（Unity）如何将数据（Vector3和Color32）烘焙到渲染纹理上？

Question

随着最近的VFX Graph的引入，属性贴图被用于'从贴图设置位置/颜色'。

为了获得属性贴图，必须将位置和颜色数据烘焙到渲染纹理中。但是没有提到如何做到这一点，甚至在Unity文档中也没有。

将提供任何有关此操作的帮助！

Answer 1

大多数情况下，您想使用Compute Shader将一连串的点烘焙到纹理中。我建议您检查这些存储库以供参考：

将蒙皮的网格渲染器数据烘焙到纹理中https://github.com/keijiro/Smrvfx

将Kinect数据烘焙到纹理中https://github.com/roelkok/Kinect-VFX-Graph

将pointcloud数据烘焙为纹理：https://github.com/keijiro/Pcx

就我个人而言，尽管我不是Compute Shaders的专家，我仍在使用这些脚本以达到我的目的。]

public class FramePositionBaker
{


ComputeShader bakerShader;

RenderTexture VFXpositionMap;

RenderTexture inputPositionTexture;

private ComputeBuffer positionBuffer;

const int texSize = 256;

public FramePositionBaker(RenderTexture _VFXPositionMap)
{

    inputPositionTexture = new RenderTexture(texSize, texSize, 0, RenderTextureFormat.ARGBFloat);

    inputPositionTexture.enableRandomWrite = true;

    inputPositionTexture.Create();

    bakerShader = (ComputeShader)Resources.Load("FramePositionBaker");

    if (bakerShader == null)
    {
        Debug.LogError("[FramePositionBaker] baking shader not found in any Resources folder");
    }

    VFXpositionMap = _VFXPositionMap;

}



public void BakeFrame(ref Vector3[] vertices)
{

    int pointCount = vertices.Length;

    positionBuffer = new ComputeBuffer(pointCount, 3 * sizeof(float));

    positionBuffer.SetData(vertices);

    //Debug.Log("Length " + vertices.Length);

    bakerShader.SetInt("dim", texSize);

    bakerShader.SetTexture(0, "PositionTexture", inputPositionTexture);

    bakerShader.SetBuffer(0, "PositionBuffer", positionBuffer);

    bakerShader.Dispatch(0, (texSize / 8) + 1, (texSize / 8) + 1, 1);

    Graphics.CopyTexture(inputPositionTexture, VFXpositionMap);

    positionBuffer.Dispose();


}

}
计算着色器：

// Each #kernel tells which function to compile; you can have many kernels
#pragma kernel CSMain

// Create a RenderTexture with enableRandomWrite flag and set it
// with cs.SetTexture
RWTexture2D<float4> PositionTexture;

uint dim;

Buffer<float3> PositionBuffer;

[numthreads(8,8,1)]
void CSMain (uint3 id : SV_DispatchThreadID)
{
// TODO: insert actual code here!

uint index = id.y * dim + id.x;

uint lastIndex = PositionBuffer.Length - 1;

// Trick for generating a pseudo-random number.
// Inspired by a similar trick in Keijiro's PCX repo (BakedPointCloud.cs). 
// The points that are in excess because of the square texture, point randomly to a point in the texture.
// e.g. if (index > lastIndex) index = 0 generates excessive particles in the first position, resulting in a visible artifact.

//if (index > lastIndex) index = ( index * 132049U ) % lastIndex;

float3 pos;

if (index > lastIndex && lastIndex != 0) {

    //pos = 0;
    index = ( index * 132049U ) % lastIndex;
}


    pos = PositionBuffer[index];

PositionTexture[id.xy] = float4 (pos.x, pos.y, pos.z, 1);
}