LightProbes.CalculateInterpolatedLightAndOcclusionProbes

参数

描述

在给定的世界空间位置计算光探针和遮挡探针。

如果场景中没有烘焙探针，则环境探针将写入到 lightProbes 数组，Vector4 (1,1,1,1) 将写入到 occlusionProbes 数组。
如果 positions 为 null，则会抛出 ArgumentNullException。
您可以通过将 null 传递给函数来省略 lightProbes 或 occlusionProbes 数组，但不能同时省略两者。如果两个数组都被省略，则会抛出 ArgumentException。为了获得更好的性能，应该一起计算 lightProbes 和 occlusionProbes。
对于将数组作为参数的重载，lightProbes 和 occlusionProbes 必须至少与 positions 数组具有相同数量的元素。
对于将列表作为参数的重载，如果给定列表中没有足够的空间，则输出列表的大小将调整为适合 positions 数组的大小。
返回的探针可通过 MaterialPropertyBlock.CopySHCoefficientArraysFrom 和 MaterialPropertyBlock.CopyProbeOcclusionArrayFrom 将其复制到 MaterialPropertyBlock 对象，从而进一步用于实例化渲染。

using UnityEngine;

// This script uses OnPreCull for the rendering. It is mandatory to put the script to a Camera object.
// Make sure light probes are placed and baked in the Scene.
// Use Shadowmask mode and mixed lights to see occlusion probes approximating shadowness.
[RequireComponent(typeof(Camera))]
public class Simple : MonoBehaviour
{
    public Material material;

    private Matrix4x4[] transforms;
    private MaterialPropertyBlock properties;
    private Mesh cubeMesh;

    void Start()
    {
        const int kCount = 100;

        // Generate 100 random positions
        var positions = new Vector3[kCount];
        for (int i = 0; i < kCount; ++i)
            positions[i] = new Vector3(Random.Range(-20.0f, 20.0f), Random.Range(-20.0f, 20.0f), Random.Range(-20.0f, 20.0f));

        // Calculate probes at these positions
        var lightprobes = new UnityEngine.Rendering.SphericalHarmonicsL2[kCount];
        var occlusionprobes = new Vector4[kCount];
        LightProbes.CalculateInterpolatedLightAndOcclusionProbes(positions, lightprobes, occlusionprobes);

        // Put them into the MPB
        properties = new MaterialPropertyBlock();
        properties.CopySHCoefficientArraysFrom(lightprobes);
        properties.CopyProbeOcclusionArrayFrom(occlusionprobes);

        // Compute the transforms list
        transforms = new Matrix4x4[kCount];
        for (int i = 0; i < kCount; ++i)
            transforms[i] = Matrix4x4.Translate(positions[i]);

        // Create the cube mesh
        cubeMesh = GameObject.CreatePrimitive(PrimitiveType.Cube).GetComponent<MeshFilter>().sharedMesh;

        // Make sure the material property is assigned
        if (material == null || !material.enableInstancing)
            Debug.LogError("material must be assigned with one with instancing enabled.");
    }

    // OnPreCull happens before every culling, which is the perfect timing to inject DrawMesh* function calls.
    void OnPreCull()
    {
        if (material != null && material.enableInstancing)
        {
            RenderParams rp = new RenderParams(material)
            {
                matProps = properties,
                lightProbeUsage = UnityEngine.Rendering.LightProbeUsage.CustomProvided, // enable instancing for probes
                shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.On,
                receiveShadows = true
            };
            Graphics.RenderMeshInstanced(rp, cubeMesh, 0, transforms);
        }
    }
}

该示例演示了如何利用烘焙的光探针来提升实例化渲染的视觉质量。