In this example, we will make a crease in a simple tube, since it is similar to a pant leg.
Create a Tube, change its Primitive Type to Polygon, and add increase the Rows and Columns to a reasonable level of details. In this example, the tube has and Height of
Select an edge for your crease.
With the edge selected, create a group by pressing ⇥ Tab in the viewport and typing Group Geometry.
Give the edge group a Group Name. For example,
Click the button two more times to create a total of three attributes.
Name the first attribute
shellstretchstiffness, with a Default of
1, and a Value of
3. Do the same thing for two more attributes:
shellweakbendstiffness. This will make the crease 3 times as stiff as the rest of the pant leg.
Use the Cloth Object shelf tool to turn the tube into a cloth object.
For this example we will simply pin the top of the tube so it does not fall by clicking the Follow Target shelf tool, and choosing the top loop of the tube to constrain.
In a real-life example you would be attaching the pants to the waist using the Attach to Body on the Cloth shelf tab and following the prompts. See How to create a simple cloth skirt and attach it to a character.
Add an Edit SOP before the DOP Import node and model the crease by selecting the edge again and transforming it out as far as you want it.
You can type your edge group name, for example
creasein the Group parameter to quickly select the edge to transform. Additionally, increasing the Soft Radius will make a more natural looking crease.
Press play on the Playbar to view the simulation. Your cloth should hang with a stiff crease.