PhysX is a physics engine running on CPU or GPU. Only Nvidia hardware is designed for PhysX usage. GPU usage typically provides better gaming performance
Original physics engine was considered realistic but had numerous failures. Spring physics was first used, running at 4000 Hz before being deprecated. Spring physics allowed parts to bend but was unreliable with hinges
Colliders enable physics engine to handle collisions between objects. Triggers are special collider setups that trigger events when objects overlap. Most objects come with colliders, custom meshes require additional components
PhysX started as NovodeX physics engine by ETH Zurich spin-off. Ageia acquired NovodeX AG in 2004 and developed PhysX technology. First game using PhysX was The Stalin Subway in 2005
GameObjects are fundamental building blocks for 2D games. Transform component controls position, rotation, and scale of GameObjects. Sprite Renderer displays images as 2D graphics. Collider 2D defines shape for physical collisions
Rigid body simulation allows objects to fall, collide without deformation. Blender uses Bullet physics system for rigid body simulations. Objects can be active (force-acting) or passive (floating)