How to create/make UV coordinates for polyhedron I am using Blender version 2.74 and I am using an OpenSCAD file someone else made. I am new to Blender.

The OpenSCAD file comes from this website:
http://kitwallace.co.uk/3d/solid-to-scad.xq?id=Tetrahedron&amp;scad=shell
I picked "engrave" for the OpenSCAD option.

I am trying to create UV coordinates for the shape after I import the OpenSCAD file in Blender, so that I can dynamically display a unique image on each face of the tetrahedron as an exported or "finished" JSON file using JavaScript. Whether I export into whatever format using some type of technology such as JavaScript - I don't know if that part is relevant. But the question I have is how to compute/make the UV coordinates for this shape in Blender to make this eventually happen.

Below is the JSON file, the blend file couldn't be shown in text format:

{
    "name": "Tetrahedron.001Geometry",
    "uvs": [],
    "faces": [32,0,1,2,0,1,2,32,3,2,1,3,2,1,32,3,0,2,3,0,2,32,3,1,0,3,1,0],
    "vertices": [-2.42416,0,4.19877,-2.42416,-0,-4.19877,4.84832,0,-0,-0,6.85655,-0],
    "metadata": {
        "type": "Geometry",
        "version": 3,
        "vertices": 4,
        "generator": "io_three",
        "faces": 4,
        "uvs": 0,
        "normals": 4
    },
    "normals": [-0.471389,-0.333323,0.816492,-0.471389,-0.333323,-0.816492,0.942808,-0.333323,0,0,1,0]
}
You can unwrap the tetrahedron in one of 2 ways:


You can create seams (CTRL+E > Mark Seams) running along the 3 edges from the base to the tip. Then select all vertices and press U > UV Unwrap.






You can create seams on all edges  (CTRL+E >Mark Seams) , and overlay each uv island on top of itself. Then select all vertices and press U > UV Unwrap.





Please note the tetrahedron shape in my example is an approximate shape only in order to demonstrate the unwrap technique.