ScriptableRenderContext.DrawRenderers

参数

描述

安排绘制可见对象集，并可选地覆盖 GPU 的渲染状态。

此函数创建用于绘制指定几何体的命令，并将命令添加到 ScriptableRenderContext 的内部命令列表中。当调用 ScriptableRenderContext.Submit 时，ScriptableRenderContext 会执行其内部列表中的所有命令。

此示例演示如何使用 CommandBuffer 清除渲染目标，然后调用此函数绘制几何体。

using UnityEngine;
using UnityEngine.Rendering;

public class ExampleRenderPipeline : RenderPipeline
{
    public ExampleRenderPipeline()
    {
    }

    protected override void Render(ScriptableRenderContext context, Camera[] cameras)
    {
        // Create and schedule a command to clear the current render target
        var cmd = new CommandBuffer();
        cmd.ClearRenderTarget(true, true, Color.black);
        context.ExecuteCommandBuffer(cmd);
        cmd.Release();

        // Iterate over all Cameras
        foreach (Camera camera in cameras)
        {
            // Get the culling parameters from the current Camera
            camera.TryGetCullingParameters(out var cullingParameters);

            // Use the culling parameters to perform a cull operation, and store the results
            var cullingResults = context.Cull(ref cullingParameters);

            // Update the value of built-in shader variables, based on the current Camera
            context.SetupCameraProperties(camera);

            // Tell Unity which geometry to draw, based on its LightMode Pass tag value
            ShaderTagId shaderTagId = new ShaderTagId("ExampleLightModeTag");

            // Tell Unity how to sort the geometry, based on the current Camera
            var sortingSettings = new SortingSettings(camera);

            // Create a DrawingSettings struct that describes which geometry to draw and how to draw it
            DrawingSettings drawingSettings = new DrawingSettings(shaderTagId, sortingSettings);

            // Tell Unity how to filter the culling results, to further specify which geometry to draw
            // Use FilteringSettings.defaultValue to specify no filtering
            FilteringSettings filteringSettings = FilteringSettings.defaultValue;

            // Schedule a command to draw the geometry, based on the settings you have defined
            context.DrawRenderers(cullingResults, ref drawingSettings, ref filteringSettings);

            // Schedule a command to draw the Skybox if required
            if (camera.clearFlags == CameraClearFlags.Skybox && RenderSettings.skybox != null)
            {
                context.DrawSkybox(camera);
            }

            // Instruct the graphics API to perform all scheduled commands
            context.Submit();
        }
    }
}

覆盖渲染状态

使用此函数绘制几何体时，可以使用一个或多个 RenderStateBlock 结构体以以下方式覆盖 GPU 的渲染状态。

• 可以使用 stateBlock 参数提供单个 RenderStateBlock 结构体。Unity 对此函数绘制的所有几何体都使用 stateBlock 中定义的渲染状态。
• 可以使用 stateBlocks 参数提供一个 RenderStateBlock 结构体数组，并使用 renderTypes 参数提供名称为 RenderType 的 SubShader 标签 的值数组。对于 renderTypes 数组中的每个元素，如果 Unity 找到名称为 RenderType 且值匹配的 SubShader 标签几何体，则使用 stateBlocks 数组对应元素中定义的渲染状态。如果有多个匹配项，则 Unity 使用第一个匹配项。如果 renderTypes 数组中的元素具有 ShaderTagId 的默认值，则 Unity 将其视为通配符，并对所有几何体使用相应的渲染状态。
• 可以使用 stateBlocks 参数提供一个 RenderStateBlock 结构体数组，并使用 tagName、tagValues 和 isPassTagName 参数指定任何 SubShader 标签 或 Pass 标签 的名称和值。对于 tagNames 和 tagValues 数组中的每个元素，Unity 会识别具有匹配的 SubShader 标签或 Pass 标签名称和值的几何体，并应用 stateBlocks 数组对应元素中定义的渲染状态。如果有多个匹配项，则 Unity 使用第一个匹配项。如果 tagValues 中的元素具有 ShaderTagId 的默认值，则 Unity 将其视为通配符，并对所有几何体使用相应的渲染状态。

此示例演示如何覆盖渲染状态。

using UnityEngine;
using UnityEngine.Rendering;
using Unity.Collections;

public class OverrideRenderStateExample
{
    ScriptableRenderContext scriptableRenderContext;

    // Override the render state for all geometry that this function draws
    public void OverrideRenderStateForAll(CullingResults exampleCullingResults, DrawingSettings exampleDrawingSettings, FilteringSettings exampleFilteringSettings)
    {
        // Tell Unity how to override the render state
        var stateBlock = new RenderStateBlock(RenderStateMask.Depth);
        stateBlock.depthState = new DepthState(true, CompareFunction.LessEqual);

        // Schedule a command to draw the geometry using the desired render state
        // Unity will execute all scheduled commands during the next call to ScriptableRenderContext.Submit
        scriptableRenderContext.DrawRenderers(exampleCullingResults, ref exampleDrawingSettings, ref exampleFilteringSettings, ref stateBlock);
    }

    // Override the render state for all geometry that has a SubShader Tag
    // with a name of "RenderType" and a value of "ExampleRenderTypeTagValue"
    public void OverrideRenderStateUsingRenderTypeTag(CullingResults exampleCullingResults, DrawingSettings exampleDrawingSettings, FilteringSettings exampleFilteringSettings)
    {
        // Create the parameters that tell Unity how to override the render state
        var stateBlock = new RenderStateBlock(RenderStateMask.Depth);
        stateBlock.depthState = new DepthState(true, CompareFunction.Greater);
        var stateBlocks = new NativeArray<RenderStateBlock>(1, Allocator.Temp);
        stateBlocks[0] = stateBlock;

        // Create the parameters that tell Unity when to override the render state
        ShaderTagId renderType = new ShaderTagId("ExampleRenderTypeTagValue");
        var renderTypes = new NativeArray<ShaderTagId>(1, Allocator.Temp);
        renderTypes[0] = renderType;

        // Schedule a command to draw the geometry using the desired render state
        // Unity will execute all scheduled commands during the next call to ScriptableRenderContext.Submit
        scriptableRenderContext.DrawRenderers(exampleCullingResults, ref exampleDrawingSettings, ref exampleFilteringSettings, renderTypes, stateBlocks);

        // DrawRenderers copies the array contents, so it is safe to dispose of the native arrays
        stateBlocks.Dispose();
        renderTypes.Dispose();
    }

    // Override the render state in two different ways.
    // Use one state for all geometry that has a Pass Tag
    // with a name of "ExamplePassTagName" and a value of "ExamplePassTagValue".
    // For all other geometry, use a second state.
    public void OverrideRenderStateUsingPassTag(CullingResults exampleCullingResults, DrawingSettings exampleDrawingSettings, FilteringSettings exampleFilteringSettings)
    {
        // Create the parameters that tell Unity how to override the render state
        var stateBlock0 = new RenderStateBlock(RenderStateMask.Depth);
        stateBlock0.depthState = new DepthState(true, CompareFunction.Greater);
        var stateBlock1 = new RenderStateBlock(RenderStateMask.Depth);
        stateBlock1.depthState = new DepthState(true, CompareFunction.Less);
        var stateBlocks = new NativeArray<RenderStateBlock>(2, Allocator.Temp);
        stateBlocks[0] = stateBlock0;
        stateBlocks[1] = stateBlock1; // default override

        // Create the parameters that tell Unity when to override the render state
        ShaderTagId tagName = new ShaderTagId("ExamplePassTagName");
        bool isPassTagName = true;
        var tagValues = new NativeArray<ShaderTagId>(2, Allocator.Temp);
        tagValues[0] = new ShaderTagId("ExamplePassTagValue");
        tagValues[1] = new ShaderTagId(); // catch all

        // Schedule a command to draw the geometry using the desired render state
        // Unity will execute all scheduled commands during the next call to ScriptableRenderContext.Submit
        scriptableRenderContext.DrawRenderers(exampleCullingResults, ref exampleDrawingSettings, ref exampleFilteringSettings, tagName, isPassTagName, tagValues, stateBlocks);

        // DrawRenderers copies the array contents, so it is safe to dispose of the native arrays
        stateBlocks.Dispose();
        tagValues.Dispose();
    }
}

其他资源：在自定义 Scriptable Render Pipeline 中创建简单的渲染循环 CullingResults、DrawingSettings、FilteringSettings、RenderStateBlock。