Documentation

Creates Allocator object.

A convenience wrapper to make a compatible pair of calls to createAllocator and destroyAllocator

To ensure that destroyAllocator is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Destroys allocator object.

Returns information about existing Allocator object - handle to Vulkan device etc.

It might be useful if you want to keep just the Allocator handle and fetch other required handles to VkPhysicalDevice, VkDevice etc. every time using this function.

PhysicalDeviceProperties are fetched from physicalDevice by the allocator. You can access it here, without fetching it again on your own.

PhysicalDeviceMemoryProperties are fetched from physicalDevice by the allocator. You can access it here, without fetching it again on your own.

Given Memory Type Index, returns Property Flags of this memory type.

This is just a convenience function. Same information can be obtained using getMemoryProperties.

Sets index of the current frame.

This function must be used if you make allocations with ALLOCATION_CREATE_CAN_BECOME_LOST_BIT and ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT flags to inform the allocator when a new frame begins. Allocations queried using getAllocationInfo cannot become lost in the current frame.

Retrieves statistics from current state of the Allocator.

This function is called "calculate" not "get" because it has to traverse all internal data structures, so it may be quite slow. For faster but more brief statistics suitable to be called every frame or every allocation, use getBudget.

Note that when using allocator from multiple threads, returned information may immediately become outdated.

Retrieves information about current memory budget for all memory heaps.

Parameters.

This function is called "get" not "calculate" because it is very fast, suitable to be called every frame or every allocation. For more detailed statistics use calculateStats.

Note that when using allocator from multiple threads, returned information may immediately become outdated.

Builds and returns statistics as string in JSON format.

Parameters.

Helps to find memoryTypeIndex, given memoryTypeBits and AllocationCreateInfo.

This algorithm tries to find a memory type that:

• Is allowed by memoryTypeBits.
• Contains all the flags from pAllocationCreateInfo->requiredFlags.
• Matches intended usage.
• Has as many flags from pAllocationCreateInfo->preferredFlags as possible.

Returns.

Returns VK_ERROR_FEATURE_NOT_PRESENT if not found. Receiving such result from this function or any other allocating function probably means that your device doesn't support any memory type with requested features for the specific type of resource you want to use it for. Please check parameters of your resource, like image layout (OPTIMAL versus LINEAR) or mip level count.

Helps to find memoryTypeIndex, given VkBufferCreateInfo and AllocationCreateInfo.

It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex. It internally creates a temporary, dummy buffer that never has memory bound. It is just a convenience function, equivalent to calling:

• vkCreateBuffer

• vkGetBufferMemoryRequirements

• findMemoryTypeIndex

• vkDestroyBuffer

Helps to find memoryTypeIndex, given VkImageCreateInfo and AllocationCreateInfo.

It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex. It internally creates a temporary, dummy image that never has memory bound. It is just a convenience function, equivalent to calling:

• vkCreateImage

• vkGetImageMemoryRequirements

• findMemoryTypeIndex

• vkDestroyImage

Allocates Vulkan device memory and creates Pool object.

Parameters.

A convenience wrapper to make a compatible pair of calls to createPool and destroyPool

To ensure that destroyPool is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Destroys Pool object and frees Vulkan device memory.

Retrieves statistics of existing Pool object.

Parameters.

Marks all allocations in given pool as lost if they are not used in current frame or VmaPoolCreateInfo::frameInUseCount back from now.

Parameters.

Checks magic number in margins around all allocations in given memory pool in search for corruptions.

Corruption detection is enabled only when VMA_DEBUG_DETECT_CORRUPTION macro is defined to nonzero, VMA_DEBUG_MARGIN is defined to nonzero and the pool is created in memory type that is HOST_VISIBLE and HOST_COHERENT. For more information, see Corruption detection.

Possible return values:

• VK_ERROR_FEATURE_NOT_PRESENT - corruption detection is not enabled for specified pool.
• VK_SUCCESS - corruption detection has been performed and succeeded.
• VK_ERROR_VALIDATION_FAILED_EXT - corruption detection has been performed and found memory corruptions around one of the allocations. VMA_ASSERT is also fired in that case.
• Other value: Error returned by Vulkan, e.g. memory mapping failure.

Retrieves name of a custom pool.

After the call ppName is either null or points to an internally-owned null-terminated string containing name of the pool that was previously set. The pointer becomes invalid when the pool is destroyed or its name is changed using setPoolName.

Sets name of a custom pool.

pName can be either null or pointer to a null-terminated string with new name for the pool. Function makes internal copy of the string, so it can be changed or freed immediately after this call.

General purpose memory allocation.

Parameters.

You should free the memory using freeMemory or freeMemoryPages.

It is recommended to use allocateMemoryForBuffer, allocateMemoryForImage, createBuffer, createImage instead whenever possible.

A convenience wrapper to make a compatible pair of calls to allocateMemory and freeMemory

To ensure that freeMemory is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

General purpose memory allocation for multiple allocation objects at once.

Parameters.

You should free the memory using freeMemory or freeMemoryPages.

Word "pages" is just a suggestion to use this function to allocate pieces of memory needed for sparse binding. It is just a general purpose allocation function able to make multiple allocations at once. It may be internally optimized to be more efficient than calling allocateMemory allocationCount times.

All allocations are made using same parameters. All of them are created out of the same memory pool and type. If any allocation fails, all allocations already made within this function call are also freed, so that when returned result is not VK_SUCCESS, pAllocation array is always entirely filled with VK_NULL_HANDLE.

A convenience wrapper to make a compatible pair of calls to allocateMemoryPages and freeMemoryPages

To ensure that freeMemoryPages is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Parameters.

You should free the memory using freeMemory.

A convenience wrapper to make a compatible pair of calls to allocateMemoryForBuffer and freeMemory

To ensure that freeMemory is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Function similar to allocateMemoryForBuffer.

A convenience wrapper to make a compatible pair of calls to allocateMemoryForImage and freeMemory

To ensure that freeMemory is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Frees memory previously allocated using allocateMemory, allocateMemoryForBuffer, or allocateMemoryForImage.

Passing VK_NULL_HANDLE as allocation is valid. Such function call is just skipped.

Frees memory and destroys multiple allocations.

Word "pages" is just a suggestion to use this function to free pieces of memory used for sparse binding. It is just a general purpose function to free memory and destroy allocations made using e.g. allocateMemory, allocateMemoryPages and other functions. It may be internally optimized to be more efficient than calling freeMemory allocationCount times.

Allocations in pAllocations array can come from any memory pools and types. Passing VK_NULL_HANDLE as elements of pAllocations array is valid. Such entries are just skipped.

Deprecated.

Deprecated

In version 2.2.0 it used to try to change allocation's size without moving or reallocating it. In current version it returns VK_SUCCESS only if newSize equals current allocation's size. Otherwise returns VK_ERROR_OUT_OF_POOL_MEMORY, indicating that allocation's size could not be changed.

Returns current information about specified allocation and atomically marks it as used in current frame.

Current paramters of given allocation are returned in pAllocationInfo.

This function also atomically "touches" allocation - marks it as used in current frame, just like touchAllocation. If the allocation is in lost state, pAllocationInfo->deviceMemory == VK_NULL_HANDLE.

Although this function uses atomics and doesn't lock any mutex, so it should be quite efficient, you can avoid calling it too often.

• You can retrieve same AllocationInfo structure while creating your resource, from function createBuffer, createImage. You can remember it if you are sure parameters don't change (e.g. due to defragmentation or allocation becoming lost).
• If you just want to check if allocation is not lost, touchAllocation will work faster.

Returns VK_TRUE if allocation is not lost and atomically marks it as used in current frame.

If the allocation has been created with ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag, this function returns VK_TRUE if it's not in lost state, so it can still be used. It then also atomically "touches" the allocation - marks it as used in current frame, so that you can be sure it won't become lost in current frame or next frameInUseCount frames.

If the allocation is in lost state, the function returns VK_FALSE. Memory of such allocation, as well as buffer or image bound to it, should not be used. Lost allocation and the buffer/image still need to be destroyed.

If the allocation has been created without ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag, this function always returns VK_TRUE.

Sets pUserData in given allocation to new value.

If the allocation was created with VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT, pUserData must be either null, or pointer to a null-terminated string. The function makes local copy of the string and sets it as allocation's pUserData. String passed as pUserData doesn't need to be valid for whole lifetime of the allocation - you can free it after this call. String previously pointed by allocation's pUserData is freed from memory.

If the flag was not used, the value of pointer pUserData is just copied to allocation's pUserData. It is opaque, so you can use it however you want - e.g. as a pointer, ordinal number or some handle to you own data.

Creates new allocation that is in lost state from the beginning.

It can be useful if you need a dummy, non-null allocation.

You still need to destroy created object using freeMemory.

Returned allocation is not tied to any specific memory pool or memory type and not bound to any image or buffer. It has size = 0. It cannot be turned into a real, non-empty allocation.

A convenience wrapper to make a compatible pair of calls to createLostAllocation and freeMemory

To ensure that freeMemory is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Maps memory represented by given allocation and returns pointer to it.

Maps memory represented by given allocation to make it accessible to CPU code. When succeeded, *ppData contains pointer to first byte of this memory. If the allocation is part of bigger VkDeviceMemory block, the pointer is correctly offseted to the beginning of region assigned to this particular allocation.

Mapping is internally reference-counted and synchronized, so despite raw Vulkan function vkMapMemory() cannot be used to map same block of VkDeviceMemory multiple times simultaneously, it is safe to call this function on allocations assigned to the same memory block. Actual Vulkan memory will be mapped on first mapping and unmapped on last unmapping.

If the function succeeded, you must call unmapMemory to unmap the allocation when mapping is no longer needed or before freeing the allocation, at the latest.

It also safe to call this function multiple times on the same allocation. You must call unmapMemory same number of times as you called mapMemory.

It is also safe to call this function on allocation created with ALLOCATION_CREATE_MAPPED_BIT flag. Its memory stays mapped all the time. You must still call unmapMemory same number of times as you called mapMemory. You must not call unmapMemory additional time to free the "0-th" mapping made automatically due to ALLOCATION_CREATE_MAPPED_BIT flag.

This function fails when used on allocation made in memory type that is not HOST_VISIBLE.

This function always fails when called for allocation that was created with ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag. Such allocations cannot be mapped.

This function doesn't automatically flush or invalidate caches. If the allocation is made from a memory types that is not HOST_COHERENT, you also need to use invalidateAllocation / flushAllocation, as required by Vulkan specification.

A convenience wrapper to make a compatible pair of calls to mapMemory and unmapMemory

To ensure that unmapMemory is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Unmaps memory represented by given allocation, mapped previously using mapMemory.

For details, see description of mapMemory.

This function doesn't automatically flush or invalidate caches. If the allocation is made from a memory types that is not HOST_COHERENT, you also need to use invalidateAllocation / flushAllocation, as required by Vulkan specification.

Flushes memory of given allocation.

Calls vkFlushMappedMemoryRanges() for memory associated with given range of given allocation. It needs to be called after writing to a mapped memory for memory types that are not HOST_COHERENT. Unmap operation doesn't do that automatically.

• offset must be relative to the beginning of allocation.
• size can be VK_WHOLE_SIZE. It means all memory from offset the the end of given allocation.
• offset and size don't have to be aligned. They are internally rounded down/up to multiply of nonCoherentAtomSize.
• If size is 0, this call is ignored.
• If memory type that the allocation belongs to is not HOST_VISIBLE or it is HOST_COHERENT, this call is ignored.

Warning! offset and size are relative to the contents of given allocation. If you mean whole allocation, you can pass 0 and VK_WHOLE_SIZE, respectively. Do not pass allocation's offset as offset!!!

This function returns the VkResult from vkFlushMappedMemoryRanges if it is called, otherwise VK_SUCCESS.

Invalidates memory of given allocation.

Calls vkInvalidateMappedMemoryRanges() for memory associated with given range of given allocation. It needs to be called before reading from a mapped memory for memory types that are not HOST_COHERENT. Map operation doesn't do that automatically.

• offset must be relative to the beginning of allocation.
• size can be VK_WHOLE_SIZE. It means all memory from offset the the end of given allocation.
• offset and size don't have to be aligned. They are internally rounded down/up to multiply of nonCoherentAtomSize.
• If size is 0, this call is ignored.
• If memory type that the allocation belongs to is not HOST_VISIBLE or it is HOST_COHERENT, this call is ignored.

Warning! offset and size are relative to the contents of given allocation. If you mean whole allocation, you can pass 0 and VK_WHOLE_SIZE, respectively. Do not pass allocation's offset as offset!!!

This function returns the VkResult from vkInvalidateMappedMemoryRanges if it is called, otherwise VK_SUCCESS.

Flushes memory of given set of allocations.

Calls vkFlushMappedMemoryRanges() for memory associated with given ranges of given allocations. For more information, see documentation of flushAllocation.

Parameters.

This function returns the VkResult from vkFlushMappedMemoryRanges if it is called, otherwise VK_SUCCESS.

Invalidates memory of given set of allocations.

Calls vkInvalidateMappedMemoryRanges() for memory associated with given ranges of given allocations. For more information, see documentation of invalidateAllocation.

Parameters.

This function returns the VkResult from vkInvalidateMappedMemoryRanges if it is called, otherwise VK_SUCCESS.

Checks magic number in margins around all allocations in given memory types (in both default and custom pools) in search for corruptions.

Parameters.

Corruption detection is enabled only when VMA_DEBUG_DETECT_CORRUPTION macro is defined to nonzero, VMA_DEBUG_MARGIN is defined to nonzero and only for memory types that are HOST_VISIBLE and HOST_COHERENT. For more information, see Corruption detection.

Possible return values:

• VK_ERROR_FEATURE_NOT_PRESENT - corruption detection is not enabled for any of specified memory types.
• VK_SUCCESS - corruption detection has been performed and succeeded.
• VK_ERROR_VALIDATION_FAILED_EXT - corruption detection has been performed and found memory corruptions around one of the allocations. VMA_ASSERT is also fired in that case.
• Other value: Error returned by Vulkan, e.g. memory mapping failure.

Begins defragmentation process.

Parameters.

Returns.

VK_SUCCESS and *pContext == null if defragmentation finished within this function call. VK_NOT_READY and *pContext != null if defragmentation has been started and you need to call defragmentationEnd to finish it. Negative value in case of error.

Use this function instead of old, deprecated defragment.

Warning! Between the call to defragmentationBegin and defragmentationEnd:

• You should not use any of allocations passed as pInfo->pAllocations or any allocations that belong to pools passed as pInfo->pPools, including calling getAllocationInfo, touchAllocation, or access their data.
• Some mutexes protecting internal data structures may be locked, so trying to make or free any allocations, bind buffers or images, map memory, or launch another simultaneous defragmentation in between may cause stall (when done on another thread) or deadlock (when done on the same thread), unless you are 100% sure that defragmented allocations are in different pools.
• Information returned via pStats and pInfo->pAllocationsChanged are undefined. They become valid after call to defragmentationEnd.
• If pInfo->commandBuffer is not null, you must submit that command buffer and make sure it finished execution before calling defragmentationEnd.

For more information and important limitations regarding defragmentation, see documentation chapter: Defragmentation.

A convenience wrapper to make a compatible pair of calls to defragmentationBegin and defragmentationEnd

To ensure that defragmentationEnd is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Ends defragmentation process.

Use this function to finish defragmentation started by defragmentationBegin. It is safe to pass context == null. The function then does nothing.

This function will call the supplied action between calls to beginDefragmentationPass and endDefragmentationPass

Note that endDefragmentationPass is *not* called if an exception is thrown by the inner action.

Deprecated. Compacts memory by moving allocations.

Parameters.

Returns.

VK_SUCCESS if completed, negative error code in case of error.

Deprecated

This is a part of the old interface. It is recommended to use structure DefragmentationInfo2 and function defragmentationBegin instead.

This function works by moving allocations to different places (different VkDeviceMemory objects and/or different offsets) in order to optimize memory usage. Only allocations that are in pAllocations array can be moved. All other allocations are considered nonmovable in this call. Basic rules:

• Only allocations made in memory types that have VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT and VK_MEMORY_PROPERTY_HOST_COHERENT_BIT flags can be compacted. You may pass other allocations but it makes no sense - these will never be moved.
• Custom pools created with POOL_CREATE_LINEAR_ALGORITHM_BIT or POOL_CREATE_BUDDY_ALGORITHM_BIT flag are not defragmented. Allocations passed to this function that come from such pools are ignored.
• Allocations created with ALLOCATION_CREATE_DEDICATED_MEMORY_BIT or created as dedicated allocations for any other reason are also ignored.
• Both allocations made with or without ALLOCATION_CREATE_MAPPED_BIT flag can be compacted. If not persistently mapped, memory will be mapped temporarily inside this function if needed.
• You must not pass same Allocation object multiple times in pAllocations array.

The function also frees empty VkDeviceMemory blocks.

Warning: This function may be time-consuming, so you shouldn't call it too often (like after every resource creation/destruction). You can call it on special occasions (like when reloading a game level or when you just destroyed a lot of objects). Calling it every frame may be OK, but you should measure that on your platform.

For more information, see Defragmentation chapter.

Binds buffer to allocation.

Binds specified buffer to region of memory represented by specified allocation. Gets VkDeviceMemory handle and offset from the allocation. If you want to create a buffer, allocate memory for it and bind them together separately, you should use this function for binding instead of standard vkBindBufferMemory(), because it ensures proper synchronization so that when a VkDeviceMemory object is used by multiple allocations, calls to vkBind*Memory() or vkMapMemory() won't happen from multiple threads simultaneously (which is illegal in Vulkan).

It is recommended to use function createBuffer instead of this one.

Binds buffer to allocation with additional parameters.

Parameters.

This function is similar to bindBufferMemory, but it provides additional parameters.

If pNext is not null, Allocator object must have been created with ALLOCATOR_CREATE_KHR_BIND_MEMORY2_BIT flag or with VmaAllocatorCreateInfo::vulkanApiVersion == VK_API_VERSION_1_1. Otherwise the call fails.

Binds image to allocation.

Binds specified image to region of memory represented by specified allocation. Gets VkDeviceMemory handle and offset from the allocation. If you want to create an image, allocate memory for it and bind them together separately, you should use this function for binding instead of standard vkBindImageMemory(), because it ensures proper synchronization so that when a VkDeviceMemory object is used by multiple allocations, calls to vkBind*Memory() or vkMapMemory() won't happen from multiple threads simultaneously (which is illegal in Vulkan).

It is recommended to use function createImage instead of this one.

Binds image to allocation with additional parameters.

Parameters.

This function is similar to bindImageMemory, but it provides additional parameters.

If pNext is not null, Allocator object must have been created with ALLOCATOR_CREATE_KHR_BIND_MEMORY2_BIT flag or with VmaAllocatorCreateInfo::vulkanApiVersion == VK_API_VERSION_1_1. Otherwise the call fails.

Parameters.

This function automatically:

1. Creates buffer.
2. Allocates appropriate memory for it.
3. Binds the buffer with the memory.

If any of these operations fail, buffer and allocation are not created, returned value is negative error code, *pBuffer and *pAllocation are null.

If the function succeeded, you must destroy both buffer and allocation when you no longer need them using either convenience function destroyBuffer or separately, using vkDestroyBuffer() and freeMemory.

If VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT flag was used, VK_KHR_dedicated_allocation extension is used internally to query driver whether it requires or prefers the new buffer to have dedicated allocation. If yes, and if dedicated allocation is possible (VmaAllocationCreateInfo::pool is null and VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT is not used), it creates dedicated allocation for this buffer, just like when using VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.

A convenience wrapper to make a compatible pair of calls to createBuffer and destroyBuffer

To ensure that destroyBuffer is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Destroys Vulkan buffer and frees allocated memory.

This is just a convenience function equivalent to:

vkDestroyBuffer(device, buffer, allocationCallbacks);
 vmaFreeMemory(allocator, allocation);

It it safe to pass null as buffer and/or allocation.

Function similar to createBuffer.

A convenience wrapper to make a compatible pair of calls to createImage and destroyImage

To ensure that destroyImage is always called: pass bracket (or the allocate function from your favourite resource management library) as the first argument. To just extract the pair pass (,) as the first argument.

Destroys Vulkan image and frees allocated memory.

This is just a convenience function equivalent to:

vkDestroyImage(device, image, allocationCallbacks);
 vmaFreeMemory(allocator, allocation);

It it safe to pass null as image and/or allocation.

VmaAllocator

Represents main object of this library initialized.

Fill structure AllocatorCreateInfo and call function createAllocator to create it. Call function destroyAllocator to destroy it.

It is recommended to create just one object of this type per VkDevice object, right after Vulkan is initialized and keep it alive until before Vulkan device is destroyed.

VmaDeviceMemoryCallbacks

Set of callbacks that the library will call for vkAllocateMemory and vkFreeMemory.

Provided for informative purpose, e.g. to gather statistics about number of allocations or total amount of memory allocated in Vulkan.

Used in VmaAllocatorCreateInfo::pDeviceMemoryCallbacks.

Flags for created Allocator.

VmaVulkanFunctions

Pointers to some Vulkan functions - a subset used by the library.

Used in VmaAllocatorCreateInfo::pVulkanFunctions.

Flags to be used in VmaRecordSettings::flags.

VmaRecordSettings

Parameters for recording calls to VMA functions. To be used in VmaAllocatorCreateInfo::pRecordSettings.

VmaAllocatorCreateInfo

Description of a Allocator to be created.

VmaAllocatorInfo

Information about existing Allocator object.

VmaStatInfo

Calculated statistics of memory usage in entire allocator.

VmaStats

• StatInfo memoryType [VK_MAX_MEMORY_TYPES]
• StatInfo memoryHeap [VK_MAX_MEMORY_HEAPS]
• StatInfo total

General statistics from current state of Allocator.

memoryHeap

memoryHeap VmaStats VmaStats memoryHeap VmaStatInfo VmaStats::memoryHeap[VK_MAX_MEMORY_HEAPS]

memoryType

memoryType VmaStats VmaStats memoryType VmaStatInfo VmaStats::memoryType[VK_MAX_MEMORY_TYPES]

VmaBudget

Statistics of current memory usage and available budget, in bytes, for specific memory heap.

VmaPool

Represents custom memory pool.

Fill structure PoolCreateInfo and call function createPool to create it. Call function destroyPool to destroy it.

For more information see Custom memory pools.

Flags to be passed as VmaAllocationCreateInfo::flags.