSizeType size, BufferUsageFlagsType usage, VmaMemoryUsage memory_usage);

	/**
	 * @return An usable view on a portion of the underlying buffer
	 */
	BufferAllocation<bindingType> allocate(DeviceSizeType size);

	/**
	 * @brief check if this BufferBlock can allocate a given amount of memory
	 * @param size the number of bytes to check
	 * @return \c true if \a size bytes can be allocated from this \c BufferBlock, otherwise \c false.
	 */
	bool can_allocate(DeviceSizeType size) const;

	DeviceSizeType get_size() const;
	void           reset();

  private:
	/**
	 * @ brief Determine the current aligned offset.
	 * @return The current aligned offset.
	 */
	vk::DeviceSize aligned_offset() const;
	vk::DeviceSize determine_alignment(vk::BufferUsageFlags usage, vk::PhysicalDeviceLimits const &limits) const;

  private:
	vkb::core::BufferCpp buffer;
	vk::DeviceSize       alignment = 0;        // Memory alignment, it may change according to the usage
	vk::DeviceSize       offset    = 0;        // Current offset, it increases on every allocation
};

using BufferBlockC   = BufferBlock<vkb::BindingType::C>;
using BufferBlockCpp = BufferBlock<vkb::BindingType::Cpp>;