Вступление или пару слов о Render Pipeline

План действий

• отрисовка указанных объектов
• размытие отрисованных объектов
• получение контуров объектов из изображений, полученных на предыдущих проходах

Создаём OutlineFeature

using UnityEngine;
using UnityEngine.Rendering.Universal;

public class OutlineFeature : ScriptableRendererFeature
{
    public override void Create()
    { }

    public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
    { }
}

Render Objects Pass

using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;

public class MyRenderObjectsPass : ScriptableRenderPass
{
    {
        public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
        { }
        public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
        { }
    }
}

Замена цели рендеринга

private RenderTargetHandle _destination;

public MyRenderObjectsPass(RenderTargetHandle destination)
{
    _destination = destination;
}

public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
{  
    cmd.GetTemporaryRT(_destination.id, cameraTextureDescriptor);
}

public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
{        
    cmd.GetTemporaryRT(_destination.id, cameraTextureDescriptor);
    ConfigureTarget(_destination.Identifier());
    ConfigureClear(ClearFlag.All, Color.clear);
}

Рендер

...
private List<ShaderTagId> _shaderTagIdList = new List<ShaderTagId>() { new ShaderTagId("UniversalForward") };
private FilteringSettings _filteringSettings;
private RenderStateBlock _renderStateBlock;
...
public MyRenderObjectsPass(RenderTargetHandle destination, int layerMask)
{
    _destination = destination;

    _filteringSettings = new FilteringSettings(RenderQueueRange.opaque, layerMask);
    _renderStateBlock = new RenderStateBlock(RenderStateMask.Nothing);
}

public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
    SortingCriteria sortingCriteria = renderingData.cameraData.defaultOpaqueSortFlags;
    DrawingSettings drawingSettings = CreateDrawingSettings(_shaderTagIdList, ref renderingData, sortingCriteria);

    context.DrawRenderers(renderingData.cullResults, ref drawingSettings, ref _filteringSettings, ref _renderStateBlock);
}

Замена материала

private Material _overrideMaterial;

public MyRenderObjectsPass(RenderTargetHandle destination, int layerMask,, Material overrideMaterial)
{
...
    _overrideMaterial = overrideMaterial;
...
}

public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
...
    DrawingSettings drawingSettings = CreateDrawingSettings(_shaderTagIdList, ref renderingData, sortingCriteria);
    drawingSettings.overrideMaterial = _overrideMaterial;
...
}

Шейдер для отрисовки

Добавляем проход в OutlineFeature

public class OutlineFeature : ScriptableRendererFeature
{
    [Serializable]
    public class RenderSettings
    {
        public Material OverrideMaterial = null;
        public LayerMask LayerMask = 0;
    }
    ...
}

[SerializeField] private string _renderTextureName;
[SerializeField] private RenderSettings _renderSettings;

private RenderTargetHandle _renderTexture;
private MyRenderObjectsPass _renderPass;

public override void Create()
{
    _renderTexture.Init(_renderTextureName);

    _renderPass = new MyRenderObjectsPass(_renderTexture, _renderSettings.LayerMask, _renderSettings.OverrideMaterial);
}

public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
{
    renderer.EnqueuePass(_renderPass);
}

Blur Pass

using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;

public class BlurPass : ScriptableRenderPass
{
    public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
    { }
}

private int _tmpBlurRTId1 = Shader.PropertyToID("_TempBlurTexture1");
private int _tmpBlurRTId2 = Shader.PropertyToID("_TempBlurTexture2");

private RenderTargetIdentifier _tmpBlurRT1;
private RenderTargetIdentifier _tmpBlurRT2;

private RenderTargetIdentifier _source;
private RenderTargetHandle _destination;

private int _passesCount;
private int _downSample;
private Material _blurMaterial;

public BlurPass(Material blurMaterial, int downSample, int passesCount)
{
    _blurMaterial = blurMaterial;
    _downSample = downSample;
    _passesCount = passesCount;
}

public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
{
    var width = Mathf.Max(1, cameraTextureDescriptor.width >> _downSample);
    var height = Mathf.Max(1, cameraTextureDescriptor.height >> _downSample);
    var blurTextureDesc = new RenderTextureDescriptor(width, height, RenderTextureFormat.ARGB32, 0, 0);

    _tmpBlurRT1 = new RenderTargetIdentifier(_tmpBlurRTId1);
    _tmpBlurRT2 = new RenderTargetIdentifier(_tmpBlurRTId2);

    cmd.GetTemporaryRT(_tmpBlurRTId1, blurTextureDesc, FilterMode.Bilinear);
    cmd.GetTemporaryRT(_tmpBlurRTId2, blurTextureDesc, FilterMode.Bilinear);

    cmd.GetTemporaryRT(_destination.id, blurTextureDesc, FilterMode.Bilinear);
    ConfigureTarget(_destination.Identifier());
}

Размытие

public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
    var cmd = CommandBufferPool.Get("BlurPass");
    ...
    context.ExecuteCommandBuffer(cmd);
    CommandBufferPool.Release(cmd);
}

public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
    var cmd = CommandBufferPool.Get("BlurPass");

    if (_passesCount > 0)
    {
        cmd.Blit(_source, _tmpBlurRT1, _blurMaterial, 0);
        for (int i = 0; i < _passesCount - 1; i++)
        {
            cmd.Blit(_tmpBlurRT1, _tmpBlurRT2, _blurMaterial, 0);
            var t = _tmpBlurRT1;
            _tmpBlurRT1 = _tmpBlurRT2;
            _tmpBlurRT2 = t;
        }
        cmd.Blit(_tmpBlurRT1, _destination.Identifier());
    }
    else
        cmd.Blit(_source, _destination.Identifier());
    context.ExecuteCommandBuffer(cmd);
    CommandBufferPool.Release(cmd);
}

Шейдер

Добавляем проход в OutlineFeature

    [Serializable]
    public class BlurSettings
    {
        public Material BlurMaterial;
        public int DownSample = 1;
        public int PassesCount = 1;
    }

[SerializeField] private string _bluredTextureName;
[SerializeField] private BlurSettings _blurSettings;
private RenderTargetHandle _bluredTexture;
private BlurPass _blurPass;

...

public override void Create()
{
    _bluredTexture.Init(_bluredTextureName);

    _blurPass = new BlurPass(_blurSettings.BlurMaterial, _blurSettings.DownSample, _blurSettings.PassesCount);
}

public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
{
    renderer.EnqueuePass(_renderPass);
    renderer.EnqueuePass(_blurPass);
}

Outline Pass

public class OutlinePass : ScriptableRenderPass
{
    private string _profilerTag = "Outline";
    private Material _material;

    public OutlinePass(Material material)
    {
        _material = material;
    }

    public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
    {
        var cmd = CommandBufferPool.Get(_profilerTag);

        using (new ProfilingSample(cmd, _profilerTag))
        {
            var mesh = RenderingUtils.fullscreenMesh;
            cmd.DrawMesh(mesh, Matrix4x4.identity, _material, 0, 0);
        }

        context.ExecuteCommandBuffer(cmd);
        CommandBufferPool.Release(cmd);
    }
}

Шейдер

Shader "Custom/Outline"
{
    Properties
    {
        _Color ("Glow Color", Color ) = ( 1, 1, 1, 1)
        _Intensity ("Intensity", Float) = 2
        [Enum(UnityEngine.Rendering.BlendMode)] _SrcBlend ("Src Blend", Float) = 1
        [Enum(UnityEngine.Rendering.BlendMode)] _DstBlend ("Dst Blend", Float) = 0
    }
    
    SubShader
    {       
        HLSLINCLUDE
 
        #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
        
        struct Attributes
        {
            float4 positionOS   : POSITION;
            float2 uv           : TEXCOORD0;
        };
        
        struct Varyings
        {
            half4 positionCS    : SV_POSITION;
            half2 uv            : TEXCOORD0;
        };
 
        TEXTURE2D_X(_OutlineRenderTexture);
        SAMPLER(sampler_OutlineRenderTexture);
 
        TEXTURE2D_X(_OutlineBluredTexture);
        SAMPLER(sampler_OutlineBluredTexture);
 
        half4 _Color;
        half _Intensity;
 
        Varyings Vertex(Attributes input)
        {
            Varyings output;
            output.positionCS = float4(input.positionOS.xy, 0.0, 1.0); 
            output.uv = input.uv;
            if (_ProjectionParams.x < 0.0) 
                output.uv.y = 1.0 - output.uv.y;    
            return output;      
        }
 
        half4 Fragment(Varyings input) : SV_Target
        {
            float2 uv = UnityStereoTransformScreenSpaceTex(input.uv);
            half4 prepassColor = SAMPLE_TEXTURE2D_X(_OutlineRenderTexture, sampler_OutlineRenderTexture, uv);
            half4 bluredColor = SAMPLE_TEXTURE2D_X(_OutlineBluredTexture, sampler_OutlineBluredTexture,uv);
            half4 difColor = max( 0, bluredColor - prepassColor);
            half4 color = difColor* _Color * _Intensity;
            color.a = 1;    
            return color;
        }
        
        ENDHLSL        
     
        Pass
        {
            Blend [_SrcBlend] [_DstBlend]
            ZTest Always    // всегда рисуем, независимо от текущей глубины в буфере
            ZWrite Off      // и ничего в него не пишем
            Cull Off        // рисуем все стороны меша
 
            HLSLPROGRAM
           
            #pragma vertex Vertex
            #pragma fragment Fragment        
 
            ENDHLSL         
        }
    }
}

Добавляем проход в OutlineFeature

[SerializeField] private Material _outlineMaterial;
private OutlinePass _outlinePass;

public override void Create()
{
    ...
    _outlinePass = new OutlinePass(_outlineMaterial);
    ....
}

public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
{
    renderer.EnqueuePass(_renderPass);
    renderer.EnqueuePass(_blurPass);
    renderer.EnqueuePass(_outlinePass);
}

RenderPassEvent

[SerializeField] private RenderPassEvent _renderPassEvent;

public override void Create()
{
    ...
    _renderPass.renderPassEvent = _renderPassEvent;
    _blurPass.renderPassEvent = _renderPassEvent;
    _outlinePass.renderPassEvent = _renderPassEvent;
}

Настройка

Результат

Доработка

RenderObjectsPass

public class MyRenderObjectsPass : ScriptableRenderPass
{
    ...
    private RenderTargetIdentifier _depth;

    public void SetDepthTexture(RenderTargetIdentifier depth)
    { _depth = depth; }
    ...
}
В методе Configure() укажем глубину в настройке цели рендера.

<source lang="cs">
public override void Configure(CommandBuffer cmd, RenderTextureDescriptor cameraTextureDescriptor)
{
    cmd.GetTemporaryRT(_destination.id, cameraTextureDescriptor);
    ConfigureTarget(_destination.Identifier(), _depth);
    ConfigureClear(ClearFlag.Color, Color.clear);
}

OutlineFeature

public class OutlineFeature : ScriptableRendererFeature
{
    ...
    public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
    {
        var depthTexture = renderer.cameraDepth;
        _renderPass.SetDepthTexture(depthTexture);

        renderer.EnqueuePass(_renderPass);
        renderer.EnqueuePass(_blurPass);
        renderer.EnqueuePass(_outlinePass);
    }
    ...
}

UniversalRenderPipelineAsset

Результат

Итог

P.S.

Ссылки