playcanvas/build/playcanvas/src/core/shape/frustum.js

Open-source WebGL/WebGPU 3D engine for the web

import { Plane } from "./plane.js";
class Frustum {
	planes = [];
	constructor() {
		for (let i = 0; i < 6; i++) {
			this.planes[i] = new Plane();
		}
	}
	clone() {
		const cstr = this.constructor;
		return new cstr().copy(this);
	}
	copy(src) {
		for (let i = 0; i < 6; i++) {
			this.planes[i].copy(src.planes[i]);
		}
		return this;
	}
	setFromMat4(matrix) {
		const d = matrix.data;
		const m00 = d[0], m01 = d[1], m02 = d[2], m03 = d[3];
		const m10 = d[4], m11 = d[5], m12 = d[6], m13 = d[7];
		const m20 = d[8], m21 = d[9], m22 = d[10], m23 = d[11];
		const m30 = d[12], m31 = d[13], m32 = d[14], m33 = d[15];
		const planes = this.planes;
		planes[0].set(m03 - m00, m13 - m10, m23 - m20, m33 - m30).normalize();
		planes[1].set(m03 + m00, m13 + m10, m23 + m20, m33 + m30).normalize();
		planes[2].set(m03 + m01, m13 + m11, m23 + m21, m33 + m31).normalize();
		planes[3].set(m03 - m01, m13 - m11, m23 - m21, m33 - m31).normalize();
		planes[4].set(m03 - m02, m13 - m12, m23 - m22, m33 - m32).normalize();
		planes[5].set(m03 + m02, m13 + m12, m23 + m22, m33 + m32).normalize();
	}
	containsPoint(point) {
		for (let p = 0; p < 6; p++) {
			const { normal, distance } = this.planes[p];
			if (normal.dot(point) + distance <= 0) {
				return false;
			}
		}
		return true;
	}
	add(other) {
		const planes = this.planes;
		const otherPlanes = other.planes;
		for (let p = 0; p < 6; p++) {
			if (otherPlanes[p].distance > planes[p].distance) {
				planes[p].copy(otherPlanes[p]);
			}
		}
		return this;
	}
	containsSphere(sphere) {
		const { center, radius } = sphere;
		let c = 0;
		for (let p = 0; p < 6; p++) {
			const { normal, distance } = this.planes[p];
			const d = normal.dot(center) + distance;
			if (d <= -radius) {
				return 0;
			}
			if (d > radius) {
				c++;
			}
		}
		return c === 6 ? 2 : 1;
	}
}
export {
	Frustum
};