Repository navigation
Expand file tree
/
Copy pathquadtree.js
More file actions
190 lines (167 loc) · 5.2 KB
/
Copy pathquadtree.js
File metadata and controls
190 lines (167 loc) · 5.2 KB
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
189
190
import "../core/functor";
import "../svg/line";
import "geom";
d3.geom.quadtree = function(points, x1, y1, x2, y2) {
var x = d3_svg_lineX,
y = d3_svg_lineY,
compat;
// For backwards-compatibility.
if (compat = arguments.length) {
x = d3_geom_quadtreeCompatX;
y = d3_geom_quadtreeCompatY;
if (compat === 3) {
y2 = y1;
x2 = x1;
y1 = x1 = 0;
}
return quadtree(points);
}
function quadtree(data) {
var d,
fx = d3_functor(x),
fy = d3_functor(y),
xs,
ys,
i,
n,
x1_,
y1_,
x2_,
y2_;
if (x1 != null) {
x1_ = x1, y1_ = y1, x2_ = x2, y2_ = y2;
} else {
// Compute bounds, and cache points temporarily.
x2_ = y2_ = -(x1_ = y1_ = Infinity);
xs = [], ys = [];
n = data.length;
if (compat) for (i = 0; i < n; ++i) {
d = data[i];
if (d.x < x1_) x1_ = d.x;
if (d.y < y1_) y1_ = d.y;
if (d.x > x2_) x2_ = d.x;
if (d.y > y2_) y2_ = d.y;
xs.push(d.x);
ys.push(d.y);
} else for (i = 0; i < n; ++i) {
var x_ = +fx(d = data[i], i),
y_ = +fy(d, i);
if (x_ < x1_) x1_ = x_;
if (y_ < y1_) y1_ = y_;
if (x_ > x2_) x2_ = x_;
if (y_ > y2_) y2_ = y_;
xs.push(x_);
ys.push(y_);
}
}
// Squarify the bounds.
var dx = x2_ - x1_,
dy = y2_ - y1_;
if (dx > dy) y2_ = y1_ + dx;
else x2_ = x1_ + dy;
// Recursively inserts the specified point p at the node n or one of its
// descendants. The bounds are defined by [x1, x2] and [y1, y2].
function insert(n, d, x, y, x1, y1, x2, y2) {
if (isNaN(x) || isNaN(y)) return; // ignore invalid points
if (n.leaf) {
var nx = n.x,
ny = n.y;
if (nx != null) {
// If the point at this leaf node is at the same position as the new
// point we are adding, we leave the point associated with the
// internal node while adding the new point to a child node. This
// avoids infinite recursion.
if ((Math.abs(nx - x) + Math.abs(ny - y)) < .01) {
insertChild(n, d, x, y, x1, y1, x2, y2);
} else {
var nPoint = n.point;
n.x = n.y = n.point = null;
insertChild(n, nPoint, nx, ny, x1, y1, x2, y2);
insertChild(n, d, x, y, x1, y1, x2, y2);
}
} else {
n.x = x, n.y = y, n.point = d;
}
} else {
insertChild(n, d, x, y, x1, y1, x2, y2);
}
}
// Recursively inserts the specified point [x, y] into a descendant of node
// n. The bounds are defined by [x1, x2] and [y1, y2].
function insertChild(n, d, x, y, x1, y1, x2, y2) {
// Compute the split point, and the quadrant in which to insert p.
var sx = (x1 + x2) * .5,
sy = (y1 + y2) * .5,
right = x >= sx,
bottom = y >= sy,
i = (bottom << 1) + right;
// Recursively insert into the child node.
n.leaf = false;
n = n.nodes[i] || (n.nodes[i] = d3_geom_quadtreeNode());
// Update the bounds as we recurse.
if (right) x1 = sx; else x2 = sx;
if (bottom) y1 = sy; else y2 = sy;
insert(n, d, x, y, x1, y1, x2, y2);
}
// Create the root node.
var root = d3_geom_quadtreeNode();
root.add = function(d) {
insert(root, d, +fx(d, ++i), +fy(d, i), x1_, y1_, x2_, y2_);
};
root.visit = function(f) {
d3_geom_quadtreeVisit(f, root, x1_, y1_, x2_, y2_);
};
// Insert all points.
i = -1;
if (x1 == null) {
while (++i < n) {
insert(root, data[i], xs[i], ys[i], x1_, y1_, x2_, y2_);
}
--i; // index of last insertion
} else data.forEach(root.add);
// Discard captured fields.
xs = ys = data = d = null;
return root;
}
quadtree.x = function(_) {
return arguments.length ? (x = _, quadtree) : x;
};
quadtree.y = function(_) {
return arguments.length ? (y = _, quadtree) : y;
};
quadtree.extent = function(_) {
if (!arguments.length) return x1 == null ? null : [[x1, y1], [x2, y2]];
if (_ == null) x1 = y1 = x2 = y2 = null;
else x1 = +_[0][0], y1 = +_[0][1], x2 = +_[1][0], y2 = +_[1][1];
return quadtree;
};
quadtree.size = function(_) {
if (!arguments.length) return x1 == null ? null : [x2 - x1, y2 - y1];
if (_ == null) x1 = y1 = x2 = y2 = null;
else x1 = y1 = 0, x2 = +_[0], y2 = +_[1];
return quadtree;
};
return quadtree;
};
function d3_geom_quadtreeCompatX(d) { return d.x; }
function d3_geom_quadtreeCompatY(d) { return d.y; }
function d3_geom_quadtreeNode() {
return {
leaf: true,
nodes: [],
point: null,
x: null,
y: null
};
}
function d3_geom_quadtreeVisit(f, node, x1, y1, x2, y2) {
if (!f(node, x1, y1, x2, y2)) {
var sx = (x1 + x2) * .5,
sy = (y1 + y2) * .5,
children = node.nodes;
if (children[0]) d3_geom_quadtreeVisit(f, children[0], x1, y1, sx, sy);
if (children[1]) d3_geom_quadtreeVisit(f, children[1], sx, y1, x2, sy);
if (children[2]) d3_geom_quadtreeVisit(f, children[2], x1, sy, sx, y2);
if (children[3]) d3_geom_quadtreeVisit(f, children[3], sx, sy, x2, y2);
}
}