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## Extension and Version Dependencies

• Requires support for Vulkan 1.0

## Contact

• Bill Licea-Kane wwlk

2020-03-25

Contributors
• Bill Licea-Kane, Qualcomm Technologies, Inc.

## Description

Renderpass attachments can be read-only for the duration of a render pass.

Examples include input attachments and depth attachments where depth tests are enabled but depth writes are not enabled.

In such cases, there can be no contents generated for an attachment within the render area.

This extension adds a new VkAttachmentStoreOp VK_ATTACHMENT_STORE_OP_NONE_QCOM specifying that the contents within the render area may not be written to memory, but that the prior contents of the attachment in memory are preserved. However, if any contents were generated within the render area during rendering, the contents of the attachment will be undefined inside the render area.

 Note The VkAttachmentStoreOp VK_ATTACHMENT_STORE_OP_STORE may force an implementation to assume that the attachment was written and force an implementation to flush data to memory or to a higher level cache. The VkAttachmentStoreOp VK_ATTACHMENT_STORE_OP_NONE_QCOM may allow an implementation to assume that the attachment was not written and allow an implementation to avoid such a flush..

## New Enum Constants

• VK_QCOM_RENDER_PASS_STORE_OPS_EXTENSION_NAME

• VK_QCOM_RENDER_PASS_STORE_OPS_SPEC_VERSION

• Extending VkAttachmentStoreOp:

• VK_ATTACHMENT_STORE_OP_NONE_QCOM

## Version History

• Revision 1, 2019-12-20 (wwlk)

• Initial version

• Revision 2, 2020-03-25 (wwlk)

• Minor renaming