Dynamic mesh creation and UVs

Unity Engine
1

Just for making things clear, I’m a developer. I have only minimal knowledge of how 3D texturing works.

In my project I created a dynamic mesh. Everything goes fine, except for UVS: I just cant understand in any way what do UVs do :smile:

In all examples and example projects I found this code useful for assigning values to the UV array:

for(int a=0;a<UVs.Length;a++) 
{ [INDENT]UVs[a] = new Vector2(Verts[a].x,Verts[a].y);// "Verts" is the vertices array
[/INDENT]}

I only understood that there is some relation between the vertices and the UVs (usually the length of UVs is the same as the length of the vertices - and I am using the verices array to initialize the UVs values).

The code works perfectly, but what exactly the above code does? What’s the information stored by the UVs array?
I need to control in more detail the way the mesh is textured.

Thanks for help
Simone

2

The texture UV is an extra component to EACH vertex that defines what coordinate of texture to use. Since x, y, z are used to define it’s position in 3D space, the u, v are to define its texture position in a 2D texture. (0,0) is bottom left (1,1) is top right.

3

Thanks a lot callahan!, now i understand.
I didnt know that the u and v were the relative positions of the textures.

4

In case you’re still interested, the bit of code you posted performs simple planar UV mapping (which is just one of many ways to assign texture coordinates to vertices).

5

Ok thanks. Now I have the knowledge to understand that

Simone