Contents
Why do we need collision detection in rigid bodies?
Because we represent a rigid body as a set of particles, collision detection between rigid bodies with complicated shapes means we simply need to detect collisions between particles. When the distance between two particles is smaller than their diameter, collision occurs.
How to compute collision in GPU collision detection?
There are several ways to compute collision. In this subsection, we describe a method that is well suited to GPUs and real-time simulation. In our method, collision detection is based not on the polygons that represent the rigid bodies, but on particles, as done by Bell et al. (2005) and Tanaka et al. (2006).
Can a GPU be used for rigid body simulation?
Section 29.1 outlines our approach and Section 29.2 provides a detailed description of its implementation on the GPU. Several studies use GPUs to accelerate physically based simulations, such as cellular automata (Owens et al. 2005), Eulerian fluid dynamics (Harris 2004), and cloth simulation (Zeller 2005).
How is the motion of a rigid body computed?
The motion of a rigid body is computed by dividing motion into two parts:—translation and rotation—as shown in Figure 29-2. Translation describes the motion of the center of mass, whereas rotation describes how the rigid body rotates around the center of mass.
What are the purpose of collision tests in PhysX?
They are used for three purposes within PhysX: intersection tests that determine the contacting features of rigid objects, scene query tests such as raycasts, and defining trigger volumes that generate notifications when other shapes intersect with them. Shapes are reference counted, see Reference Counting.
When to use pxbroadphasetype for rigid body collision?
PxBroadPhaseType::eSAP is a good generic choice with great performance when many objects are sleeping. Performance can degrade significantly though, when all objects are moving, or when large numbers of objects are added to or removed from the broad-phase. This algorithm does not need world bounds to be defined in order to work.
How is the collision component treated as a trigger volume?
If the entity also has a rigidbody component, the collision component determines the shape of the rigid body. If no rigidbody component is present, the collision component is treated as a trigger volume. The trigger volume cannot affect the simulation of other rigid bodies in the scene.