CalvinBackup/iD
1
0
Fork 0
mirror of https://github.com/FoggedLens/iD.git synced 2026-02-13 09:12:52 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add iD.geo.sphericalDistance

Browse Source 
iD.geo.euclideanDistance should only be used for calculations of 
projected coordinates or display (pixel) coordinates.

iD.geo.sphericalDistance calculates approximate geographical 
distances, accounting for distortions at higher latitudes. This 
can be used for determining the nearest node (operations.Delete,
actions.Circularize) or relative length comparisons (actions.Split).
This commit is contained in:
tyr
2013-09-12 13:55:07 +02:00
committed by John Firebaugh
parent 6afe3adfbe
commit e8d637f2bb
11 changed files with 55 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
js/id/actions/circularize.js
View File

@@ -8,7 +8,7 @@ iD.actions.Circularize = function(wayId, projection, maxAngle) {
points = nodes.map(function(n) { return projection(n.loc); }),
keyPoints = keyNodes.map(function(n) { return projection(n.loc); }),
centroid = d3.geom.polygon(points).centroid(),
radius = d3.median(points, function(p) { return iD.geo.dist(centroid, p); }),
radius = d3.median(points, function(p) { return iD.geo.euclideanDistance(centroid, p); }),
sign = d3.geom.polygon(points).area() > 0 ? 1 : -1,
ids;
@@ -44,7 +44,7 @@ iD.actions.Circularize = function(wayId, projection, maxAngle) {
}
// position this key node
distance = iD.geo.dist(centroid, keyPoints[i]);
distance = iD.geo.euclideanDistance(centroid, keyPoints[i]);
keyPoints[i] = [
centroid[0] + (keyPoints[i][0] - centroid[0]) / distance * radius,
centroid[1] + (keyPoints[i][1] - centroid[1]) / distance * radius];

2
js/id/actions/orthogonalize.js
View File

@@ -84,7 +84,7 @@ iD.actions.Orthogonalize = function(wayId, projection) {
p = subtractPoints(a, b),
q = subtractPoints(c, b);
var scale = 2*Math.min(iD.geo.dist(p, [0, 0]), iD.geo.dist(q, [0, 0]));
var scale = 2*Math.min(iD.geo.euclideanDistance(p, [0, 0]), iD.geo.euclideanDistance(q, [0, 0]));
p = normalizePoint(p, 1.0);
q = normalizePoint(q, 1.0);

2
js/id/actions/split.js
View File

@@ -44,7 +44,7 @@ iD.actions.Split = function(nodeId, newWayIds) {
return iD.util.wrap(index,nodes.length);
}
function _dist(nA, nB) {
return iD.geo.dist(graph.entity(nA).loc, graph.entity(nB).loc);
return iD.geo.sphericalDistance(graph.entity(nA).loc, graph.entity(nB).loc);
}
// calculate lengths

4
js/id/behavior/draw.js
View File

@@ -34,8 +34,8 @@ iD.behavior.Draw = function(context) {
d3.select(window).on('mouseup.draw', function() {
element.on('mousemove.draw', mousemove);
if (iD.geo.dist(pos, point()) < closeTolerance ||
(iD.geo.dist(pos, point()) < tolerance &&
if (iD.geo.euclideanDistance(pos, point()) < closeTolerance ||
(iD.geo.euclideanDistance(pos, point()) < tolerance &&
(+new Date() - time) < 500)) {
// Prevent a quick second click

10
js/id/geo.js
View File

@@ -10,17 +10,23 @@ iD.geo.interp = function(p1, p2, t) {
};
// http://jsperf.com/id-dist-optimization
iD.geo.dist = function(a, b) {
iD.geo.euclideanDistance = function(a, b) {
var x = a[0] - b[0], y = a[1] - b[1];
return Math.sqrt((x * x) + (y * y));
};
// Equirectangular approximation of spherical distances on Earth
iD.geo.sphericalDistance = function(a, b) {
var x = Math.cos(a[1]*Math.PI/180) * (a[0] - b[0]),
y = a[1] - b[1];
return 6.3710E6 * Math.sqrt((x * x) + (y * y)) * Math.PI/180;
};
// Choose the edge with the minimal distance from `point` to its orthogonal
// projection onto that edge, if such a projection exists, or the distance to
// the closest vertex on that edge. Returns an object with the `index` of the
// chosen edge, the chosen `loc` on that edge, and the `distance` to to it.
iD.geo.chooseEdge = function(nodes, point, projection) {
var dist = iD.geo.dist,
var dist = iD.geo.euclideanDistance,
points = nodes.map(function(n) { return projection(n.loc); }),
min = Infinity,
idx, loc;

4
js/id/operations/delete.js
View File

@@ -27,8 +27,8 @@ iD.operations.Delete = function(selectedIDs, context) {
} else if (i === nodes.length - 1) {
i--;
} else {
var a = iD.geo.dist(entity.loc, context.entity(nodes[i - 1]).loc),
b = iD.geo.dist(entity.loc, context.entity(nodes[i + 1]).loc);
var a = iD.geo.sphericalDistance(entity.loc, context.entity(nodes[i - 1]).loc),
b = iD.geo.sphericalDistance(entity.loc, context.entity(nodes[i + 1]).loc);
i = a < b ? i - 1 : i + 1;
}

2
js/id/svg.js
View File

@@ -63,7 +63,7 @@ iD.svg = {
b = [x, y];
if (a) {
var span = iD.geo.dist(a, b) - offset;
var span = iD.geo.euclideanDistance(a, b) - offset;
if (span >= 0) {
var angle = Math.atan2(b[1] - a[1], b[0] - a[0]),

2
js/id/svg/midpoints.js
View File

@@ -20,7 +20,7 @@ iD.svg.Midpoints = function(projection, context) {
// If neither of the nodes changed, no need to redraw midpoint
if (!midpoints[id] && (filter(a) || filter(b))) {
var loc = iD.geo.interp(a.loc, b.loc, 0.5);
if (extent.intersects(loc) && iD.geo.dist(projection(a.loc), projection(b.loc)) > 40) {
if (extent.intersects(loc) && iD.geo.euclideanDistance(projection(a.loc), projection(b.loc)) > 40) {
midpoints[id] = {
type: 'midpoint',
id: id,

6
test/spec/actions/circularize.js
View File

@@ -48,7 +48,7 @@ describe("iD.actions.Circularize", function () {
graph = iD.actions.Circularize('-', projection)(graph);
expect(iD.geo.dist(graph.entity('d').loc, [2, -2])).to.be.lt(0.5);
expect(iD.geo.euclideanDistance(graph.entity('d').loc, [2, -2])).to.be.lt(0.5);
});
function angle(point1, point2, center) {
@@ -56,10 +56,10 @@ describe("iD.actions.Circularize", function () {
vector2 = [point2[0] - center[0], point2[1] - center[1]],
distance;
distance = iD.geo.dist(vector1, [0, 0]);
distance = iD.geo.euclideanDistance(vector1, [0, 0]);
vector1 = [vector1[0] / distance, vector1[1] / distance];
distance = iD.geo.dist(vector2, [0, 0]);
distance = iD.geo.euclideanDistance(vector2, [0, 0]);
vector2 = [vector2[0] / distance, vector2[1] / distance];
return 180 / Math.PI * Math.acos(vector1[0] * vector2[0] + vector1[1] * vector2[1]);

4
test/spec/actions/orthogonalize.js
View File

@@ -97,12 +97,12 @@ describe("iD.actions.Orthogonalize", function () {
'd': iD.Node({id: 'd', loc: tests[i][3]}),
'-': iD.Way({id: '-', nodes: ['a', 'b', 'c', 'd', 'a']})
}),
initialWidth = iD.geo.dist(graph.entity('a').loc, graph.entity('b').loc),
initialWidth = iD.geo.sphericalDistance(graph.entity('a').loc, graph.entity('b').loc),
finalWidth;
graph = iD.actions.Orthogonalize('-', projection)(graph);
finalWidth = iD.geo.dist(graph.entity('a').loc, graph.entity('b').loc);
finalWidth = iD.geo.sphericalDistance(graph.entity('a').loc, graph.entity('b').loc);
expect(finalWidth / initialWidth).within(0.90, 1.10);
}
});

36
test/spec/geo.js
View File

@@ -18,21 +18,49 @@ describe('iD.geo', function() {
});
});
describe('.dist', function() {
describe('.euclideanDistance', function() {
it('distance between two same points is zero', function() {
var a = [0, 0],
b = [0, 0];
expect(iD.geo.dist(a, b)).to.eql(0);
expect(iD.geo.euclideanDistance(a, b)).to.eql(0);
});
it('a straight 10 unit line is 10', function() {
var a = [0, 0],
b = [10, 0];
expect(iD.geo.dist(a, b)).to.eql(10);
expect(iD.geo.euclideanDistance(a, b)).to.eql(10);
});
it('a pythagorean triangle is right', function() {
var a = [0, 0],
b = [4, 3];
expect(iD.geo.dist(a, b)).to.eql(5);
expect(iD.geo.euclideanDistance(a, b)).to.eql(5);
});
});
describe('.sphericalDistance', function() {
it('distance between two same points is zero', function() {
var a = [0, 0],
b = [0, 0];
expect(iD.geo.sphericalDistance(a, b)).to.eql(0);
});
it('a straight 1 degree line at the equator is aproximately 111 km', function() {
var a = [0, 0],
b = [1, 0];
expect(iD.geo.sphericalDistance(a, b)).to.be.within(100E3,120E3);
});
it('a pythagorean triangle is right', function() {
var a = [0, 0],
b = [4, 3];
expect(iD.geo.sphericalDistance(a, b)).to.be.within(500E3,600E3);
});
it('east-west distances at high latitude are shorter', function() {
var a = [0, 60],
b = [1, 60];
expect(iD.geo.sphericalDistance(a, b)).to.be.within(50E3,60E3);
});
it('north-south distances at high latitude are not shorter', function() {
var a = [0, 60],
b = [0, 61];
expect(iD.geo.sphericalDistance(a, b)).to.be.within(100E3,120E3);
});
});