The Dynamo Solver object is the core engine of a simulation. All deformable objects and colliders need to be tied to a solver and when the Dynamo modifier is added to an object for the first time in a scene, a solver object is created automatically.
The solver object contains all parameters that concern the simulation and there can, in fact, be several solvers in the scene simultaneously. This could be used to, for instance, simulate secondary objects such as straps or pockets on top of a base simulation.
The settings in the accuracy section affect the precision of the simulation - increasing these settings will result in a more accurate simulation, at the expense of computation time.
This value determines the number of iterations Dynamo performs when trying to solve the constraints of the simulation. The higher this value, the better Dynamo will be able to keep the deformable objects from stretching or bending too far. In practice, increasing the number of iterations allows higher stiffness values in the deformable objects of the simulation.
The number of substeps determine how many segments each frame should be divided into when performing collision detection. If this value is set too low, collisions between fast-moving deformers and colliders can be inaccurate.
Since increasing this value means that more simulation steps are taken in each frame, it will also increase the accuracy of constraints in the same way as increasing the number of iterations.
Based on the iterations, substeps and timeline FPS, the max stiffness value is the maximum achievable setting for the bending and distance stiffness of deformable objects. This means that setting either of the stiffness values in a deformable object higher than this value will have no additional effect. This value will increase when the number of iterations or substeps are increased.
The "Colliders" section contains settings that relate to collisions.
Objects to Include
There are three options regarding which objects to include as colliders in the simulation.
- "Automatic" is the same as "Dynamo objects" if there are any colliders with the Dynamo modifier in the scene, otherwise it is the same as "All objects".
- "All objects" will include all visible objects in the scene as colliders.
- "Dynamo objects" will include only the objects that have a Dynamo modifier set to collider.
This checkbox enables the ground collider. It is more stable than using a plane for ground collisions. The parameters "Kinetic friction" and "Static friction" work identically to how they work in colliders.
This checkbox enables or disables self collisions for all deformable objects in the simulation. When not checked, deformable objects will not collide with other parts of themselves.
The forces section contains a list of all active forces in the simulation. In most scenarios, this will at least include a gravity force.