File size: 1,609 Bytes
b82e8b8 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 |
function dot2D(vectorA, vectorB) { return vectorA[0] * vectorB[0] + vectorA[1] * vectorB[1]; }
function cross2D(vectorA, vectorB) { return vectorA[0] * vectorB[1] - vectorA[1] * vectorB[0]; }
function magnitude2D(vector) { return Math.sqrt(dot2D(vector, vector)); }
function perpendicular2D(v) { return [v[1], -v[0]]; }
function reverse2D(v) { return [-v[0], -v[1]]; }
function normalize2D(v) {
let length = Math.sqrt(dot2D(v, v));
if (length < 0.0001) { return [0.0, 0.0]; }
return [v[0] / length, v[1] / length];
}
function signedAngle(lhs, rhs) {return Math.atan2(cross2D(lhs, rhs), dot2D(lhs, rhs));}
function angleBetween(lhs, rhs) {return Math.abs(signedAngle(lhs, rhs));}
function positiveAngle(lhs, rhs) {
var a = signedAngle(lhs, rhs);
return a < 0 ? a + Math.PI * 2 : a;
}
function getSide(A, B, C, D) {
const BA = [A[0] - B[0], A[1] - B[1]];
const BD = [D[0] - B[0], D[1] - B[1]];
const BC = [C[0] - B[0], C[1] - B[1]];
const theta0 = positiveAngle(BA, BD);
const theta1 = positiveAngle(BA, BC);
if (theta0 == 0 || theta0 == theta1) {
return 0;
} else if (theta0 < theta1) {
return 1;
} else {
return -1
}
}
function slerp2D(ca, cb, t) {
const calen = magnitude2D(ca);
const cblen = magnitude2D(cb);
const lent = calen + (cblen - calen) * t;
const cq = [ca[0] * lent / calen, ca[1] * lent / calen];
const angle = signedAngle(ca, cb) * t;
const xt = cq[0] * Math.cos(angle) - cq[1] * Math.sin(angle);
const yt = cq[0] * Math.sin(angle) + cq[1] * Math.cos(angle);
return [xt, yt];
}
|