Show backfaces

[SolidModeler]

Hi,

Some of the meshes I get that were made from point clouds don't always have proper normals, and of course the results are that those textured faces don't get displayed by default in some viewers. 3DHOP displays those backfaces as red, and also has a nice feature backfaceColor : [1.0, 1.0, 1.0, 0.0] causing the faces to be displayed with their textures. This was great both because I didn't need to rebuild normals, and the nxs and nsz files made using nxsbuild were smaller when omitting the normals. And so far, it doesn't seem to be hampering viewing performance.
That said, I then tried using the same models with the three.js-related files that are available here. That's where I got stumped.
Do I need to provide some three syntax to display the textured backfaces? Or is there perhaps a way for nexus to trick three into displaying them?

Hope this isn't a dumb question, and thanks for any help.