Unity3D: Intro to the Physics System
Here’s a short introduction to Unity's physics system and its components.
Physics in Unity enables objects to be controlled by the forces of gravity, velocity, and acceleration through simulation.
Rigidbody
The Rigidbody component allows a game object to be affected by physics and its forces in Unity.
Objects of larger mass are less affected by objects of lower mass and vice versa. “Drag” (air resistance) affects the dampening of velocity over time, and “Angular Drag” affects angular velocity. “Use Gravity” enabled will give the game object gravity.
“Is Kinematic” checked will affect other objects but will not affect themselves.
The Interpolate setting checks to see how collisions are registered.
- Interpolate: Smooth movements of objects are based on the information of the previous frame in an animation timeline.
- Extrapolate: Smooth movements of objects are based on a guess of the next frame.
The Collision Detection sets the rate at which collisions are checked.
- Discrete: Default.
- Continous: Fast objects that interact with static objects.
- Continous Dynamic: Fast objects that interact with other fast objects.
- Continuous Speculative: Predictive collision checking.
The Constraints define which axis objects should not move.
We can also redefine and change the different settings of the physics system of Unity by selecting the drop-down menu: Edit > Project Settings > Physics.
Colliders and Collisions
Colliders enable Unity to detect when game objects strike or intersect with each other.
A game object must have a Rigidbody component attached to them for collisions to happen.
Triggers
Triggers work the same as colliders but disable the physics of the component. It enables objects to “pass-through” a game object with the “Is Trigger” checked. You can call events when game objects enter or exit the Trigger.
One of the game objects MUST HAVE a Rigidbody component attached for interaction to occur between objects.
I would check out Unity’s documentation and explore other features about the Physic system Unity offers since there’s is a plethora of information on this subject alone!
