Setting an image memory barrier

Images are created for various purposes--they are used as textures, by binding them to a pipeline via descriptor sets, as render targets, or as presentable images in swapchains. We can copy data to or from images--these are also separate usages defined during image creation.

Before we start using an image for any purpose, and every time we want to change the current usage of a given image, we need to inform a driver about this operation. We do this by using image memory barriers which are set during command buffer recording.

Getting ready

For the purpose of this recipe, a custom structure type ImageTransition is introduced. It has the following definition:

struct ImageTransition { 
  VkImage             Image; 
  VkAccessFlags       CurrentAccess; 
  VkAccessFlags       NewAccess; 
  VkImageLayout       CurrentLayout; 
  VkImageLayout       NewLayout; 
  uint32_t            CurrentQueueFamily; 
  uint32_t            NewQueueFamily; 
  VkImageAspectFlags  Aspect...