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      LunarG has released new Vulkan SDKs for Windows, Linux, and macOS based on the 1.1.73 header. The new SDK includes:
      New extensions: VK_ANDROID_external_memory_android_hardware_buffer VK_EXT_descriptor_indexing VK_AMD_shader_core_properties VK_NV_shader_subgroup_partitioned Many bug fixes, increased validation coverage and accuracy improvements, and feature additions Developers can download the SDK from LunarXchange at https://vulkan.lunarg.com/sdk/home.

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    • By khawk
      LunarG has released new Vulkan SDKs for Windows, Linux, and macOS based on the 1.1.73 header. The new SDK includes:
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Vulkan Vulkan: d24_unorm_s8 support optional?

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According to the Vulkan gpu info website and testing amd doesn't support the d24_unorm_s8_uint format.

At the hardware level it is know that d24_x8 format on dx and OGL is stored in 2 buffers, one 32bits storing depth and one 8 bits storing stencil values. However it's likely that the rop are still emitting 24 bits values leaving 8 undefined bits in the depth buffer to ensure compatibility.

However it looks like current Vulkan drivers doesn't want to emulate this behavior anymore. A d32_sfloat_u8 is available but float and int distribution are not the same. Is the spec leaving d24_x8 format optional or is it due to drivers being pre-release atm?

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At the hardware level it is know that d24_x8 format on dx and OGL is stored in 2 buffers, one 32bits storing depth and one 8 bits storing stencil values
This is up to the GPU. It will usually be a 32bit buffer containing 24bit depth with 8 wasted bits, and a separate 8bit buffer for stencil.

Returning an actual 32bit depth buffer when the user asked for a 24bit one is an error, and isn't allowed in D3D.

 

Modern GPU's want to drop support for the 24bit mode, because it's a waste of sillicon. It's easier for them to just support 32bit depth + 8bit stencil only... So I would guess that they're getting their way with Vulkan now.

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