I rendered some UV unwrapped raw mesh data using a special shader, and Graphics.DrawMesh() to a render texture, but upon inspection the data is wrong (world normal and position).
- Left is a vanilla unlit shader modified to output the world normal from the game objects, normals align to the unity basis show in the upper right corner.
- Right is the target complex shader that use raw mesh with custom matrix, uv unwrap rendered to texture and read back as texture on the gameobject by another shader (the working is out of scope, context is roughly lightmap as a G buffer)
It seems to make sense since I'm bypassing the gameobject construct of Unity, therefore I have faulty matrix. Therefore, I tried passing my own matrix. But the worldnormal data don't seem to match, and doing the inverse of the transpose of my own matrix doesn't seem to do the trick (the standard stuff to transform normal) ...
To investigate further, as I suspect that raw mesh is the imported data before Unity applies its import settings, I created a little program that I attached to the game object to compare its render to various DrawMesh() commands ... but DrawMesh doesn't work as intended ...
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class MeshVsObjectNormalTest : MonoBehaviour
{
//public GameObject normalObject;
Mesh[] rawMesh;
Matrix4x4 objectMatrix;
Camera cam;
Material mat;
// Start is called before the first frame update
void Start()
{
rawMesh = new Mesh[1];
rawMesh[0] = this.GetComponent<MeshFilter>().mesh;
objectMatrix = Matrix4x4.identity;
cam = Camera.main;
mat = this.GetComponent<Renderer>().material;
}
// Update is called once per frame
//void Update()
void LateUpdate()
//void OnPostRender()
{
//Graphics.DrawMesh(rawMesh[0], objectMatrix, mat,0, cam);
//Graphics.DrawMesh(rawMesh[0], Vector3.zero, Quaternion.identity, mat,0, cam);
Graphics.DrawMesh(rawMesh[0], Vector3.zero, Quaternion.identity, mat,0);
//mat.SetPass(0);
//Graphics.DrawMeshNow(rawMesh[0], objectMatrix);
Debug.Log(cam);
}
}
Nothing shows up, but it's how every example I can find when I search does it, and I'm already using that command successfully to render to texture ...
Is there something I'm missing?
