55 lines
1.7 KiB
JavaScript
55 lines
1.7 KiB
JavaScript
import GeometryPoint from "./GeometryPoint.js";
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import GeometryStroke from "./GeometryStroke.js";
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export default class GeometryLine
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{
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constructor(pointA, pointB)
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{
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this.pointA = pointA;
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this.pointB = pointB;
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}
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getIntersectionWithLine(line)
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{
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try {
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let xa = (line.pointB.x - line.pointA.x) * (this.pointB.x * this.pointA.y - this.pointA.x * this.pointB.y);
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let xb = (this.pointB.x - this.pointA.x) * (line.pointB.x * line.pointA.y - line.pointA.x * line.pointB.y);
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let xc = (line.pointB.y - line.pointA.y) * (this.pointB.x - this.pointA.x);
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let xd = (this.pointB.y - this.pointA.y) * (line.pointB.x - line.pointA.x);
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let x = (xa - xb) / (xc - xd);
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if (isNaN(x)) {
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return null;
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}
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let ya = (this.pointA.y - this.pointB.y) *(line.pointB.x * line.pointA.y - line.pointA.x * line.pointB.y);
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let yb = (line.pointA.y - line.pointB.y) *(this.pointB.x * this.pointA.y - this.pointA.x * this.pointB.y);
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let yc = (line.pointB.y - line.pointA.y) * (this.pointB.x - this.pointA.x);
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let yd = (this.pointB.y - this.pointA.y) * (line.pointB.x - line.pointA.x);
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let y = (ya - yb) / (yc - yd);
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if (isNaN(y)) {
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return null;
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}
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return new GeometryPoint(x, y);
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} catch (error) {
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return null;
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}
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}
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getStroke()
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{
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return new GeometryStroke(this.pointA, this.pointB);
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}
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draw(context)
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{
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context.beginPath();
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context.moveTo(this.pointA.x, this.pointA.y);
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context.lineTo(this.pointB.x, this.pointB.y);
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context.stroke();
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}
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} |