Why is my cloth simulation jagged? My cloth simulation sometimes works fine, but other times it does this.




This usually happens when the character jerks on to the cape suddenly. 

The top of the cape dose have a vertex group with 100% power, pinning it to the character, and the rest of the cape has only 10% power so it stays near him.

If you know how to stop the cloth simulation from going jagged at points then please let me know.
Try increasing the number of Steps under the cloth's Quality setting. Don't be afraid to increase it 3 or 4-fold: the simulation time will just increase proportionally (it will take 3 or 4 times longer to simulate), not exponentially (like with sub-surface steps).

When you increase the Steps count to - say - 15, each frame is split by the simulation engine in 15 sub-frames for calculation purposes. This is very useful when the collision/pinning objects have sudden accelerations, because it allows for the engine to deal with them in a finer way, in this case one fifteenth at a time.

Here's a comparison between a Quality = 2 steps and a Quality = 30 steps simulation. As you can see, the sudden accelerations create persistent and unrealistic wrinkles in the low-quality cape, while the high-quality one effectively and rapidly smooths them out (please note: my cape only has the 100% pinning on the top edge, and not the additional 10% one).



Additionally, you may want to increase the Quality value in the Cloth collision panel, but this isn't as relevant as the cloth quality.