Known limitations

Asset conversion

• Agent type: If you export a skinned mesh from Maya and you want to use it in Houdini, make sure the mesh is triangulated and set  the normals per face.
• Agent type: The skeleton root must be tagged as pelvis.

• Agent type: the viewport skinning preview only supports 3 joint weights per vertex maximum. Please make sure to skin each vertex to 3 joints maximum or the Viewport preview won't display correctly.

• Agent type: (Maya only) your joint local rotation values must always be set to 0 before exporting your skeleton.

• Animation clip: Please make sure the joints between a foot root and the foot ik are animated only on one axis before exporting your animation. Joints animated on more than one axis may not be evaluated properly by Atoms IK with 2 joints.
• Animation clip: Scale compensating is not supported (as in Maya). If you scale a joint all its children will be scaled.

Atoms UI

• When opening the Atoms UI in Houdini on Windows if you get the following error:

Please open the C:\Program Files\Side Effects Software\Houdini $VERSION\python27\lib\mimetypes.py file with a text editor and replace "except UnicodeEncodeError:" (line 250) with "except UnicodeError:"

• When registering FBX anmation clips, please make sure to clamp the last frame of the FBX animation. This is to prevent a bug in FBX which could make disappear your agents playing that clip.

Rendering

• Vray does not work with agent groups. If you want to render with vray you have to cache your simulation and create an AtomsProxy node.
• All render engines. Rendering a group node does not work with motion blur. If you want to use motion blur you have to render from a AtomsProxy node.

Agent overrides

• MAYA: When using python please make sure your agent override plug id is always the same as the "Key" compound child attribute. If these two values will differ, you might experience unpredictable results.
• HOUDINI: Unlike Maya the agent override dialog performances can be quite slow when it comes to agent groups with several thousand agents. This is because the different way Houdini has for handling parms/attributes.

Maya specific

• When using an Alembic geometry as an height field, the geometry will look static for the entire animation. Please import the alembic twice for having a visual feedback of your geometry.

Houdini specific

• The variation builder won't bake the textures for any of the render engines from inside Houdini.