// Copyright (c) 2015-2019 Khronos Group. This work is licensed under a // Creative Commons Attribution 4.0 International License; see // http://creativecommons.org/licenses/by/4.0/ [[dispatch]] = Dispatching Commands _Dispatching commands_ (commands with ftext:Dispatch in the name) provoke work in a compute pipeline. Dispatching commands are recorded into a command buffer and when executed by a queue, will produce work which executes according to the bound compute pipeline. A compute pipeline must: be bound to a command buffer before any dispatch commands are recorded in that command buffer. [open,refpage='vkCmdDispatch',desc='Dispatch compute work items',type='protos'] -- :refpage: vkCmdDispatch To record a dispatch, call: include::{generated}/api/protos/vkCmdDispatch.txt[] * pname:commandBuffer is the command buffer into which the command will be recorded. * pname:groupCountX is the number of local workgroups to dispatch in the X dimension. * pname:groupCountY is the number of local workgroups to dispatch in the Y dimension. * pname:groupCountZ is the number of local workgroups to dispatch in the Z dimension. When the command is executed, a global workgroup consisting of [eq]#pname:groupCountX {times} pname:groupCountY {times} pname:groupCountZ# local workgroups is assembled. .Valid Usage **** include::{chapters}/commonvalidity/draw_dispatch_common.txt[] include::{chapters}/commonvalidity/draw_dispatch_nonindirect_common.txt[] * [[VUID-vkCmdDispatch-groupCountX-00386]] pname:groupCountX must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[0] * [[VUID-vkCmdDispatch-groupCountY-00387]] pname:groupCountY must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[1] * [[VUID-vkCmdDispatch-groupCountZ-00388]] pname:groupCountZ must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[2] **** include::{generated}/validity/protos/vkCmdDispatch.txt[] -- [open,refpage='vkCmdDispatchIndirect',desc='Dispatch compute work items using indirect parameters',type='protos'] -- :refpage: vkCmdDispatchIndirect To record an indirect command dispatch, call: include::{generated}/api/protos/vkCmdDispatchIndirect.txt[] * pname:commandBuffer is the command buffer into which the command will be recorded. * pname:buffer is the buffer containing dispatch parameters. * pname:offset is the byte offset into pname:buffer where parameters begin. fname:vkCmdDispatchIndirect behaves similarly to flink:vkCmdDispatch except that the parameters are read by the device from a buffer during execution. The parameters of the dispatch are encoded in a slink:VkDispatchIndirectCommand structure taken from pname:buffer starting at pname:offset. .Valid Usage **** include::{chapters}/commonvalidity/draw_dispatch_common.txt[] include::{chapters}/commonvalidity/draw_dispatch_indirect_common.txt[] * [[VUID-vkCmdDispatchIndirect-offset-00407]] The sum of pname:offset and the size of sname:VkDispatchIndirectCommand must: be less than or equal to the size of pname:buffer **** include::{generated}/validity/protos/vkCmdDispatchIndirect.txt[] -- [open,refpage='VkDispatchIndirectCommand',desc='Structure specifying a dispatch indirect command',type='structs',xrefs='vkCmdDispatchIndirect'] -- The sname:VkDispatchIndirectCommand structure is defined as: include::{generated}/api/structs/VkDispatchIndirectCommand.txt[] * pname:x is the number of local workgroups to dispatch in the X dimension. * pname:y is the number of local workgroups to dispatch in the Y dimension. * pname:z is the number of local workgroups to dispatch in the Z dimension. The members of sname:VkDispatchIndirectCommand have the same meaning as the corresponding parameters of flink:vkCmdDispatch. .Valid Usage **** * [[VUID-VkDispatchIndirectCommand-x-00417]] pname:x must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[0] * [[VUID-VkDispatchIndirectCommand-y-00418]] pname:y must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[1] * [[VUID-VkDispatchIndirectCommand-z-00419]] pname:z must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[2] **** include::{generated}/validity/structs/VkDispatchIndirectCommand.txt[] -- ifdef::VK_VERSION_1_1,VK_KHR_device_group[] [open,refpage='vkCmdDispatchBase',desc='Dispatch compute work items',type='protos'] -- :refpage: vkCmdDispatchBase To record a dispatch using non-zero base values for the components of code:WorkgroupId, call: ifdef::VK_VERSION_1_1[] include::{generated}/api/protos/vkCmdDispatchBase.txt[] endif::VK_VERSION_1_1[] ifdef::VK_VERSION_1_1+VK_KHR_device_group[or the equivalent command] ifdef::VK_KHR_device_group[] include::{generated}/api/protos/vkCmdDispatchBaseKHR.txt[] endif::VK_KHR_device_group[] * pname:commandBuffer is the command buffer into which the command will be recorded. * pname:baseGroupX is the start value for the X component of code:WorkgroupId. * pname:baseGroupY is the start value for the Y component of code:WorkgroupId. * pname:baseGroupZ is the start value for the Z component of code:WorkgroupId. * pname:groupCountX is the number of local workgroups to dispatch in the X dimension. * pname:groupCountY is the number of local workgroups to dispatch in the Y dimension. * pname:groupCountZ is the number of local workgroups to dispatch in the Z dimension. When the command is executed, a global workgroup consisting of [eq]#pname:groupCountX {times} pname:groupCountY {times} pname:groupCountZ# local workgroups is assembled, with code:WorkgroupId values ranging from [eq]#[ptext:baseGroup*, ptext:baseGroup* {plus} ptext:groupCount*)# in each component. flink:vkCmdDispatch is equivalent to `vkCmdDispatchBase(0,0,0,groupCountX,groupCountY,groupCountZ)`. .Valid Usage **** include::{chapters}/commonvalidity/draw_dispatch_common.txt[] * [[VUID-vkCmdDispatchBase-baseGroupX-00421]] pname:baseGroupX must: be less than sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[0] * [[VUID-vkCmdDispatchBase-baseGroupX-00422]] pname:baseGroupX must: be less than sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[1] * [[VUID-vkCmdDispatchBase-baseGroupZ-00423]] pname:baseGroupZ must: be less than sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[2] * [[VUID-vkCmdDispatchBase-groupCountX-00424]] pname:groupCountX must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[0] minus pname:baseGroupX * [[VUID-vkCmdDispatchBase-groupCountY-00425]] pname:groupCountY must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[1] minus pname:baseGroupY * [[VUID-vkCmdDispatchBase-groupCountZ-00426]] pname:groupCountZ must: be less than or equal to sname:VkPhysicalDeviceLimits::pname:maxComputeWorkGroupCount[2] minus pname:baseGroupZ * [[VUID-vkCmdDispatchBase-baseGroupX-00427]] If any of pname:baseGroupX, pname:baseGroupY, or pname:baseGroupZ are not zero, then the bound compute pipeline must: have been created with the ename:VK_PIPELINE_CREATE_DISPATCH_BASE flag. **** include::{generated}/validity/protos/vkCmdDispatchBase.txt[] -- endif::VK_VERSION_1_1,VK_KHR_device_group[]