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Refactor d3.geom.hull.
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@jasondavies
jasondavies committed Mar 19, 2013
1 parent cf56155 commit fd40dc2
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Showing 4 changed files with 305 additions and 199 deletions.
281 changes: 148 additions & 133 deletions d3.js
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Original file line number Diff line number Diff line change
Expand Up @@ -3660,139 +3660,6 @@ d3 = function() {
return d3_geo_projection(d3_geo_transverseMercator);
}).raw = d3_geo_transverseMercator;
d3.geom = {};
d3.geom.hull = function(vertices) {
if (vertices.length < 3) return [];
var len = vertices.length, plen = len - 1, points = [], stack = [], i, j, h = 0, x1, y1, x2, y2, u, v, a, sp;
for (i = 1; i < len; ++i) {
if (vertices[i][1] < vertices[h][1]) {
h = i;
} else if (vertices[i][1] == vertices[h][1]) {
h = vertices[i][0] < vertices[h][0] ? i : h;
}
}
for (i = 0; i < len; ++i) {
if (i === h) continue;
y1 = vertices[i][1] - vertices[h][1];
x1 = vertices[i][0] - vertices[h][0];
points.push({
angle: Math.atan2(y1, x1),
index: i
});
}
points.sort(function(a, b) {
return a.angle - b.angle;
});
a = points[0].angle;
v = points[0].index;
u = 0;
for (i = 1; i < plen; ++i) {
j = points[i].index;
if (a == points[i].angle) {
x1 = vertices[v][0] - vertices[h][0];
y1 = vertices[v][1] - vertices[h][1];
x2 = vertices[j][0] - vertices[h][0];
y2 = vertices[j][1] - vertices[h][1];
if (x1 * x1 + y1 * y1 >= x2 * x2 + y2 * y2) {
points[i].index = -1;
} else {
points[u].index = -1;
a = points[i].angle;
u = i;
v = j;
}
} else {
a = points[i].angle;
u = i;
v = j;
}
}
stack.push(h);
for (i = 0, j = 0; i < 2; ++j) {
if (points[j].index !== -1) {
stack.push(points[j].index);
i++;
}
}
sp = stack.length;
for (;j < plen; ++j) {
if (points[j].index === -1) continue;
while (!d3_geom_hullCCW(stack[sp - 2], stack[sp - 1], points[j].index, vertices)) {
--sp;
}
stack[sp++] = points[j].index;
}
var poly = [];
for (i = 0; i < sp; ++i) {
poly.push(vertices[stack[i]]);
}
return poly;
};
function d3_geom_hullCCW(i1, i2, i3, v) {
var t, a, b, c, d, e, f;
t = v[i1];
a = t[0];
b = t[1];
t = v[i2];
c = t[0];
d = t[1];
t = v[i3];
e = t[0];
f = t[1];
return (f - b) * (c - a) - (d - b) * (e - a) > 0;
}
d3.geom.polygon = function(coordinates) {
coordinates.area = function() {
var i = 0, n = coordinates.length, area = coordinates[n - 1][1] * coordinates[0][0] - coordinates[n - 1][0] * coordinates[0][1];
while (++i < n) {
area += coordinates[i - 1][1] * coordinates[i][0] - coordinates[i - 1][0] * coordinates[i][1];
}
return area * .5;
};
coordinates.centroid = function(k) {
var i = -1, n = coordinates.length, x = 0, y = 0, a, b = coordinates[n - 1], c;
if (!arguments.length) k = -1 / (6 * coordinates.area());
while (++i < n) {
a = b;
b = coordinates[i];
c = a[0] * b[1] - b[0] * a[1];
x += (a[0] + b[0]) * c;
y += (a[1] + b[1]) * c;
}
return [ x * k, y * k ];
};
coordinates.clip = function(subject) {
var input, i = -1, n = coordinates.length, j, m, a = coordinates[n - 1], b, c, d;
while (++i < n) {
input = subject.slice();
subject.length = 0;
b = coordinates[i];
c = input[(m = input.length) - 1];
j = -1;
while (++j < m) {
d = input[j];
if (d3_geom_polygonInside(d, a, b)) {
if (!d3_geom_polygonInside(c, a, b)) {
subject.push(d3_geom_polygonIntersect(c, d, a, b));
}
subject.push(d);
} else if (d3_geom_polygonInside(c, a, b)) {
subject.push(d3_geom_polygonIntersect(c, d, a, b));
}
c = d;
}
a = b;
}
return subject;
};
return coordinates;
};
function d3_geom_polygonInside(p, a, b) {
return (b[0] - a[0]) * (p[1] - a[1]) < (b[1] - a[1]) * (p[0] - a[0]);
}
function d3_geom_polygonIntersect(c, d, a, b) {
var x1 = c[0], x3 = a[0], x21 = d[0] - x1, x43 = b[0] - x3, y1 = c[1], y3 = a[1], y21 = d[1] - y1, y43 = b[1] - y3, ua = (x43 * (y1 - y3) - y43 * (x1 - x3)) / (y43 * x21 - x43 * y21);
return [ x1 + ua * x21, y1 + ua * y21 ];
}
d3.svg = {};
function d3_svg_line(projection) {
var x = d3_svg_lineX, y = d3_svg_lineY, defined = d3_true, interpolate = d3_svg_lineLinear, interpolateKey = interpolate.key, tension = .7;
Expand Down Expand Up @@ -4048,6 +3915,154 @@ d3 = function() {
function d3_svg_lineMonotone(points) {
return points.length < 3 ? d3_svg_lineLinear(points) : points[0] + d3_svg_lineHermite(points, d3_svg_lineMonotoneTangents(points));
}
d3.geom.hull = function(vertices) {
var x = d3_svg_lineX, y = d3_svg_lineY;
if (arguments.length) return hull(vertices);
function hull(data) {
if (data.length < 3) return [];
var fx = d3_functor(x), fy = d3_functor(y), n = data.length, vertices, plen = n - 1, points = [], stack = [], d, i, j, h = 0, x1, y1, x2, y2, u, v, a, sp;
if (fx === d3_svg_lineX && y === d3_svg_lineY) vertices = data; else for (i = 0,
vertices = []; i < n; ++i) {
vertices.push([ +fx.call(this, d = data[i], i), +fy.call(this, d, i) ]);
}
for (i = 1; i < n; ++i) {
if (vertices[i][1] < vertices[h][1]) {
h = i;
} else if (vertices[i][1] == vertices[h][1]) {
h = vertices[i][0] < vertices[h][0] ? i : h;
}
}
for (i = 0; i < n; ++i) {
if (i === h) continue;
y1 = vertices[i][1] - vertices[h][1];
x1 = vertices[i][0] - vertices[h][0];
points.push({
angle: Math.atan2(y1, x1),
index: i
});
}
points.sort(function(a, b) {
return a.angle - b.angle;
});
a = points[0].angle;
v = points[0].index;
u = 0;
for (i = 1; i < plen; ++i) {
j = points[i].index;
if (a == points[i].angle) {
x1 = vertices[v][0] - vertices[h][0];
y1 = vertices[v][1] - vertices[h][1];
x2 = vertices[j][0] - vertices[h][0];
y2 = vertices[j][1] - vertices[h][1];
if (x1 * x1 + y1 * y1 >= x2 * x2 + y2 * y2) {
points[i].index = -1;
} else {
points[u].index = -1;
a = points[i].angle;
u = i;
v = j;
}
} else {
a = points[i].angle;
u = i;
v = j;
}
}
stack.push(h);
for (i = 0, j = 0; i < 2; ++j) {
if (points[j].index !== -1) {
stack.push(points[j].index);
i++;
}
}
sp = stack.length;
for (;j < plen; ++j) {
if (points[j].index === -1) continue;
while (!d3_geom_hullCCW(stack[sp - 2], stack[sp - 1], points[j].index, vertices)) {
--sp;
}
stack[sp++] = points[j].index;
}
var poly = [];
for (i = 0; i < sp; ++i) {
poly.push(data[stack[i]]);
}
return poly;
}
hull.x = function(_) {
return arguments.length ? (x = _, hull) : x;
};
hull.y = function(_) {
return arguments.length ? (y = _, hull) : y;
};
return hull;
};
function d3_geom_hullCCW(i1, i2, i3, v) {
var t, a, b, c, d, e, f;
t = v[i1];
a = t[0];
b = t[1];
t = v[i2];
c = t[0];
d = t[1];
t = v[i3];
e = t[0];
f = t[1];
return (f - b) * (c - a) - (d - b) * (e - a) > 0;
}
d3.geom.polygon = function(coordinates) {
coordinates.area = function() {
var i = 0, n = coordinates.length, area = coordinates[n - 1][1] * coordinates[0][0] - coordinates[n - 1][0] * coordinates[0][1];
while (++i < n) {
area += coordinates[i - 1][1] * coordinates[i][0] - coordinates[i - 1][0] * coordinates[i][1];
}
return area * .5;
};
coordinates.centroid = function(k) {
var i = -1, n = coordinates.length, x = 0, y = 0, a, b = coordinates[n - 1], c;
if (!arguments.length) k = -1 / (6 * coordinates.area());
while (++i < n) {
a = b;
b = coordinates[i];
c = a[0] * b[1] - b[0] * a[1];
x += (a[0] + b[0]) * c;
y += (a[1] + b[1]) * c;
}
return [ x * k, y * k ];
};
coordinates.clip = function(subject) {
var input, i = -1, n = coordinates.length, j, m, a = coordinates[n - 1], b, c, d;
while (++i < n) {
input = subject.slice();
subject.length = 0;
b = coordinates[i];
c = input[(m = input.length) - 1];
j = -1;
while (++j < m) {
d = input[j];
if (d3_geom_polygonInside(d, a, b)) {
if (!d3_geom_polygonInside(c, a, b)) {
subject.push(d3_geom_polygonIntersect(c, d, a, b));
}
subject.push(d);
} else if (d3_geom_polygonInside(c, a, b)) {
subject.push(d3_geom_polygonIntersect(c, d, a, b));
}
c = d;
}
a = b;
}
return subject;
};
return coordinates;
};
function d3_geom_polygonInside(p, a, b) {
return (b[0] - a[0]) * (p[1] - a[1]) < (b[1] - a[1]) * (p[0] - a[0]);
}
function d3_geom_polygonIntersect(c, d, a, b) {
var x1 = c[0], x3 = a[0], x21 = d[0] - x1, x43 = b[0] - x3, y1 = c[1], y3 = a[1], y21 = d[1] - y1, y43 = b[1] - y3, ua = (x43 * (y1 - y3) - y43 * (x1 - x3)) / (y43 * x21 - x43 * y21);
return [ x1 + ua * x21, y1 + ua * y21 ];
}
d3.geom.delaunay = function(vertices) {
var edges = vertices.map(function() {
return [];
Expand Down
10 changes: 5 additions & 5 deletions d3.min.js
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