Generating a Mesh and Projectors

Unity Engine
1

hey all…I am wondering about generating meshes. The scenario is a single generated mesh (a quad) and I have an object above it, projecting using the standard ‘light’ projector shader. The projection refuses to go onto my generated quad but will go on anything else in unity that I make from the menu such as the plane. Does this make sense?

I made some buildings in blender and set up a UV map and its fine. I don’t want to create a quad in blender!

eg I have terrain, the projection casts correctly, but not on the quad. A normal box with material? a plane with material? fine…but my plane with same material…no good?

I want to use my single quad code, so I can keep the poly count down

if I cant figure it out by the end of the day, I might end up using a plane, but I would rather figure it out then skip it :wink:
I might actually spit out all the values of the mesh from a plane and my generated mesh…i really need to work this out going forward.

using UnityEngine;
using System.Collections;

public class Person : MonoBehaviour {
	
	public Vector3[] 	newVertices;
	public Vector2[] 	newUV;
	public int[] 		newTriangles;
	public Texture2D[] 	textures;
	public float		fps;
	
	// Use this for initialization
	void Start() 
	{
		Mesh mesh = new Mesh();
		GetComponent<MeshFilter>().mesh = mesh;
		mesh.vertices = newVertices;
		mesh.uv = newUV;
		mesh.triangles = newTriangles;
		mesh.RecalculateNormals();
	}
	
	// Update is called once per frame
	void Update () 
	{
		int index =(int)(Time.time * fps);
		index = index % textures.Length;
		renderer.material.mainTexture = textures[index];
	}
}

is it possible using png 8 textures could cause it? - but my buildings work fine with png 8’s …nope - damn!

2

Do you even see this mesh on the screen?
It looks like you havent set up any coords for verts/tri/uv/renderer, looks like its all null.
Do you have other code we dont see here.

Code snipped from one of my classes
it makes a square with a square hole in it

These UV coords just point to a single point to get the color there.

 // verts for BRUSH1
  static Vector3[] verts = new Vector3[] { new Vector3(-.45f, .02f, .45f),
                                           new Vector3( .45f, .02f, .45f),
                                           new Vector3(-.25f, .02f, .25f),
                                           new Vector3( .25f, .02f, .25f),
                                           new Vector3(-.25f, .02f, -.25f),
                                           new Vector3( .25f, .02f, -.25f),
                                           new Vector3(-.45f, .02f, -.45f),
                                           new Vector3( .45f, .02f, -.45f)
                                          };

  static int[] tri = new int[] { 0,1,3,  3,2,0,
                                 1,7,5,  5,3,1,
                                 7,6,4,  4,5,7,
                                 6,0,2,  2,4,6
                                };

  static Vector2[] uv1;
  static Mesh mesh;
  static Vector3[] tempVerts; 


  static BrushFactory()
  {
    // Set up UV1 array
    uv1 = new Vector2[verts.Length];
    tempVerts = new Vector3[verts.Length];

    for (int v = 0; v < verts.Length; v++)
    {
      uv1[v] = new Vector2(.5f , .5f);
    }
  }
3

Thanks for your reply,

I’ll give a screen shot of whats going on.
I am filling in the values on the front screen through the gui in Unity:

In a nutshell a small 1x1 quad, uv mapping fully to cover the quad
So all this script does is generate the animated quad:

Using the same principle to create a large quad that I place a transparent road grid texture on I get the following results from my little projector ‘projecting’ onto the terrain and subsequent generated road quad sitting just above it.

It avoids projection onto my generated quads - that’s the problem right here:

Does that help explain it a bit more?
I am at work so later today I will grab your code and just try it and see what happens and if it ‘receives’ the projection

Thanks again

4

Hi all, for anyone watching just a quick update, turns out its to do with the material shaders - when I use a transparent/diffuse shader on my material and my texture, the projector does what my pictures show, if I use say a straight diffuse material, it reflects the projector correctly!

Does anyone know of this strange problem? Basically using the projector on transparent material? I will search the forums and reply with anything I find.

5

The Transparent/Diffuse shader has the IgnoreProjector tag set to True. Is there any reason why you’re using the transparent shader?

6

Looks like Kuba has got it.

Wow I’ve never seen anyone do all that in the inspector. :slight_smile:
But thats what its there for I guess.
I tend to do everything in code.

7

Hi guys, after much trial and error (and the projector ignoring transparency) it worked after I recently came back to it and changed the shader to transparent/diffuse/cutout. Unfortunate for me is I don’t know enough about shaders to understand why at this stage :slight_smile:
Thank you for your help, it is appreciated.

Hellaeon