Lightmaps in Three.js

Question

Lightmaps live independently of other textures, right?

So I have to set up a second set of UVs.

I have exported my JSON object with a second set of UVs and added

Answer 1

Lightmaps in three.js require a second set of UVs. One solution is to add a second set of UVs by duplicating the first set.

For THREE.Geometry you can do this:

geometry.faceVertexUvs[ 1 ] = geometry.faceVertexUvs[ 0 ];

For THREE.BufferGeometry, use this pattern;

var uvs = geometry.attributes.uv.array;
geometry.addAttribute( 'uv2', new THREE.BufferAttribute( uvs, 2 ) );

three.js r.73