For any mesh supporting the parameter sideOrientation, we can now pass two extra parameters frontUVs and backUVs both Vector4. These values are taken in account only for double-sided meshes.
They allow to declare what part of the image to crop and stick respectively on the mesh front and back faces.
// set the rectangle coordinates (u0,v0) and (u1,v1) from where to crop the image as a Vector4(u0,v0,u1,v1)
var f = new BABYLON.Vector4(0,0, 0.5, 1); // front image = half the whole image along the width
var b = new BABYLON.Vector4(0.5,0, 1, 1); // back image = second half along the width
var options = {sideOrientation: BABYLON.Mesh.DOUBLESIDE, frontUVs: f, backUVs: b};
// this plane has half the image on the front side and the next half on the back side
var plane = BABYLON.MeshBuilder.CreatePlane("p", options, scene);
// this sphere has half the image on the external side and the next half on the inside side
var sphere = BABYLON.MeshBuilder.CreateSphere("s", options, scene);
A single texture/material but the ability to display different images on each mesh side.
Default values if not passed for both : (0,0, 1,1)