Any plan for GL_ARM_shader_framebuffer_fetch_depth_stencil?

[梁蕴锋]

Dear developers of ANGLE:

        I have noticed that there is support for GL_ARM_shader_framebuffer_fetch in ANGLE, what about GL_ARM_shader_framebuffer_fetch_depth_stencil. I think it is a useful feature for many use cases. Any plans for that?

Thanks.

[Shahbaz Youssefi]

Hi,

The answer depends on the backend. We've had a similar request for the Vulkan backend, so it might happen there in the near future. I wouldn't count on support in the other backends though, just maybe the GL backend would get it as an easy addition.

I would be interested to know use cases you have in mind for this extension.

Cheers

[梁蕴锋]

Hi,

Thanks for your reply. Looking forward to this feature.

I use it to implement decay rendering on my private game engine. My method includes fetching the current depth value and perform screen space decay.

It would be nice using this extension for the performance.

[Shahbaz Youssefi]

Hi,

FYI, this extension is now implemented for the Vulkan backend of ANGLE. Since there is no non-coherent version of this extension, it is only enabled where the Vulkan driver exposes VK_EXT_rasterization_order_attachment_access with the rasterizationOrderDepth/StencilAttachmentAccess bits. It also relies on VK_KHR_dynamic_rendering. You can expect it to be enabled on very recent ARM (GPU) devices, but it might eventually be enabled on other TBR GPUs too.