2009

Need to know how to do something? Having a problem? Just want to show
off your work? Post your questions to the appropriate forums.
Simulation takes too long.
General tip:
■ Before performing a CPU-intensive operation such as Create Animation
or Reduce Keys, make sure you don't have any object selected in the scene.
Having an object selected during some calculations can force 3ds Max to
evaluate the selected object many times in order to update its UI, slowing
down the calculations.
If the scene is complex but contains independent parts that don't interact
with each other, try adding the objects involved to different collections
and solvers and create the animations independently for each subset,
enabling and disabling the collections and solvers accordingly.
If you are using
Soft Bodies, Cloth, or Rope on page 4024:
■ Try to reduce the complexity of the mesh that flows to the reactor modifier.
For example, you can apply a MeshSmooth modifier on top of the reactor
modifier to render a smooth surface while simulating a simpler one.
■ For soft bodies with complex meshes, using FFD soft bodies on page 4043
can offer better results and decrease the computation time.
■ Unless necessary, do not use the Avoid Self-Intersections option, because
it increases computation time and memory usage significantly.
■ Try to reduce the number of
substeps on page 4085 used in the simulation.
Also try to decrease the number of Internal Steps used by the
Cloth/Soft/Rope collection.
NOTE These steps also reduce the accuracy of the simulation, and can therefore
cause instability.
If you are using rigid bodies on page 3909:
■ For best results when using rigid bodies only, set Utilities panel > reactor
> About rollout > Choose Solver to Havok 3.
■ Reduce the complexity of the geometry used for the rigid bodies. Try using
bounding boxes or sphere, and avoid using non-fixed concave objects. Use
simpler geometry as a
geometry proxy on page 3914 for the object.
4116 | Chapter 16 reactor