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fcf3b03 | 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 | import "../core/functor";
import "../math/abs";
import "geom";
import "point";
d3.geom.quadtree = function(points, x1, y1, x2, y2) {
var x = d3_geom_pointX,
y = d3_geom_pointY,
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 ((abs(nx - x) + abs(ny - y)) < 0.01) {
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 xm = (x1 + x2) * 0.5,
ym = (y1 + y2) * 0.5,
right = x >= xm,
below = y >= ym,
i = below << 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 = xm; else x2 = xm;
if (below) y1 = ym; else y2 = ym;
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_);
};
// Find the closest point to the specified point.
// TODO allow the initial search extent to be specified?
// TODO allow the initial minimum distance to be specified?
// TODO allow searching below any node?
root.find = function(point) {
return d3_geom_quadtreeFind(root, point[0], point[1], 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) * 0.5,
sy = (y1 + y2) * 0.5,
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);
}
}
function d3_geom_quadtreeFind(root, x, y, x0, y0, x3, y3) {
var minDistance2 = Infinity,
closestPoint;
(function find(node, x1, y1, x2, y2) {
// stop searching if this cell can’t contain a closer node
if (x1 > x3 || y1 > y3 || x2 < x0 || y2 < y0) return;
// visit this point
if (point = node.point) {
var point,
dx = x - node.x,
dy = y - node.y,
distance2 = dx * dx + dy * dy;
if (distance2 < minDistance2) {
var distance = Math.sqrt(minDistance2 = distance2);
x0 = x - distance, y0 = y - distance;
x3 = x + distance, y3 = y + distance;
closestPoint = point;
}
}
// bisect the current node
var children = node.nodes,
xm = (x1 + x2) * 0.5,
ym = (y1 + y2) * 0.5,
right = x >= xm,
below = y >= ym;
// visit closest cell first
for (var i = below << 1 | right, j = i + 4; i < j; ++i) {
if (node = children[i & 3]) switch (i & 3) {
case 0: find(node, x1, y1, xm, ym); break;
case 1: find(node, xm, y1, x2, ym); break;
case 2: find(node, x1, ym, xm, y2); break;
case 3: find(node, xm, ym, x2, y2); break;
}
}
})(root, x0, y0, x3, y3);
return closestPoint;
}
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