LDrawLoader: colour -> color

[gkjohnson]

Related issue: #23157 (comment)

Description

Convert all variable names and comments with the spelling "colour" to "color" in LDrawLoader.

Also it occurs to me that merging all geometry within a single loaded LDraw hierarchy using BufferGeometryUtils.mergeBufferGeometries is not so straight forward. In order to get an optimal model you need to make sure all faces that share a material are sorted next to each other and grouped. And some of the LDraw meshes will have multiple materials. It would need to be a mesh and material-aware geometry merge which is more complicated than I initially anticiptated so we'll have to revisit that another time.

https://raw.githack.com/gkjohnson/three.js/ldraw-colour-color/examples/webgl_loader_ldraw.html

[yomboprime]

It would need to be a mesh and material-aware geometry merge

Perhaps it would be easier to do it in two steps: First a separation by materials (which should be easy to do), and then merging all geometries of the N materials in N calls to BufferGeometryUtils.mergeBufferGeometries. I don't know if it will be too slow but I think I'll try it.

[mrdoob]

Thanks!