Graphics tools for visualizer (lines, coordinate frames, primitives, etc)

[jstmn]

Howdy,

I was playing around with the sapien rendering methods and it turns out it's not too bad to add lines to the visualizer. I was thinking it would be cool to add support for visualizing paths / transforms / etc in the gui. For example, in this image there are different paths the end effector can take shown:

Adding support for lines and transforms would be nice.

Thoughts?

[StoneT2000]

would appreciate a PR suggesting a api design for this! I think isaac also has one already, may be a good reference

[jstmn]

Done! I've updated python/py_package/utils/viewer/viewer.py in SAPIEN with some new features.

For testing: #1343
The changes: haosulab/SAPIEN#274

I think having everything in the viewer class will keep things simple. Users usually have a viewer object in their files so there won't be any additional imports required. Some things to consider:

1. Are we happy with the naming convention? The current objects are named box, aabb which are standard. The ones I added are 3d_point_list and coordinate_frame. 3d_point_list is simply a list of 3D points. coordinate_frame is a coordinate frame as the name suggests.
2. Are there any other primitives we should add? The others that are supported are cylinders, cones, capsule, and spheres. I don't need any of these in my work fwiw.

btw, do you want to keep the conversation here, or move to one of the PR comments

[StoneT2000]

Lets move to the PR for SAPIEN. I'll let fanbo make the decisions over there on this, the sapien PR seems good though in terms of naming. I guess 3d_point_list "feels awkward," but I can't formulate the feeling into concrete reasoning, probably fine.

For other primitives feel free to add whatever! I think usually the other shapes would normally just be visual shapes someone adds to an env, but i do see some use-case for these if someone is using a prebuilt env and can't modify it.