114 lines
2.7 KiB
JavaScript
114 lines
2.7 KiB
JavaScript
/** Copyright Stewart Allen <sa@grid.space> -- All Rights Reserved */
|
|
|
|
"use strict";
|
|
|
|
// dep: geo.base
|
|
// use: geo.line
|
|
// use: geo.point
|
|
gapp.register("geo.slope", [], (root, exports) => {
|
|
|
|
const { base } = root;
|
|
const { config } = base;
|
|
|
|
const ABS = Math.abs,
|
|
DEG2RAD = Math.PI / 180,
|
|
RAD2DEG = 180 / Math.PI;
|
|
|
|
class Slope {
|
|
constructor(p1, p2, dx, dy) {
|
|
this.dx = p1 && p2 ? p2.x - p1.x : dx;
|
|
this.dy = p1 && p2 ? p2.y - p1.y : dy;
|
|
this.angle = Math.atan2(this.dy, this.dx) * RAD2DEG;
|
|
}
|
|
|
|
toString() {
|
|
return [this.dx, this.dy, this.angle].join(',');
|
|
}
|
|
|
|
clone() {
|
|
return new Slope(null, null, this.dx, this.dy);
|
|
}
|
|
|
|
isSame(s) {
|
|
// if very close to vertical or horizontal, they're the same
|
|
if (ABS(this.dx) <= config.precision_merge && ABS(s.dx) <= config.precision_merge) return true;
|
|
if (ABS(this.dy) <= config.precision_merge && ABS(s.dy) <= config.precision_merge) return true;
|
|
// check angle within a range
|
|
let prec = Math.min(1/Math.sqrt(this.dx * this.dx + this.dy * this.dy), config.precision_slope_merge);
|
|
return angleWithinDelta(this.angle, s.angle, prec || config.precision_slope);
|
|
}
|
|
|
|
normal() {
|
|
let t = this.dx;
|
|
this.dx = -this.dy;
|
|
this.dy = t;
|
|
this.angle = Math.atan2(this.dy, this.dx) * RAD2DEG;
|
|
return this;
|
|
}
|
|
|
|
invert() {
|
|
this.dx = -this.dx;
|
|
this.dy = -this.dy;
|
|
this.angle = Math.atan2(this.dy, this.dx) * RAD2DEG;
|
|
return this;
|
|
}
|
|
|
|
toUnit() {
|
|
let max = Math.max(ABS(this.dx), ABS(this.dy));
|
|
this.dx = this.dx / max;
|
|
this.dy = this.dy / max;
|
|
return this;
|
|
}
|
|
|
|
factor(f) {
|
|
this.dx *= f;
|
|
this.dy *= f;
|
|
return this;
|
|
}
|
|
|
|
invert() {
|
|
this.dx = -this.dx;
|
|
this.dy = -this.dy;
|
|
this.angle = 180 - this.angle;
|
|
return this;
|
|
}
|
|
|
|
angleDiff(s2,sign) {
|
|
const n1 = this.angle;
|
|
const n2 = s2.angle;
|
|
let diff = n2 - n1;
|
|
while (diff < -180) diff += 360;
|
|
while (diff > 180) diff -= 360;
|
|
return sign ? diff : Math.abs(diff);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* returns true if the difference between a & b is less than v
|
|
*/
|
|
function minDeltaABS(a,b,v) {
|
|
return ABS(a-b) < v;
|
|
}
|
|
|
|
function angleWithinDelta(a1, a2, delta) {
|
|
return (ABS(a1-a2) <= delta || 360-ABS(a1-a2) <= delta);
|
|
}
|
|
|
|
function newSlope(p1, p2, dx, dy) {
|
|
return new Slope(p1, p2, dx, dy);
|
|
}
|
|
|
|
function newSlopeFromAngle(angle) {
|
|
return newSlope(0,0,
|
|
Math.cos(angle * DEG2RAD),
|
|
Math.sin(angle * DEG2RAD)
|
|
);
|
|
}
|
|
|
|
gapp.overlay(base, {
|
|
Slope,
|
|
newSlope,
|
|
newSlopeFromAngle
|
|
});
|
|
|
|
});
|