Files
openlayers/src/ol/coordinate.js
2016-04-04 09:43:24 +02:00

367 lines
11 KiB
JavaScript
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
goog.provide('ol.Coordinate');
goog.provide('ol.CoordinateFormatType');
goog.provide('ol.coordinate');
goog.require('goog.string');
goog.require('ol.math');
/**
* A function that takes a {@link ol.Coordinate} and transforms it into a
* `{string}`.
*
* @typedef {function((ol.Coordinate|undefined)): string}
* @api stable
*/
ol.CoordinateFormatType;
/**
* An array of numbers representing an xy coordinate. Example: `[16, 48]`.
* @typedef {Array.<number>} ol.Coordinate
* @api stable
*/
ol.Coordinate;
/**
* Add `delta` to `coordinate`. `coordinate` is modified in place and returned
* by the function.
*
* Example:
*
* var coord = [7.85, 47.983333];
* ol.coordinate.add(coord, [-2, 4]);
* // coord is now [5.85, 51.983333]
*
* @param {ol.Coordinate} coordinate Coordinate.
* @param {ol.Coordinate} delta Delta.
* @return {ol.Coordinate} The input coordinate adjusted by the given delta.
* @api stable
*/
ol.coordinate.add = function(coordinate, delta) {
coordinate[0] += delta[0];
coordinate[1] += delta[1];
return coordinate;
};
/**
* Calculates the point closest to the passed coordinate on the passed segment.
* This is the foot of the perpendicular of the coordinate to the segment when
* the foot is on the segment, or the closest segment coordinate when the foot
* is outside the segment.
*
* @param {ol.Coordinate} coordinate The coordinate.
* @param {Array.<ol.Coordinate>} segment The two coordinates of the segment.
* @return {ol.Coordinate} The foot of the perpendicular of the coordinate to
* the segment.
*/
ol.coordinate.closestOnSegment = function(coordinate, segment) {
var x0 = coordinate[0];
var y0 = coordinate[1];
var start = segment[0];
var end = segment[1];
var x1 = start[0];
var y1 = start[1];
var x2 = end[0];
var y2 = end[1];
var dx = x2 - x1;
var dy = y2 - y1;
var along = (dx === 0 && dy === 0) ? 0 :
((dx * (x0 - x1)) + (dy * (y0 - y1))) / ((dx * dx + dy * dy) || 0);
var x, y;
if (along <= 0) {
x = x1;
y = y1;
} else if (along >= 1) {
x = x2;
y = y2;
} else {
x = x1 + along * dx;
y = y1 + along * dy;
}
return [x, y];
};
/**
* Returns a {@link ol.CoordinateFormatType} function that can be used to format
* a {ol.Coordinate} to a string.
*
* Example without specifying the fractional digits:
*
* var coord = [7.85, 47.983333];
* var stringifyFunc = ol.coordinate.createStringXY();
* var out = stringifyFunc(coord);
* // out is now '8, 48'
*
* Example with explicitly specifying 2 fractional digits:
*
* var coord = [7.85, 47.983333];
* var stringifyFunc = ol.coordinate.createStringXY(2);
* var out = stringifyFunc(coord);
* // out is now '7.85, 47.98'
*
* @param {number=} opt_fractionDigits The number of digits to include
* after the decimal point. Default is `0`.
* @return {ol.CoordinateFormatType} Coordinate format.
* @api stable
*/
ol.coordinate.createStringXY = function(opt_fractionDigits) {
return (
/**
* @param {ol.Coordinate|undefined} coordinate Coordinate.
* @return {string} String XY.
*/
function(coordinate) {
return ol.coordinate.toStringXY(coordinate, opt_fractionDigits);
});
};
/**
* @private
* @param {number} degrees Degrees.
* @param {string} hemispheres Hemispheres.
* @param {number=} opt_fractionDigits The number of digits to include
* after the decimal point. Default is `0`.
* @return {string} String.
*/
ol.coordinate.degreesToStringHDMS_ = function(degrees, hemispheres, opt_fractionDigits) {
var normalizedDegrees = ol.math.modulo(degrees + 180, 360) - 180;
var x = Math.abs(3600 * normalizedDegrees);
var dflPrecision = opt_fractionDigits || 0;
return Math.floor(x / 3600) + '\u00b0 ' +
goog.string.padNumber(Math.floor((x / 60) % 60), 2) + '\u2032 ' +
goog.string.padNumber((x % 60), 2, dflPrecision) + '\u2033 ' +
hemispheres.charAt(normalizedDegrees < 0 ? 1 : 0);
};
/**
* Transforms the given {@link ol.Coordinate} to a string using the given string
* template. The strings `{x}` and `{y}` in the template will be replaced with
* the first and second coordinate values respectively.
*
* Example without specifying the fractional digits:
*
* var coord = [7.85, 47.983333];
* var template = 'Coordinate is ({x}|{y}).';
* var out = ol.coordinate.format(coord, template);
* // out is now 'Coordinate is (8|48).'
*
* Example explicitly specifying the fractional digits:
*
* var coord = [7.85, 47.983333];
* var template = 'Coordinate is ({x}|{y}).';
* var out = ol.coordinate.format(coord, template, 2);
* // out is now 'Coordinate is (7.85|47.98).'
*
* @param {ol.Coordinate|undefined} coordinate Coordinate.
* @param {string} template A template string with `{x}` and `{y}` placeholders
* that will be replaced by first and second coordinate values.
* @param {number=} opt_fractionDigits The number of digits to include
* after the decimal point. Default is `0`.
* @return {string} Formatted coordinate.
* @api stable
*/
ol.coordinate.format = function(coordinate, template, opt_fractionDigits) {
if (coordinate) {
return template
.replace('{x}', coordinate[0].toFixed(opt_fractionDigits))
.replace('{y}', coordinate[1].toFixed(opt_fractionDigits));
} else {
return '';
}
};
/**
* @param {ol.Coordinate} coordinate1 First coordinate.
* @param {ol.Coordinate} coordinate2 Second coordinate.
* @return {boolean} Whether the passed coordinates are equal.
*/
ol.coordinate.equals = function(coordinate1, coordinate2) {
var equals = true;
for (var i = coordinate1.length - 1; i >= 0; --i) {
if (coordinate1[i] != coordinate2[i]) {
equals = false;
break;
}
}
return equals;
};
/**
* Rotate `coordinate` by `angle`. `coordinate` is modified in place and
* returned by the function.
*
* Example:
*
* var coord = [7.85, 47.983333];
* var rotateRadians = Math.PI / 2; // 90 degrees
* ol.coordinate.rotate(coord, rotateRadians);
* // coord is now [-47.983333, 7.85]
*
* @param {ol.Coordinate} coordinate Coordinate.
* @param {number} angle Angle in radian.
* @return {ol.Coordinate} Coordinate.
* @api stable
*/
ol.coordinate.rotate = function(coordinate, angle) {
var cosAngle = Math.cos(angle);
var sinAngle = Math.sin(angle);
var x = coordinate[0] * cosAngle - coordinate[1] * sinAngle;
var y = coordinate[1] * cosAngle + coordinate[0] * sinAngle;
coordinate[0] = x;
coordinate[1] = y;
return coordinate;
};
/**
* Scale `coordinate` by `scale`. `coordinate` is modified in place and returned
* by the function.
*
* Example:
*
* var coord = [7.85, 47.983333];
* var scale = 1.2;
* ol.coordinate.scale(coord, scale);
* // coord is now [9.42, 57.5799996]
*
* @param {ol.Coordinate} coordinate Coordinate.
* @param {number} scale Scale factor.
* @return {ol.Coordinate} Coordinate.
*/
ol.coordinate.scale = function(coordinate, scale) {
coordinate[0] *= scale;
coordinate[1] *= scale;
return coordinate;
};
/**
* Subtract `delta` to `coordinate`. `coordinate` is modified in place and
* returned by the function.
*
* @param {ol.Coordinate} coordinate Coordinate.
* @param {ol.Coordinate} delta Delta.
* @return {ol.Coordinate} Coordinate.
*/
ol.coordinate.sub = function(coordinate, delta) {
coordinate[0] -= delta[0];
coordinate[1] -= delta[1];
return coordinate;
};
/**
* @param {ol.Coordinate} coord1 First coordinate.
* @param {ol.Coordinate} coord2 Second coordinate.
* @return {number} Squared distance between coord1 and coord2.
*/
ol.coordinate.squaredDistance = function(coord1, coord2) {
var dx = coord1[0] - coord2[0];
var dy = coord1[1] - coord2[1];
return dx * dx + dy * dy;
};
/**
* Calculate the squared distance from a coordinate to a line segment.
*
* @param {ol.Coordinate} coordinate Coordinate of the point.
* @param {Array.<ol.Coordinate>} segment Line segment (2 coordinates).
* @return {number} Squared distance from the point to the line segment.
*/
ol.coordinate.squaredDistanceToSegment = function(coordinate, segment) {
return ol.coordinate.squaredDistance(coordinate,
ol.coordinate.closestOnSegment(coordinate, segment));
};
/**
* Format a geographic coordinate with the hemisphere, degrees, minutes, and
* seconds.
*
* Example without specifying fractional digits:
*
* var coord = [7.85, 47.983333];
* var out = ol.coordinate.toStringHDMS(coord);
* // out is now '47° 58 60″ N 7° 50 60″ E'
*
* Example explicitly specifying 1 fractional digit:
*
* var coord = [7.85, 47.983333];
* var out = ol.coordinate.toStringHDMS(coord, 1);
* // out is now '47° 58 60.0″ N 7° 50 60.0″ E'
*
* @param {ol.Coordinate|undefined} coordinate Coordinate.
* @param {number=} opt_fractionDigits The number of digits to include
* after the decimal point. Default is `0`.
* @return {string} Hemisphere, degrees, minutes and seconds.
* @api stable
*/
ol.coordinate.toStringHDMS = function(coordinate, opt_fractionDigits) {
if (coordinate) {
return ol.coordinate.degreesToStringHDMS_(coordinate[1], 'NS', opt_fractionDigits) + ' ' +
ol.coordinate.degreesToStringHDMS_(coordinate[0], 'EW', opt_fractionDigits);
} else {
return '';
}
};
/**
* Format a coordinate as a comma delimited string.
*
* Example without specifying fractional digits:
*
* var coord = [7.85, 47.983333];
* var out = ol.coordinate.toStringXY(coord);
* // out is now '8, 48'
*
* Example explicitly specifying 1 fractional digit:
*
* var coord = [7.85, 47.983333];
* var out = ol.coordinate.toStringXY(coord, 1);
* // out is now '7.8, 48.0'
*
* @param {ol.Coordinate|undefined} coordinate Coordinate.
* @param {number=} opt_fractionDigits The number of digits to include
* after the decimal point. Default is `0`.
* @return {string} XY.
* @api stable
*/
ol.coordinate.toStringXY = function(coordinate, opt_fractionDigits) {
return ol.coordinate.format(coordinate, '{x}, {y}', opt_fractionDigits);
};
/**
* Create an ol.Coordinate from an Array and take into account axis order.
*
* Examples:
*
* var northCoord = ol.coordinate.fromProjectedArray([1, 2], 'n');
* // northCoord is now [2, 1]
*
* var eastCoord = ol.coordinate.fromProjectedArray([1, 2], 'e');
* // eastCoord is now [1, 2]
*
* @param {Array} array The array with coordinates.
* @param {string} axis the axis info.
* @return {ol.Coordinate} The coordinate created.
*/
ol.coordinate.fromProjectedArray = function(array, axis) {
var firstAxis = axis.charAt(0);
if (firstAxis === 'n' || firstAxis === 's') {
return [array[1], array[0]];
} else {
return array;
}
};