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Descriptor Heap alignment#378

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spencer-lunarg merged 1 commit into
KhronosGroup:mainfrom
spencer-lunarg:spencer-lunarg-heap-alignment
May 14, 2026
Merged

Descriptor Heap alignment#378
spencer-lunarg merged 1 commit into
KhronosGroup:mainfrom
spencer-lunarg:spencer-lunarg-heap-alignment

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@SaschaWillems @ziga-lunarg decided to write up a small section around Alignment, open to any other thoughts around it


Second is when you do descriptor indexing that are non-packed (strided).

image::{images}descriptor_heap_stride_alignment.svg[descriptor_heap_stride_alignment.svg]
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.... ok, so I need to update this VUID-VkDescriptorSetAndBindingMappingEXT-source-11252 forces heapArrayStride to be a multiple of bufferDescriptorSize

the issue I guess is really if the data from something PushData creates a bad address

Comment thread chapters/descriptor_heap.adoc Outdated

== Alignment

One of the hardest issues making an application portal across vendors is mastering the art of alignment.
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portal => portable?

ziga-lunarg
ziga-lunarg previously approved these changes May 8, 2026
SaschaWillems
SaschaWillems previously approved these changes May 8, 2026
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LGTM. Some extremely valuable information in here 👍🏻

gpx1000
gpx1000 previously approved these changes May 8, 2026
@spencer-lunarg spencer-lunarg force-pushed the spencer-lunarg-heap-alignment branch from d3e0730 to f6a82ad Compare May 14, 2026 03:22
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added one more example (I realized literally the other day while adding to GPU Dump) how you need to align your indirect UBO/SSBO to minUniformBufferOffsetAlignment/ minStorageBufferOffsetAlignment

@spencer-lunarg spencer-lunarg merged commit 414d8c1 into KhronosGroup:main May 14, 2026
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@spencer-lunarg spencer-lunarg deleted the spencer-lunarg-heap-alignment branch May 14, 2026 03:24
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4 participants