playcanvas
Version:
Open-source WebGL/WebGPU 3D engine for the web
102 lines (101 loc) • 2.83 kB
JavaScript
import { Plane } from "./plane.js";
import { Vec3 } from "../math/vec3.js";
const _c23 = new Vec3();
const _c31 = new Vec3();
const _c12 = new Vec3();
const _corner = new Vec3();
function intersectPlanes(p1, p2, p3, out) {
_c23.cross(p2.normal, p3.normal);
const denom = p1.normal.dot(_c23);
if (Math.abs(denom) < 1e-6) {
return false;
}
_c31.cross(p3.normal, p1.normal);
_c12.cross(p1.normal, p2.normal);
const invDenom = -1 / denom;
out.set(
(p1.distance * _c23.x + p2.distance * _c31.x + p3.distance * _c12.x) * invDenom,
(p1.distance * _c23.y + p2.distance * _c31.y + p3.distance * _c12.y) * invDenom,
(p1.distance * _c23.z + p2.distance * _c31.z + p3.distance * _c12.z) * invDenom
);
return isFinite(out.x) && isFinite(out.y) && isFinite(out.z);
}
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 op = other.planes;
for (let zi = 4; zi <= 5; zi++) {
for (let xi = 0; xi <= 1; xi++) {
for (let yi = 2; yi <= 3; yi++) {
if (intersectPlanes(op[zi], op[xi], op[yi], _corner)) {
for (let p = 0; p < 6; p++) {
const plane = planes[p];
const d = plane.normal.dot(_corner) + plane.distance;
if (d < 0) {
plane.distance -= d;
}
}
}
}
}
}
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
};