simtk.org

Hi, I've bashed my head against the wall enough trying to solve this so maybe the forum can?

OpenSim 3.3 models normally open fine in 4.0 for me. We've made a new model that also opens fine in 3.3 but in 4.0 when it loads it shows nothing in the visualizer (not even a blank area where a model should be; just the default OpenSim welcome screen), and the Coordinates tab says "Model: No Models". I am baffled. See testmodel.jpg screencap here. But the Navigator shows that everything in the model is there; e.g. I can see joints, geometry files, etc. No geometry is hidden; all is on "Show". No error messages occur on loading the model.

What could be wrong? I've scrutinized the xml code and don't see clear issues vs. models that work. The bones used are .objs and they visualize OK in OpenSim 3.3 and in Meshlab so it doesn't seem to be a bone graphics issue, which was my first guess.

Thanks
-John Hutchinson

Hi John,

My guess would be that the code that tries to generate the visualization fails, resulting in nothing being sent to the visualizer at all! If you can send me the model file, if not available publicly, that would be great. You can check if it's the mesh files by copying the model file to another folder so it can't find them or renaming your custom Geometry folder. Version 4.0 uses the SimTK parsers for mesh files rather than vtk's parsers (since we don't use vtk anymore for visualization) unfortunately a side effect is that some old mesh files that used to work in 3.3 may not work as is in version 4.0. We plan to utilize the parsers from our new visualizer in the future so keep an eye.

Best regards,
-Ayman

Thanks for the help, Ayman! And the emails. The problem was indeed the OBJs and a simple issue of them being too many MB in size, so decimating them resolved that and all is well in the world again (on a very localized scale). I am posting this followup so that others might learn of this (now obvious and sensible to me but it wasn't earlier) issue and an easy fix/prevention.