tree 2f05280fbe15b225da91577e349faed7541b5539
parent 1b1b658d365591b6a8d4bfb0c3524832c89afc99
author Yunchao He <yunchao.he@intel.com> 1639085548 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1639085548 +0000

Implement readonly depth/stencil attachment on Vulkan

It requires to revise quite a few flags in order to implement
readonly depth/stencil attachment on Vulkan. For example:
  - VkAccessFlags,
  - VkPipelineStageFlags,
  - VkImageUsageFlags,
  - and the most important: VkImageLayout.

These revised flags need to be applied to many Vulkan objects.
For examples:
  - VkImageMemoryBarriers,
  - IMAGE_LAYOUT revisions in descriptor set (bindings),
    render pass, and subpass,
  - and loadOp/storeOp revisions in render pass and subpass.

This change also does some workarounds in order to make Vulkan
validation layers happy. For example:
  - use DEPTH_STENCIL_READ_ONLY image layout for binding a
    depth/stencil texture,
  - add DEPTH_STENCIL_ATTACHMENT_BIT image usage for binding a
    depth/stencil texture.

Note that STORE_OP_STORE is used for depth/stencil's storeOp for
readonly attachment. It leads to Vulkan validation error. This
change igores that error and let it proceeds and it works well.

Bug: dawn:485
Change-Id: Ie247c9cbffbd837984b0933a905632ab5ad8862d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/70280
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Yunchao He <yunchao.he@intel.com>