Optimizing Physics Performance

The NVIDIA PhysX physics engine used by Unity is available on iOS but the performance limits of the hardware will be reached more easily on mobile platforms than desktops.

Here are some tips for tuning physics to get better performance on iOS:-

• You can adjust the Fixed Timestep setting (in the Time manager) to reduce the time spent on physics updates. Increasing the timestep will reduce the CPU overhead at the expense of the accuracy of the physics. Often, lower accuracy is an acceptable tradeoff for increased speed.
• Set the Maximum Allowed Timestep in the Time manager in the 8–10fps range to cap the time spent on physics in the worst case scenario.
• Los Mesh colliders tienen una mayor sobrecarga de rendimiento que los colliders primitivos, por lo que utilícelos escasamente. A menudo es posible aproximar la figura de un mesh al utilizar objetos hijos con colliders primitivos. Los colliders hijos serán controlados colectivamente como un solo collider compuesto por el rigidbody en el padre.
• Mientras que los wheel colliders (colliders de rueda) no son estrictamente unos colliders en el sentido de objetos sólidos, estos no obstante tienen una mayor carga de CPU.

The total amount of physics calculation depends on the number of non-sleeping rigid bodies and colliders in the scene and the complexity of the colliders. You can keep track of how many physics objects there are in the scene using the internal profiler.