How is the image resource for PipelineOutput created?

[ohmaya]

MainPipeline.pass:

            "PassData": {
                "$type": "PassData",
                "PipelineGlobalConnections": [
                    {
                        "GlobalName": "PipelineOutput",
                        "Slot": "PipelineOutput"
                    }
                ]
            },

PipelineOutput is referred to in DepthPrePass request:

                        {
                            "LocalSlot": "PipelineOutput",
                            "AttachmentRef": {
                                "Pass": "PipelineGlobal",
                                "Attachment": "PipelineOutput"
                            }
                        }

And, where is this PipelineGlobal pass defined? Might be a SwapChainPass?

Thanks.

[VickyAtAZ]

"PipelineGlobal" is a special keyword but not a particular pass.
If "PipelineGlobal" is specified, it would look for a the pass connection reference in render pipeline's global connections.
Any pass may add "PipelineGlobalConnections" to their PassData to create a render pipeline global connection from its pass connection.

For example, in o3de\Gems\Atom\Feature\Common\Assets\Passes\DepthParent.pass, the DepthParentTemplate adds 3 pipeline global connections in its PassData. This means, when other pass uses

"AttachmentRef": {
                                "Pass": "PipelineGlobal",
                                "Attachment": "DepthMSAA"
                            }

to reference a pass connection/attachment, it would use DepthParentTemplate's DepthMSAA.

[ohmaya]

Yeah, "const Name PipelineGlobalKeyword{"PipelineGlobal"};". It was just an incidental question for the main question. So, it means the image resource for PipelineOutput is not created in PipelineGlobal pass.

I will think the image resource is created along with the swapchain, then only the attachment is created in SwapChainPass:

m_swapChainAttachment = aznew PassAttachment();
pipelineOutput->SetAttachment(m_swapChainAttachment);

aws-lumberyard-dev@bb0959a#diff-4d68c889c10324f59061914491e1864abfe2533ab3bc248e78a96f5c1a5d6593
This FSR2 integration adds a RenderOutput slot along with PipelineOutput. However, it seems the image for RenderOutput is not created, so if the depth pass refers to RenderOutput, the created depth buffer is of (1, 1, 1).