Files
openlayers/src/ol/geom/flat/length.js
Tim Schaub ad62739a6e Use blocked scoped variables
In addition to using const and let, this also upgrades our linter config and removes lint (mostly whitespace).
2018-01-12 00:50:30 -07:00

46 lines
1.3 KiB
JavaScript

/**
* @module ol/geom/flat/length
*/
const _ol_geom_flat_length_ = {};
/**
* @param {Array.<number>} flatCoordinates Flat coordinates.
* @param {number} offset Offset.
* @param {number} end End.
* @param {number} stride Stride.
* @return {number} Length.
*/
_ol_geom_flat_length_.lineString = function(flatCoordinates, offset, end, stride) {
let x1 = flatCoordinates[offset];
let y1 = flatCoordinates[offset + 1];
let length = 0;
let i;
for (i = offset + stride; i < end; i += stride) {
const x2 = flatCoordinates[i];
const y2 = flatCoordinates[i + 1];
length += Math.sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
x1 = x2;
y1 = y2;
}
return length;
};
/**
* @param {Array.<number>} flatCoordinates Flat coordinates.
* @param {number} offset Offset.
* @param {number} end End.
* @param {number} stride Stride.
* @return {number} Perimeter.
*/
_ol_geom_flat_length_.linearRing = function(flatCoordinates, offset, end, stride) {
let perimeter =
_ol_geom_flat_length_.lineString(flatCoordinates, offset, end, stride);
const dx = flatCoordinates[end - stride] - flatCoordinates[offset];
const dy = flatCoordinates[end - stride + 1] - flatCoordinates[offset + 1];
perimeter += Math.sqrt(dx * dx + dy * dy);
return perimeter;
};
export default _ol_geom_flat_length_;