| export default function(a, b, x0, y0, x1, y1) { |
| var ax = a[0], |
| ay = a[1], |
| bx = b[0], |
| by = b[1], |
| t0 = 0, |
| t1 = 1, |
| dx = bx - ax, |
| dy = by - ay, |
| r; |
|
|
| r = x0 - ax; |
| if (!dx && r > 0) return; |
| r /= dx; |
| if (dx < 0) { |
| if (r < t0) return; |
| if (r < t1) t1 = r; |
| } else if (dx > 0) { |
| if (r > t1) return; |
| if (r > t0) t0 = r; |
| } |
|
|
| r = x1 - ax; |
| if (!dx && r < 0) return; |
| r /= dx; |
| if (dx < 0) { |
| if (r > t1) return; |
| if (r > t0) t0 = r; |
| } else if (dx > 0) { |
| if (r < t0) return; |
| if (r < t1) t1 = r; |
| } |
|
|
| r = y0 - ay; |
| if (!dy && r > 0) return; |
| r /= dy; |
| if (dy < 0) { |
| if (r < t0) return; |
| if (r < t1) t1 = r; |
| } else if (dy > 0) { |
| if (r > t1) return; |
| if (r > t0) t0 = r; |
| } |
|
|
| r = y1 - ay; |
| if (!dy && r < 0) return; |
| r /= dy; |
| if (dy < 0) { |
| if (r > t1) return; |
| if (r > t0) t0 = r; |
| } else if (dy > 0) { |
| if (r < t0) return; |
| if (r < t1) t1 = r; |
| } |
|
|
| if (t0 > 0) a[0] = ax + t0 * dx, a[1] = ay + t0 * dy; |
| if (t1 < 1) b[0] = ax + t1 * dx, b[1] = ay + t1 * dy; |
| return true; |
| } |
|
|
