## C Specification

To query the compression properties of an image, add a VkImageCompressionPropertiesEXT structure to the pNext chain of the VkSubresourceLayout2EXT structure in a call to vkGetImageSubresourceLayout2EXT.

To determine the compression rates that are supported for a given image format, add a VkImageCompressionPropertiesEXT structure to the pNext chain of the VkImageFormatProperties2 structure in a call to vkGetPhysicalDeviceImageFormatProperties2.

 Note Since fixed-rate compression is disabled by default, the VkImageCompressionPropertiesEXT structure passed to vkGetPhysicalDeviceImageFormatProperties2 will not indicate any fixed-rate compression support unless a VkImageCompressionControlEXT structure is also included in the pNext chain of the VkPhysicalDeviceImageFormatInfo2 structure passed to the same command.

The VkImageCompressionPropertiesEXT structure is defined as:

// Provided by VK_EXT_image_compression_control
typedef struct VkImageCompressionPropertiesEXT {
VkStructureType                        sType;
void*                                  pNext;
VkImageCompressionFlagsEXT             imageCompressionFlags;
VkImageCompressionFixedRateFlagsEXT    imageCompressionFixedRateFlags;
} VkImageCompressionPropertiesEXT;

## Members

• sType is the type of this structure.

• pNext is NULL or a pointer to a structure extending this structure.

• imageCompressionFlags returns a value describing the compression controls that apply to the image. The value will be either VK_IMAGE_COMPRESSION_DEFAULT_EXT to indicate no fixed-rate compression, VK_IMAGE_COMPRESSION_FIXED_RATE_EXPLICIT_EXT to indicate fixed-rate compression, or VK_IMAGE_COMPRESSION_DISABLED_EXT to indicate no compression.

• imageCompressionFixedRateFlags returns a VkImageCompressionFixedRateFlagsEXT value describing the compression rates that apply to the specified aspect of the image.

## Description

Valid Usage (Implicit)
• VUID-VkImageCompressionPropertiesEXT-sType-sType
sType must be VK_STRUCTURE_TYPE_IMAGE_COMPRESSION_PROPERTIES_EXT