Last active
March 24, 2023 14:48
-
-
Save SharpCoder/c1fc69c71e903b132585561a4f4b15be to your computer and use it in GitHub Desktop.
Sphere/Cuboid Collision
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
function getAABB(rect: Cuboid) { | |
const result = { | |
min: [rect.x, rect.y, rect.z], | |
max: [rect.x + rect.w, rect.y + rect.h, rect.z + rect.d], | |
}; | |
// Swap the vertices if the min/max is reversed | |
// because of orientation or whatever. | |
for (let i = 0; i < 3; i++) { | |
if (result.max[i] < result.min[i]) { | |
// Swap | |
const a = result.min[i]; | |
result.min[i] = result.max[i]; | |
result.max[i] = a; | |
} | |
} | |
return result; | |
} | |
function squaredDistPointAABB(sphere: Sphere, rect: Cuboid) { | |
let sqDist = 0; | |
const p = [sphere.x, sphere.y, sphere.z]; | |
const b = getAABB(rect); | |
for (let i = 0; i < 3; i++) { | |
// for each axis count any excess distance outside box extents | |
let v = p[i]; | |
if (v < b.min[i]) sqDist += (b.min[i] - v) * (b.min[i] - v); | |
if (v > b.max[i]) sqDist += (v - b.max[i]) * (v - b.max[i]); | |
} | |
return sqDist; | |
} | |
export function sphereRectCollision( | |
sphere: Sphere, | |
rect: Cuboid | |
): [boolean, number] { | |
// Compute squared distance between sphere center and AABB | |
// the sqrt(dist) is fine to use as well, but this is faster. | |
let sqDist = squaredDistPointAABB(sphere, rect); | |
// Sphere and AABB intersect if the (squared) distance between them is | |
// less than the (squared) sphere radius. | |
return [sqDist <= sphere.radius * sphere.radius, sqDist]; | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment