org.lwjgl.vulkan

Class KHRDrawIndirectCount

java.lang.Object

org.lwjgl.vulkan.KHRDrawIndirectCount

public class KHRDrawIndirectCount
extends java.lang.Object

This extension is based off the VK_AMD_draw_indirect_count extension. This extension allows an application to source the number of draw calls for indirect draw calls from a buffer. This enables applications to generate arbitrary amounts of draw commands and execute them without host intervention.

Name String

VK_KHR_draw_indirect_count

Extension Type

Device extension

Registered Extension Number

170

Revision

1

Extension and Version Dependencies

• Requires Vulkan 1.0

Contact

• Piers Daniell pdaniell-nv

Status

Draft

Last Modified Date

2017-08-25

IP Status

No known IP claims.

Contributors

• Matthaeus G. Chajdas, AMD
• Derrick Owens, AMD
• Graham Sellers, AMD
• Daniel Rakos, AMD
• Dominik Witczak, AMD
• Piers Daniell, NVIDIA

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	VK_KHR_DRAW_INDIRECT_COUNT_EXTENSION_NAME The extension name.
static int	VK_KHR_DRAW_INDIRECT_COUNT_SPEC_VERSION The extension specification version.

Method Summary

Modifier and Type	Method and Description
static void	vkCmdDrawIndexedIndirectCountKHR(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, long buffer, long offset, long countBuffer, long countBufferOffset, int maxDrawCount, int stride) Perform an indexed indirect draw with the draw count sourced from a buffer.
static void	vkCmdDrawIndirectCountKHR(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, long buffer, long offset, long countBuffer, long countBufferOffset, int maxDrawCount, int stride) Perform an indirect draw with the draw count sourced from a buffer.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VK_KHR_DRAW_INDIRECT_COUNT_SPEC_VERSION

public static final int VK_KHR_DRAW_INDIRECT_COUNT_SPEC_VERSION

The extension specification version.

See Also:

Constant Field Values

VK_KHR_DRAW_INDIRECT_COUNT_EXTENSION_NAME

public static final java.lang.String VK_KHR_DRAW_INDIRECT_COUNT_EXTENSION_NAME

The extension name.

See Also:

Constant Field Values

Method Detail

vkCmdDrawIndirectCountKHR

public static void vkCmdDrawIndirectCountKHR(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                             long buffer,
                                             long offset,
                                             long countBuffer,
                                             long countBufferOffset,
                                             int maxDrawCount,
                                             int stride)

Perform an indirect draw with the draw count sourced from a buffer.

C Specification

To record a non-indexed draw call with a draw call count sourced from a buffer, call:

 void vkCmdDrawIndirectCountKHR(
     VkCommandBuffer                             commandBuffer,
     VkBuffer                                    buffer,
     VkDeviceSize                                offset,
     VkBuffer                                    countBuffer,
     VkDeviceSize                                countBufferOffset,
     uint32_t                                    maxDrawCount,
     uint32_t                                    stride);

or the equivalent command

 void vkCmdDrawIndirectCountAMD(
     VkCommandBuffer                             commandBuffer,
     VkBuffer                                    buffer,
     VkDeviceSize                                offset,
     VkBuffer                                    countBuffer,
     VkDeviceSize                                countBufferOffset,
     uint32_t                                    maxDrawCount,
     uint32_t                                    stride);

Description

vkCmdDrawIndirectCountKHR behaves similarly to CmdDrawIndirect except that the draw count is read by the device from a buffer during execution. The command will read an unsigned 32-bit integer from countBuffer located at countBufferOffset and use this as the draw count.

Valid Usage

• If a VkImageView is sampled with FILTER_LINEAR as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT
• If a VkImageView is accessed using atomic operations as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_STORAGE_IMAGE_ATOMIC_BIT
• If a VkImageView is sampled with FILTER_CUBIC_EXT as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_CUBIC_BIT_EXT
• Any VkImageView being sampled with FILTER_CUBIC_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubic returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImageView being sampled with FILTER_CUBIC_EXT with a reduction mode of either SAMPLER_REDUCTION_MODE_MIN_EXT or SAMPLER_REDUCTION_MODE_MAX_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering together with minmax filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubicMinmax returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImage created with a VkImageCreateInfo::flags containing IMAGE_CREATE_CORNER_SAMPLED_BIT_NV sampled as a result of this command must only be sampled using a VkSamplerAddressMode of SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE.
• For each set n that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a descriptor set must have been bound to n at the same pipeline bind point, with a VkPipelineLayout that is compatible for set n, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• For each push constant that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a push constant value must have been set for the same pipeline bind point, with a VkPipelineLayout that is compatible for push constants, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• Descriptors in each bound descriptor set, specified via vkCmdBindDescriptorSets, must be valid if they are statically used by the VkPipeline bound to the pipeline bind point used by this command
• A valid pipeline must be bound to the pipeline bind point used by this command
• If the VkPipeline object bound to the pipeline bind point used by this command requires any dynamic state, that state must have been set for commandBuffer
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used to sample from any VkImage with a VkImageView of the type IMAGE_VIEW_TYPE_3D, IMAGE_VIEW_TYPE_CUBE, IMAGE_VIEW_TYPE_1D_ARRAY, IMAGE_VIEW_TYPE_2D_ARRAY or IMAGE_VIEW_TYPE_CUBE_ARRAY, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions with ImplicitLod, Dref or Proj in their name, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions that includes a LOD bias or any offset values, in any shader stage
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a uniform buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a storage buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If commandBuffer is an unprotected command buffer, any resource accessed by the VkPipeline object bound to the pipeline bind point used by this command must not be a protected resource
• The current render pass must be compatible with the renderPass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• The subpass index of the current render pass must be equal to the subpass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• Every input attachment used by the current subpass must be bound to the pipeline via a descriptor set
• Image subresources used as attachments in the current render pass must not be accessed in any way other than as an attachment by this command.
• If the draw is recorded in a render pass instance with multiview enabled, the maximum instance index must be less than or equal to VkPhysicalDeviceMultiviewProperties::maxMultiviewInstanceIndex.
• If the bound graphics pipeline was created with VkPipelineSampleLocationsStateCreateInfoEXT::sampleLocationsEnable set to TRUE and the current subpass has a depth/stencil attachment, then that attachment must have been created with the IMAGE_CREATE_SAMPLE_LOCATIONS_COMPATIBLE_DEPTH_BIT_EXT bit set
• All vertex input bindings accessed via vertex input variables declared in the vertex shader entry point’s interface must have valid buffers bound
• For a given vertex buffer binding, any attribute data fetched must be entirely contained within the corresponding vertex buffer binding, as described in Vertex Input Description
• If buffer is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object
• buffer must have been created with the BUFFER_USAGE_INDIRECT_BUFFER_BIT bit set
• offset must be a multiple of 4
• commandBuffer must not be a protected command buffer
• If countBuffer is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object
• countBuffer must have been created with the BUFFER_USAGE_INDIRECT_BUFFER_BIT bit set
• countBufferOffset must be a multiple of 4
• The count stored in countBuffer must be less than or equal to VkPhysicalDeviceLimits::maxDrawIndirectCount
• stride must be a multiple of 4 and must be greater than or equal to sizeof(VkDrawIndirectCommand)
• If maxDrawCount is greater than or equal to 1, (stride × (maxDrawCount - 1) + offset + sizeof(VkDrawIndirectCommand)) must be less than or equal to the size of buffer
• If the count stored in countBuffer is equal to 1, (offset + sizeof(VkDrawIndirectCommand)) must be less than or equal to the size of buffer
• If the count stored in countBuffer is greater than 1, (stride × (drawCount - 1) + offset + sizeof(VkDrawIndirectCommand)) must be less than or equal to the size of buffer

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• buffer must be a valid VkBuffer handle
• countBuffer must be a valid VkBuffer handle
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• This command must only be called inside of a render pass instance
• Each of buffer, commandBuffer, and countBuffer must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Inside	Graphics	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

buffer - the buffer containing draw parameters.

offset - the byte offset into buffer where parameters begin.

countBuffer - the buffer containing the draw count.

countBufferOffset - the byte offset into countBuffer where the draw count begins.

maxDrawCount - specifies the maximum number of draws that will be executed. The actual number of executed draw calls is the minimum of the count specified in countBuffer and maxDrawCount.

stride - the byte stride between successive sets of draw parameters.

vkCmdDrawIndexedIndirectCountKHR

public static void vkCmdDrawIndexedIndirectCountKHR(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                    long buffer,
                                                    long offset,
                                                    long countBuffer,
                                                    long countBufferOffset,
                                                    int maxDrawCount,
                                                    int stride)

Perform an indexed indirect draw with the draw count sourced from a buffer.

C Specification

To record an indexed draw call with a draw call count sourced from a buffer, call:

 void vkCmdDrawIndexedIndirectCountKHR(
     VkCommandBuffer                             commandBuffer,
     VkBuffer                                    buffer,
     VkDeviceSize                                offset,
     VkBuffer                                    countBuffer,
     VkDeviceSize                                countBufferOffset,
     uint32_t                                    maxDrawCount,
     uint32_t                                    stride);

or the equivalent command

 void vkCmdDrawIndexedIndirectCountAMD(
     VkCommandBuffer                             commandBuffer,
     VkBuffer                                    buffer,
     VkDeviceSize                                offset,
     VkBuffer                                    countBuffer,
     VkDeviceSize                                countBufferOffset,
     uint32_t                                    maxDrawCount,
     uint32_t                                    stride);

Description

vkCmdDrawIndexedIndirectCountKHR behaves similarly to CmdDrawIndexedIndirect except that the draw count is read by the device from a buffer during execution. The command will read an unsigned 32-bit integer from countBuffer located at countBufferOffset and use this as the draw count.

Valid Usage

• If a VkImageView is sampled with FILTER_LINEAR as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT
• If a VkImageView is accessed using atomic operations as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_STORAGE_IMAGE_ATOMIC_BIT
• If a VkImageView is sampled with FILTER_CUBIC_EXT as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_CUBIC_BIT_EXT
• Any VkImageView being sampled with FILTER_CUBIC_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubic returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImageView being sampled with FILTER_CUBIC_EXT with a reduction mode of either SAMPLER_REDUCTION_MODE_MIN_EXT or SAMPLER_REDUCTION_MODE_MAX_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering together with minmax filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubicMinmax returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImage created with a VkImageCreateInfo::flags containing IMAGE_CREATE_CORNER_SAMPLED_BIT_NV sampled as a result of this command must only be sampled using a VkSamplerAddressMode of SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE.
• For each set n that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a descriptor set must have been bound to n at the same pipeline bind point, with a VkPipelineLayout that is compatible for set n, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• For each push constant that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a push constant value must have been set for the same pipeline bind point, with a VkPipelineLayout that is compatible for push constants, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• Descriptors in each bound descriptor set, specified via vkCmdBindDescriptorSets, must be valid if they are statically used by the VkPipeline bound to the pipeline bind point used by this command
• A valid pipeline must be bound to the pipeline bind point used by this command
• If the VkPipeline object bound to the pipeline bind point used by this command requires any dynamic state, that state must have been set for commandBuffer
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used to sample from any VkImage with a VkImageView of the type IMAGE_VIEW_TYPE_3D, IMAGE_VIEW_TYPE_CUBE, IMAGE_VIEW_TYPE_1D_ARRAY, IMAGE_VIEW_TYPE_2D_ARRAY or IMAGE_VIEW_TYPE_CUBE_ARRAY, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions with ImplicitLod, Dref or Proj in their name, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions that includes a LOD bias or any offset values, in any shader stage
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a uniform buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a storage buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If commandBuffer is an unprotected command buffer, any resource accessed by the VkPipeline object bound to the pipeline bind point used by this command must not be a protected resource
• The current render pass must be compatible with the renderPass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• The subpass index of the current render pass must be equal to the subpass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• Every input attachment used by the current subpass must be bound to the pipeline via a descriptor set
• Image subresources used as attachments in the current render pass must not be accessed in any way other than as an attachment by this command.
• If the draw is recorded in a render pass instance with multiview enabled, the maximum instance index must be less than or equal to VkPhysicalDeviceMultiviewProperties::maxMultiviewInstanceIndex.
• If the bound graphics pipeline was created with VkPipelineSampleLocationsStateCreateInfoEXT::sampleLocationsEnable set to TRUE and the current subpass has a depth/stencil attachment, then that attachment must have been created with the IMAGE_CREATE_SAMPLE_LOCATIONS_COMPATIBLE_DEPTH_BIT_EXT bit set
• All vertex input bindings accessed via vertex input variables declared in the vertex shader entry point’s interface must have valid buffers bound
• For a given vertex buffer binding, any attribute data fetched must be entirely contained within the corresponding vertex buffer binding, as described in Vertex Input Description
• If buffer is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object
• buffer must have been created with the BUFFER_USAGE_INDIRECT_BUFFER_BIT bit set
• offset must be a multiple of 4
• commandBuffer must not be a protected command buffer
• If countBuffer is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object
• countBuffer must have been created with the BUFFER_USAGE_INDIRECT_BUFFER_BIT bit set
• countBufferOffset must be a multiple of 4
• The count stored in countBuffer must be less than or equal to VkPhysicalDeviceLimits::maxDrawIndirectCount
• stride must be a multiple of 4 and must be greater than or equal to sizeof(VkDrawIndexedIndirectCommand)
• If maxDrawCount is greater than or equal to 1, (stride × (maxDrawCount - 1) + offset + sizeof(VkDrawIndexedIndirectCommand)) must be less than or equal to the size of buffer
• If count stored in countBuffer is equal to 1, (offset + sizeof(VkDrawIndexedIndirectCommand)) must be less than or equal to the size of buffer
• If count stored in countBuffer is greater than 1, (stride × (drawCount - 1) + offset + sizeof(VkDrawIndexedIndirectCommand)) must be less than or equal to the size of buffer

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• buffer must be a valid VkBuffer handle
• countBuffer must be a valid VkBuffer handle
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• This command must only be called inside of a render pass instance
• Each of buffer, commandBuffer, and countBuffer must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Inside	Graphics	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

buffer - the buffer containing draw parameters.

offset - the byte offset into buffer where parameters begin.

countBuffer - the buffer containing the draw count.

countBufferOffset - the byte offset into countBuffer where the draw count begins.

maxDrawCount - specifies the maximum number of draws that will be executed. The actual number of executed draw calls is the minimum of the count specified in countBuffer and maxDrawCount.

stride - the byte stride between successive sets of draw parameters.