-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathcircle.js
More file actions
146 lines (120 loc) · 3.87 KB
/
Copy pathcircle.js
File metadata and controls
146 lines (120 loc) · 3.87 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
// TODO breakAtDateLine?
d3.geo.circle = function() {
var origin = [0, 0],
degrees = 90 - 1e-2,
radians = degrees * d3_geo_radians,
arc = d3.geo.greatArc().target(Object);
function circle() {
// TODO render a circle as a Polygon
}
function visible(point) {
return arc.distance(point) < radians;
}
circle.clip = function(d) {
arc.source(typeof origin === "function" ? origin.apply(this, arguments) : origin);
return clipType(d);
};
var clipType = d3_geo_type({
FeatureCollection: function(o) {
var features = o.features.map(clipType).filter(Object);
return features && (o = Object.create(o), o.features = features, o);
},
Feature: function(o) {
var geometry = clipType(o.geometry);
return geometry && (o = Object.create(o), o.geometry = geometry, o);
},
Point: function(o) {
return visible(o.coordinates) && o;
},
MultiPoint: function(o) {
var coordinates = o.coordinates.filter(visible);
return coordinates.length && {
type: o.type,
coordinates: coordinates
};
},
LineString: function(o) {
var coordinates = clip(o.coordinates);
return coordinates.length && (o = Object.create(o), o.coordinates = coordinates, o);
},
MultiLineString: function(o) {
var coordinates = o.coordinates.map(clip).filter(function(d) { return d.length; });
return coordinates.length && (o = Object.create(o), o.coordinates = coordinates, o);
},
Polygon: function(o) {
var coordinates = o.coordinates.map(clip);
return coordinates[0].length && (o = Object.create(o), o.coordinates = coordinates, o);
},
MultiPolygon: function(o) {
var coordinates = o.coordinates.map(function(d) { return d.map(clip); }).filter(function(d) { return d[0].length; });
return coordinates.length && (o = Object.create(o), o.coordinates = coordinates, o);
},
GeometryCollection: function(o) {
var geometries = o.geometries.map(clipType).filter(Object);
return geometries.length && (o = Object.create(o), o.geometries = geometries, o);
}
});
function clip(coordinates) {
var i = -1,
n = coordinates.length,
clipped = [],
p0,
p1,
p2,
d0,
d1;
while (++i < n) {
d1 = arc.distance(p2 = coordinates[i]);
if (d1 < radians) {
if (p1) clipped.push(d3_geo_greatArcInterpolate(p1, p2)((d0 - radians) / (d0 - d1)));
clipped.push(p2);
p0 = p1 = null;
} else {
p1 = p2;
if (!p0 && clipped.length) {
clipped.push(d3_geo_greatArcInterpolate(clipped[clipped.length - 1], p1)((radians - d0) / (d1 - d0)));
p0 = p1;
}
}
d0 = d1;
}
if (p1 && clipped.length) {
d1 = arc.distance(p2 = clipped[0]);
clipped.push(d3_geo_greatArcInterpolate(p1, p2)((d0 - radians) / (d0 - d1)));
}
return resample(clipped);
}
// Resample coordinates, creating great arcs between each.
function resample(coordinates) {
var i = 0,
n = coordinates.length,
j,
m,
resampled = n ? [coordinates[0]] : coordinates,
resamples,
origin = arc.source();
while (++i < n) {
resamples = arc.source(coordinates[i - 1])(coordinates[i]).coordinates;
for (j = 0, m = resamples.length; ++j < m;) resampled.push(resamples[j]);
}
arc.source(origin);
return resampled;
}
circle.origin = function(x) {
if (!arguments.length) return origin;
origin = x;
return circle;
};
circle.angle = function(x) {
if (!arguments.length) return degrees;
radians = (degrees = +x) * d3_geo_radians;
return circle;
};
// Precision is specified in degrees.
circle.precision = function(x) {
if (!arguments.length) return arc.precision();
arc.precision(x);
return circle;
};
return circle;
}