line.js
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/**
* 线段包含判断
* @param {number} x0
* @param {number} y0
* @param {number} x1
* @param {number} y1
* @param {number} lineWidth
* @param {number} x
* @param {number} y
* @return {boolean}
*/
export function containStroke(x0, y0, x1, y1, lineWidth, x, y) {
if (lineWidth === 0) {
return false;
}
var _l = lineWidth;
var _a = 0;
var _b = x0;
// Quick reject
if (
(y > y0 + _l && y > y1 + _l)
|| (y < y0 - _l && y < y1 - _l)
|| (x > x0 + _l && x > x1 + _l)
|| (x < x0 - _l && x < x1 - _l)
) {
return false;
}
if (x0 !== x1) {
_a = (y0 - y1) / (x0 - x1);
_b = (x0 * y1 - x1 * y0) / (x0 - x1);
}
else {
return Math.abs(x - x0) <= _l / 2;
}
var tmp = _a * x - y + _b;
var _s = tmp * tmp / (_a * _a + 1);
return _s <= _l / 2 * _l / 2;
}