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# nCloth Collision Properties Explained

Updated: Jun 9, 2020

Mayaâ€™s cloth simulation, nCloth, has a lot of attributes that users can fine tune to get the perfect simulation. For many people starting to use nCloth, it can be quite overwhelming. But fear not! Below you can see examples of each nCloth Collision Property attribute with a brief description of each. Letâ€™s dive in.

## Collision Properties

Enable

This one is straight forward. Enables or disables the nCloth calculation. If you have multiple nCloth objects in a scene and only need to simulate one at a particular moment you can disable the others. That way Maya will calculate less things and your scene will run faster.

Collide

Allow the cloth object to collide with other objects.

Self Collide

Allow the cloth objects to collide with itself. The self collision flag really come to play here.

Collision Flag

Determines which component mode the collision thickness will be applied to. This is how the object will calculate its collision with other objects. Options are:

Vertex: Collision spheres form around each vertex.

Edge: Collision cylinders form around each edge.

Face: Thickness greater than 0 calculates faces as the sum of faces, vertices, and edges. Therefore, The entire surface will have thickness. Important to note, the edges get round off.

Vertex Edge Face

*You can see this when you turn on the solver display

Self Collision Flag

Determines which component mode the self collisions will be based on. This is how the object will calculate its collision with itself. Options are:

Vertex: Spheres at the vertices, which means that the object will ignore when two edges and faces are close. It will only calculate when another vertex is getting close to each other.

VertexEdge: Both vertices and edges are being calculated when self-collision is at play.

VertexFace: Both vertices and faces are being calculated when self-collision is at play. The corners round off.

FullSurface: Sum of everything. You get spheres at the vertices, cylinders at the edges, and the offset of faces. The corners also round out here.

*In the viewport they look just like the 3 examples above.

Collision Strength

1 means the cloth will 100% recognize a collider. 0 means it wonâ€™t Recognize a collider as existing. Sometimes we have a cloth simulating on a character and thereâ€™s a piece of the cloth that we donâ€™t want it to collide with the character because it causes a strange deformation. Typically this occurs with hands or fingers on a character. This setting can be painted on an nCloth object or an nRigid object

Collision Layer

Useful when layering dynamic objects. This is your way of telling Maya calculate my body collider then pants and then my t-shirt. This way you have a better chance at avoiding penetrations. In this scenario, the body collider will be 0, the pants 1, and the shirt 2. You want to set up the numbers according to what object is pushing another object out. The lowest number has the higher push out priority.

Thickness

This is how thick you want the collision to be. Think of this as the thickness of the object.

Self Collide Width Scale

This is he thickness between the components. If you set the self collide flag to vertex or edge, you can see this best. It is like having a force field around that component and other nearby components canâ€™t go inside it.

Solver Display

There are various options here. This allows you to physically see a yellow shape representing the thickness of each of the categories in the list. The list consist of:

Off: Turns off the display

Collision Thickness: Visual representation of the thickness based on the collision flag you set.

Self Collision Thickness: Visual representation of the self collide width scale based on the self collision flag you set.

Bend Links: This is how nCloth calculates how each face can bend during simulation

Weighting: Show which vertex is calculated first based on the vertex size. Only visible if Stretch Links is turned on in the quality settings.

Display Color

Allows you to change the color of the silver display. Default is yellow.

Bounce

The amount of bounce a cloth has. This is how much rebound it will have during impact with itself or other objects. *Use with caution. Values greater than 1 cause instability. Cloth isn't suppose to be bouncy, so if you want to do something like a deflated basket ball you will also need to increase bend resistance, deform resistance, and possibly rigidity to get the full affect of what you are looking for.

Friction

Just like science class, friction has to do with a resistance to motion against other objects. 0 will move smoothly across things like silk, whereas a friction of one will be rough like burlap. This attribute is an additive to the the stickiness attribute of the cloth object as well as any stickiness on anything it is colliding with.

Stickiness

Literally what the name describes. How much an object sticks to another. Because friction and stickiness are additive, for a fully self sticky cloth affect turn both stickiness and friction to 1. If you set both stickiness and friction to 2, other objects that have 0 stickiness will stick to it.

There you have it! All of the main collision properties of nCloth. Open up Maya and play around with these settings. Get familiar with each and make sure to read the other nCloth properties posts to really be able to dive into your understanding of nCloth.

As always we love to hear from you. Leave comments or message us! Subscribe to our page to get more information about our blog! We will soon post more articles about the other nCloth properties.

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