o3de/Gems/AtomTressFX/Assets/Passes/HairParentShortCutPass.pass

{
    "Type": "JsonSerialization",
    "Version": 1,
    "ClassName": "PassAsset",
    "ClassData": {
        "PassTemplate": {
            "Name": "HairParentShortCutPassTemplate",
            "PassClass": "ParentPass",
            "Slots": [
                {
                    "Name": "RenderTargetInputOutput",
                    "SlotType": "InputOutput",
                    "ScopeAttachmentUsage": "RenderTarget"
                },
                { 
                    // used for copy from MSAA to regular RT
                    "Name": "RenderTargetInputOnly",
                    "SlotType": "Input",
                    "ScopeAttachmentUsage": "Shader"
                },
                // This is the depth stencil buffer that is to be used by the fill pass
                // to early reject pixels by depth and in the resolve pass to write the 
                // the hair depth 
                {
                    "Name": "Depth",
                    "SlotType": "InputOutput",
                    "ScopeAttachmentUsage": "DepthStencil"
                },
                // Used to set the size of the Head PPLL image buffer.
                {
                    "Name": "DepthLinear",
                    "SlotType": "InputOutput"
                },

                // Lights & Shadows resources
                {
                    "Name": "DirectionalShadowmap",
                    "SlotType": "Input"
                },
                {
                    "Name": "DirectionalESM",
                    "SlotType": "Input"
                },
                {
                    "Name": "ProjectedShadowmap",
                    "SlotType": "Input"
                },
                {
                    "Name": "ProjectedESM",
                    "SlotType": "Input"
                },
                {
                    "Name": "TileLightData",
                    "SlotType": "Input"
                },
                {
                    "Name": "LightListRemapped",
                    "SlotType": "Input"
                }
            ],
            "PassRequests": [
                {
                    "Name": "HairGlobalShapeConstraintsComputePass",
                    "TemplateName": "HairGlobalShapeConstraintsComputePassTemplate",
                    "Enabled": true
                },
                {
                    "Name": "HairCalculateStrandLevelDataComputePass",
                    "TemplateName": "HairCalculateStrandLevelDataComputePassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairGlobalShapeConstraintsComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        }
                    ]
                },
                {
                    "Name": "HairVelocityShockPropagationComputePass",
                    "TemplateName": "HairVelocityShockPropagationComputePassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairCalculateStrandLevelDataComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        }
                    ]
                },
                {
                    "Name": "HairLocalShapeConstraintsComputePass",
                    "TemplateName": "HairLocalShapeConstraintsComputePassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairVelocityShockPropagationComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        }
                    ]
                },
                {
                    "Name": "HairLengthConstraintsWindAndCollisionComputePass",
                    "TemplateName": "HairLengthConstraintsWindAndCollisionComputePassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairLocalShapeConstraintsComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        }
                    ]
                },
                {
                    "Name": "HairUpdateFollowHairComputePass",
                    "TemplateName": "HairUpdateFollowHairComputePassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairLengthConstraintsWindAndCollisionComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        }
                    ]
                },

                // Render Target Copy from MS to Regular
                {
                    "Name": "RenderTargetCopyPass",
                    "TemplateName": "FullscreenCopyTemplate",
                    "Connections": [
                        {
                            "LocalSlot": "Input",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "RenderTargetInputOnly"
                            }
                        },
                        {
                            "LocalSlot": "Output",
                            "AttachmentRef": {
                                "Pass": "This",
                                "Attachment": "Output"
                            }
                        }
                    ],
                    "ImageAttachments": [
                        {
                            "Name": "Output",
                            "SizeSource": {
                                "Source": {
                                    "Pass": "This",
                                    "Attachment": "Input"
                                }
                            },
                            "FormatSource": {
                                "Pass": "This",
                                "Attachment": "Input"
                            },
                            "GenerateFullMipChain": false
                        }
                    ]
                },

                // Rendering Passes
                {
                    "Name": "HairShortCutGeometryDepthAlphaPass",
                    "TemplateName": "HairShortCutGeometryDepthAlphaPassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairUpdateFollowHairComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        },
                        {
                            "LocalSlot": "Depth",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "Depth"
                            }
                        },
                        {
                            "LocalSlot": "InverseAlphaRTOutput",
                            "AttachmentRef": {
                                "Pass": "This",
                                "Attachment": "InverseAlphaRTOutput"
                            }
                        },
                        {
                            "LocalSlot": "HairDepthsTextureArray",
                            "AttachmentRef": {
                                "Pass": "This",
                                "Attachment": "HairDepthsTextureArray"
                            }
                        }
                    ]
                },

                {
                    "Name": "HairShortCutResolveDepthPass",
                    "TemplateName": "HairShortCutResolveDepthPassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "Depth",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "Depth"
                            }
                        },
                        {
                            "LocalSlot": "HairDepthsTextureArray",
                            "AttachmentRef": {
                                "Pass": "HairShortCutGeometryDepthAlphaPass",
                                "Attachment": "HairDepthsTextureArray"
                            }
                        }
                    ]
                },

                {
                    "Name": "HairShortCutGeometryShadingPass",
                    "TemplateName": "HairShortCutGeometryShadingPassTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "HairColorRenderTarget",
                            "AttachmentRef": {
                                "Pass": "This",
                                "Attachment": "HairColorRenderTarget"
                            }
                        },
                        {
                            // The final render target - this is MSAA mode RT - would it be cheaper to
                            // use non-MSAA and then copy?
                            "LocalSlot": "RenderTargetInputOutput",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "RenderTargetInputOutput"
                            }
                        },
                        {
                            "LocalSlot": "DepthLinear",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "DepthLinear"
                            }
                        },
                        {
                            "LocalSlot": "AccumulatedInverseAlpha",
                            "AttachmentRef": {
                                "Pass": "HairShortCutGeometryDepthAlphaPass",
                                "Attachment": "InverseAlphaRTOutput"
                            }
                        },
                        {
                            "LocalSlot": "Depth",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "Depth"
                            }
                        },
                        {
                            "LocalSlot": "SkinnedHairSharedBuffer",
                            "AttachmentRef": {
                                "Pass": "HairUpdateFollowHairComputePass",
                                "Attachment": "SkinnedHairSharedBuffer"
                            }
                        },

                        // Shadows resources
                        {
                            "LocalSlot": "DirectionalShadowmap",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "DirectionalShadowmap"
                            }
                        },
                        {
                            "LocalSlot": "DirectionalESM",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "DirectionalESM"
                            }
                        },
                        {
                            "LocalSlot": "ProjectedShadowmap",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "ProjectedShadowmap"
                            }
                        },
                        {
                            "LocalSlot": "ProjectedESM",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "ProjectedESM"
                            }
                        },

                        // Lights Resources
                        {
                            "LocalSlot": "TileLightData",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "TileLightData"
                            }
                        },
                        {
                            "LocalSlot": "LightListRemapped",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "LightListRemapped"
                            }
                        }
                    ]
                },

                {
                    "Name": "HairShortCutResolveColorPass",
                    "TemplateName": "HairShortCutResolveColorPassTemplate",
                    "Enabled": true,
                    "Connections": [
                        { 
                            // The final render target - this is MSAA mode RT - would it be cheaper to
                            // use non-MSAA and then copy?
                            "LocalSlot": "RenderTargetInputOutput",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "RenderTargetInputOutput"
                            }
                        },
                        {
                            "LocalSlot": "AccumulatedInverseAlpha",
                            "AttachmentRef": {
                                "Pass": "HairShortCutGeometryDepthAlphaPass",
                                "Attachment": "InverseAlphaRTOutput"
                            }
                        },
                        {
                            "LocalSlot": "HairColorTexture",
                            "AttachmentRef": {
                                "Pass": "HairShortCutGeometryShadingPass",
                                "Attachment": "HairColorRenderTarget"
                            }
                        }
                    ]
                },

                {
                    // This pass copies the updated depth buffer (now contains hair depth) to linear depth texture
                    // for downstream passes to use. This can be optimized even further by writing into the stencil 
                    // buffer pixels that were touched by HairPPLLResolvePass hence preventing depth update unless
                    // it is hair.
                    "Name": "DepthToDepthLinearPass",
                    "TemplateName": "HairDepthToLinearTemplate",
                    "Enabled": true,
                    "Connections": [
                        {
                            "LocalSlot": "Input",
                            "AttachmentRef": {
                                "Pass": "HairShortCutResolveDepthPass",
                                "Attachment": "Depth"
                            }
                        },
                        {
                            "LocalSlot": "Output",
                            "AttachmentRef": {
                                "Pass": "Parent",
                                "Attachment": "DepthLinear"
                            }
                        }
                    ]
                }

            ]
        }
    }
}