External Entity Locator

An External Entity Locator is a Golaem Entity that tracks a Maya mesh or group of meshes. The External Entity Locator is taken into account in avoidance when using a Navigation Behavior and in perception and Sensor Channel Operators as a voxelized geometry. This locator has a position (which is obtained for a tracked Maya DAG object) and a radius for avoidance, and a voxel representation which approximates the mapped meshes for perception and sensor ChOps.
 

Creation

  • Golaem Menu: External Entity Locator
  • MEL command: glmExternalEntityLocatorCmd;
If a DAG Object is selected when the external entity locator is created, locator will automatically use this DAG object as tracked object. If several objects are selected, only the first selected object is used.
 
Connections between an external entity locator and its tracked object

Configuration

 
Tracked Object A Maya mesh or group of meshes, tracked in position and orientation. Each mesh must be convex and closed, with its normals pointing outwards, otherwise the voxel approximation might be incorrect.
Max Voxel Per Axis

The maximum voxel count along each axis. The voxels approximate the tracked Maya geometry. 


Example of voxel representation

Radius Mode The radius of the External Entity. It can be computed with different methods:
  • Bounding Box Diagonal/2: half-size of the Maya DAG object bounding box diagonal
  • Greater Bounding Box Size/2: half-size of the greater size of the Maya DAG object bounding box;
  • Smaller Bounding Box Size/2: half-size of the smaller size of the Maya DAG object bounding box
  • Mean Bounding Box Size/2: half-size of the mean size of the Maya DAG object bounding box sides
  • Custom Radius.

 
 
Radius modes, from left to right, top to bottom: Bounding Box Diagonal/2, Greater Bounding Box Size/2, Smaller Bounding Box Size/2, Mean Bounding Box Size/2

Custom Radius If the custom radius is used, this field specifies the radius of the External Entity. This attribute can be keyframed.
Custom Radius If the custom radius is used, this field specifies the height of the External Entity.

Limitations

If the External Entity moves faster than Entities, or if Entities are really constrained, they may not manage to correctly avoid the External Entity: thus, collisions may occur. In that case, Entities will be stopped until the collision ends.