parry3d::query::details

Function intersection_test

Source 
pub fn intersection_test(
    pos1: &Isometry<f32>,
    g1: &dyn Shape,
    pos2: &Isometry<f32>,
    g2: &dyn Shape,
) -> Result<bool, Unsupported>
Expand description

Tests whether two shapes are intersecting (overlapping).

This is the fastest collision query, returning only a boolean result without computing contact points, normals, or penetration depth. Use this when you only need to know if shapes collide, not where or how much.

§Behavior

Returns true if:

  • Shapes are touching (surfaces just make contact)
  • Shapes are penetrating (overlapping with any amount)

Returns false if:

  • Shapes are separated (any distance apart, even very close)

§Performance

This is the fastest collision detection query:

  • Ball-Ball: Extremely fast (just distance check)
  • AABB-AABB: Very fast (6 comparisons in 3D)
  • Convex-Convex: Fast (early-exit GJK algorithm)
  • Concave shapes: Uses BVH for acceleration

Significantly faster than contact() or distance() because it can terminate early once any intersection is found.

§Arguments

  • pos1 - Position and orientation of the first shape
  • g1 - The first shape
  • pos2 - Position and orientation of the second shape
  • g2 - The second shape

§Returns

  • Ok(true) - Shapes are intersecting
  • Ok(false) - Shapes are not intersecting
  • Err(Unsupported) - This shape pair combination is not supported

§Example

use parry3d::query::intersection_test;
use parry3d::shape::Ball;
use nalgebra::Isometry3;

let ball1 = Ball::new(1.0);
let ball2 = Ball::new(1.0);

// Overlapping balls
let pos1 = Isometry3::translation(0.0, 0.0, 0.0);
let pos2 = Isometry3::translation(1.5, 0.0, 0.0);

let intersecting = intersection_test(&pos1, &ball1, &pos2, &ball2).unwrap();
assert!(intersecting); // Distance 1.5 < combined radii 2.0

// Separated balls
let pos3 = Isometry3::translation(5.0, 0.0, 0.0);
let not_intersecting = intersection_test(&pos1, &ball1, &pos3, &ball2).unwrap();
assert!(!not_intersecting); // Distance 5.0 > combined radii 2.0

§Use Cases

  • Trigger volumes: Detect when player enters an area
  • Broad-phase: Quickly filter out distant object pairs
  • Game logic: Simple overlap detection (pickup items, damage zones)
  • Optimization: Pre-check before expensive narrow-phase queries

§When to Use Other Queries

§See Also