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line.js
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line.js
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class Line {
constructor(start, end) {
this.start = start;
this.end = end;
}
draw() {
stroke(255);
strokeWeight(2);
line(this.start.x, this.start.y, this.end.x, this.end.y);
}
static getRandomLines(numLines) {
let lines = [];
for (let i = 0; i < numLines; i++) {
let start = createVector(random(width), random(height));
let end = createVector(random(width), random(height));
lines.push(new Line(start, end));
}
lines.push(new Line(createVector(0, 0), createVector(width, 0)));
lines.push(new Line(createVector(0, 0), createVector(0, height)));
lines.push(new Line(createVector(width, 0), createVector(width, height)));
lines.push(new Line(createVector(0, height), createVector(width, height)));
return lines;
}
static castRay(from, to) {
let ray = new Line(from, to);
return ray;
}
getIntersection(others) {
let nearestPoint = null;
let minT1 = Infinity;
for (let other of others) {
let point = this.checkIntersection(other);
if (point && point.t < minT1) {
minT1 = point.t;
nearestPoint = point.xy;
}
}
return nearestPoint;
}
checkIntersection(other) {
let r_px = this.start.x;
let r_py = this.start.y;
let r_dx = this.end.x - this.start.x;
let r_dy = this.end.y - this.start.y;
let s_px = other.start.x;
let s_py = other.start.y;
let s_dx = other.end.x - other.start.x;
let s_dy = other.end.y - other.start.y;
let T2 = (r_dx * (s_py - r_py) + r_dy * (r_px - s_px)) / (s_dx * r_dy - s_dy * r_dx)
let T1 = (s_px + s_dx * T2 - r_px) / r_dx
if (T1 > 0 && 0 < T2 && T2 < 1) {
let x = r_px + r_dx * T1;
let y = r_py + r_dy * T1;
return { t: T1, xy: createVector(x, y) };
}
return;
}
}