Casting my mind back, TC also used to have a format for something called 'Bitstream' or similar, which was a viewing format for a viewer called 'Viewpoint'. It wasn't bad, but anything that needs plugins (which it did) or standalone viewers is probably going to meet resistance, which is one of the reasons that VRML faded, though it's quite good in Parallel Graphics' Cortona plugin, which is still available. There's a format still in its early days called WebGL, which is a standardised 3D format that can be viewed and manipulated in an HTML5 browser, Firefox and Chrome, not sure about IE, it wasn't last time I tried. I've an idea that iOS browser can, too. Firefox and Chrome can also view TC's .svgs, too. The open-source CAD app FreeCAD is great as a viewer in its own right with STEP (colours carry but not materials) and IGES, but it also has some capability to produce WebGL, which I'm dabbling with ATM.