Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 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 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 31x 31x 1x 1x 1x 1266x 1266x 1266x 162x 162x 162x 1104x 1104x 1x 1x 80x 80x 80x 80x 80x 140x 140x 80x 80x 1x 1x 11073x 11072x 11072x 7x 11072x 11065x 11065x 11072x 11072x 11072x 9551x 9551x 9551x 9551x 9551x 9551x 11073x 11073x 11073x 9551x 9551x 9551x 9551x 9551x 9551x 9551x 9551x 11073x 11073x 11073x 11073x 11073x 11073x 11073x 11073x 36598x 36598x 36598x 36598x 11073x 1x 1x 1x 1x 1x 1x 1x 11073x 1x 1x 24200x 24200x 86065x 86065x 23430x 23430x 1x 1x 14173x 14173x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 11559x 1x 1x 1x 1x 1x 11559x 11558x 11558x 11559x 14173x 1x 1x 11069x 11069x 364x 364x 364x 1328x 1328x 1328x 364x 364x 364x 364x 364x 364x 364x 364x 364x 11069x 1x 1x 11069x 11069x 541x 1827x 1827x 541x 11069x 1x 1x 3x 1x 1x 7x 1x 1x 3882x 1x | /*----------------------------------------------------------------------+
| Title: LineElement.ts |
| A port of the software Geometry Applet by |
| Author: David E. Joyce |
| Department of Mathematics and Computer Science |
| Clark University |
| Worcester, MA 01610-1477 |
| U.S.A. |
| |
| http://aleph0.clarku.edu/~djoyce/home.html |
| djoyce@clarku.edu |
| |
| Date: February, 1996. Version 2.0.0 May, 1997. |
| TypeScript Port: 2019, Nelson Brown, brownnrl@gmail.com |
| https://www.nelsonbrown.net/ |
+----------------------------------------------------------------------*/
import {PointElement} from "../point/PointElement";
import {GeomElement} from "../GeomElement";
import {SlateCanvas} from "../../Slate";
export class PolygonElement extends GeomElement {
public V : PointElement[];
// Face fill alpha — drives drawFace's globalAlpha independent of
// drawProgress (which drives the edge trace). Lets an animation
// run the outline to completion at drawProgress = 1 first, then
// separately fade the fill in by ticking faceAlpha 0 → 1. Default
// 1 means "fully opaque" — every existing render path behaves
// identically.
private _faceAlpha : number = 1;
set faceAlpha(value: number) {
this._faceAlpha = value < 0 ? 0 : (value > 1 ? 1 : value);
}
get faceAlpha(): number { return this._faceAlpha; }
constructor(ps?: PointElement[]) {
super();
this.dimension = 2;
if (ps == null) {
this.V = [];
return;
}
this.V = ps;
}
public area() : number {
// Ported from PolygonElement.java area() — 2026-04-12
// Compute the area of this polygon (assuming it's planar & convex).
// Uses fan triangulation from V[0].
let sum = 0.0;
for (let i = 0; i < this.V.length - 2; ++i) {
sum += PointElement.area(this.V[0], this.V[i + 1], this.V[i + 2]);
}
return sum;
}
public drawEdge(c: HTMLCanvasElement, color?: string): void {
if (!this.visible && !this.shouldHighlight && this.emphasisAmount <= 0) return;
if (color == null) {
if (this.emphasized || this.shouldHighlight) {
color = this.edgeHighlightColor;
} else {
color = this.edgeColor;
}
}
if (color == null) return;
if (this.V.length <= 1) return;
let ctx = c.getContext("2d");
ctx.beginPath();
ctx.strokeStyle = color;
{
const baseW = this.shouldHighlight ? 3 : 1;
ctx.lineWidth = (baseW + this.emphasisAmount * (6 - baseW)) * GeomElement.styleScale;
}
// Edge enumeration: a closed polygon (>2 verts) has V.length
// edges including the closing one; an open polyline has
// V.length - 1. Each integer step of drawProgress · edgeCount
// advances one full edge; the fractional remainder partially
// traces the next. drawProgress = 1 (default) reproduces the
// pre-animation full-trace behaviour bit-for-bit.
let n = this.V.length;
let isClosed = n > 2;
let edgeCount = isClosed ? n : n - 1;
let p = this.drawProgress;
let totalProgress = p * edgeCount;
let fullEdges = Math.floor(totalProgress);
let fractionalEdge = totalProgress - fullEdges;
ctx.moveTo(this.V[0].x, this.V[0].y);
for (let i = 0; i < fullEdges; i++) {
let to = this.V[(i + 1) % n];
ctx.lineTo(to.x, to.y);
ctx.stroke();
}
if (fractionalEdge > 0 && fullEdges < edgeCount) {
let from = this.V[fullEdges];
let to = this.V[(fullEdges + 1) % n];
let px = from.x + (to.x - from.x) * fractionalEdge;
let py = from.y + (to.y - from.y) * fractionalEdge;
ctx.lineTo(px, py);
ctx.stroke();
}
}
public defined() : boolean {
if (this.V.length == 0) return false;
for(let v of this.V) {
if (!v.defined()) return false;
}
return true;
}
public drawFace(c: SlateCanvas): void {
if (!this.visible && !this.shouldHighlight && this.emphasisAmount <= 0) return;
if(this.faceColor != null && this.defined() && this.V.length > 2) {
let ctx : CanvasRenderingContext2D = c.getContext("2d") as CanvasRenderingContext2D;
ctx.beginPath();
ctx.fillStyle = this.faceColor;
let firstPoint = this.V[0];
let rest = this.V.slice(1);
ctx.moveTo(firstPoint.x, firstPoint.y);
for(let vertex of rest)
ctx.lineTo(vertex.x, vertex.y);
ctx.closePath();
// Animate the fill via the dedicated faceAlpha field so
// outline-then-fill animations can run the edge trace to
// completion at drawProgress = 1 first, then independently
// tick faceAlpha from 0 to 1 for the fade-in. Default
// faceAlpha = 1 preserves the fully-opaque behaviour for
// every consumer that doesn't animate.
let a = this.faceAlpha;
if (a < 1) {
if (a <= 0) return; // fully transparent — skip
ctx.save();
ctx.globalAlpha = a;
ctx.fill();
ctx.restore();
} else {
ctx.fill();
}
}
}
public drawName(c: SlateCanvas): void {
if (!this.visible && !this.shouldHighlight && this.emphasisAmount <= 0) return;
if (this.nameColor != null && this.name != null && this.defined()) {
let x : number = 0;
let y : number = 0;
for(let v of this.V) {
x += v.x;
y += v.y;
}
let n : number = this.V.length;
x = x / n;
y = y / n;
let ctx : CanvasRenderingContext2D = c.getContext("2d") as CanvasRenderingContext2D;
let [w, h] = this._getTextMetrics(ctx, this._name);
ctx.beginPath();
ctx.fillStyle = this.nameColor;
ctx.fillText(this._name, x - w/2., y + h/4.);
}
}
public drawVertex(c: SlateCanvas): void {
if (!this.visible && !this.shouldHighlight && this.emphasisAmount <= 0) return;
if (this.vertexColor != null && this.defined() ) {
for(let v of this.V) {
v.drawVertex(c, this.vertexColor);
}
}
}
public rotate(pivot: PointElement, ac: number, as: number): void {
}
public translate(dx: number, dy: number): void {
}
public update(): void {
}
}
|