Compute Bounds Overlaps

Computes overlaps between pairs of axis aligned bounding boxes (broadphase)

Compute Bounds Overlaps Node

Compute Bounds Overlap is an Immediate Node that takes a set of Axis Aligned Bounding Boxes (AABB s) and can quickly find pairs of them that intersect each other.

This node can be used as a fast filter to avoid doing unnecessary and more expensive intersection tests, like for example the ones done by:

The input Prims Bundle can be an arbitrary number of child prim bundles with bounding box min and max attributes.

Installation

To use this Node, you must enable omni.physx.graph in the Extension Manager.

Inputs

Name

Type

Description

Default

execIn

execution

Input execution

primsBundle

bundle

The prims of interest. It must be a bundle with one or more prim children. Connect with ‘Compute Bounding Boxes’ or with ‘Read Prims’ checking ‘Compute bounding box’. For each child prim reads the: - ‘sourcePrimPath’ - ‘bboxMinCorner’ - ‘bboxMaxCorner’ (and optionally ‘bboxTransform’ and ‘worldMatrix’) attributes.

Outputs

Name

Type

Description

Default

execOut

execution

Output execution

overlapsPair0

token[]

Array of tokens where the one at a given index is the first body in an identified overlap pair (the second is at corresponding index in ‘overlapsPair1’ output).

overlapsPair1

token[]

Array of tokens where the one at a given index is the second body in an identified overlap pair (the first is at corresponding index in ‘overlapsPair0’ output).

Note

Input Prims Bundle can be obtained for example using the Read Prims node and flagging the Compute bounding box boolean option to True.

As an alternative, input Prims Bundle can more efficiently obtained by using the Read Prims node, with Compute bounding box option set to False and chain its bundle output to a Compute Geometry Bounds node, that will add the required bboxMinCorner and bboxMaxCorner attributes.

Important

Immediate nodes currently only support Mesh Prims, and not Shape prims.

Demos:

Several demo scenes can be accessed through the physics demo scenes menu option (Window > Simulation > Physics / Demo Scenes).

This will enable a Physics Demo Scenes window.

../../../../_images/kit_physics_demo_scenes.png

A demo using this node is labeled Objects de-penetration:

../../../../_images/omnigraph-physx-immediate-demo-de-penetration.png