2 - Common Problems

These are some common problems with dealing with TP:

Duplicating TPs makes bad materials

If you duplicate a TP you can expect material problems until you use the "UVW Remove" utility to remove the material on the TP and then render one frame (forces TP to rebuild the material tree).

Particles interpenetrate during collisions

Try increasing the voxels for the groups (only available when using SC)

Increase the number of Collision/Contact iterations on the SC operator

Increase the overall TP samples per second (around 3-6 samples per sec is usually good)

GeomInstance particles have bad alignment after caching

The source geo who is picked in the GeomInstance must have its rotation zeroed out or transform reset.

Nesting caches doesn't seem to work

Sometimes when nesting caches it will seem to exclude all particles from the beginning.

Make sure you are caching a time range that contains the frames in the existing cache.

Motion Blur looks wrong

Try setting the camera to use Shutter Angle 178 and Shutter Offset -2

Cannot scrub timeline

I cannot scrub the timeline with TP in the scene…

Override all particle groups to display no meshes and only dots (or whatever, as long as no meshes).

Jump to frames instead, else pulling every frame over the network will indeed be slow.

Copy the cache files locally and update the TP dynsets to point to the local versions (and return them to network when done)

SurfacePos isn't working

The object/particle MUST have a Multi-SO material with as many materials as you are trying to access.

Obj2Particle objects do not appear in TP

The object's Renderable property must be set to True, and did you check Instance Shape?

Groups As Objects do not appear in viewport

Is their layer visible? GaO creates its objects on the current active Layer

Is the particle group Renderable? If not, the GaO will not be visible.

The whole cache disappears during playback before/after a certain frame

Select the dynset in TP and set the "Out of Range Hold Particle" to "<<>>" (to hold pre & post cache values)

Materials look all confused during rendering

Did you right-click the TP dynset and choose "Save Material" after submitting the cache job to the farm?

Or maybe you duplicated the TP? Check if they have the same material on the base TP object.

Particle Age - "Enters Group" doesn't work

The "Enters Group" condition is a tricky one and you should try to avoid it if you can.

It only tests true if the particle enters the group in a Dynamic Set that is above the "Enters Group" condition in the tree and only on the same subframe. That means: if you have a "Enters Group" Condition in your first Dynamic Set and the particle switches to this group in your last Dynamic Set, the "Enters Group" Condition will not test true on the next frame.