diff --git a/examples/data/arrow.png b/examples/data/arrow.png new file mode 100644 index 0000000000..a0d3834586 Binary files /dev/null and b/examples/data/arrow.png differ diff --git a/examples/line-arrows.html b/examples/line-arrows.html new file mode 100644 index 0000000000..6338653387 --- /dev/null +++ b/examples/line-arrows.html @@ -0,0 +1,51 @@ + + + + + + + + + + + LineString arrows example + + + +
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+ OpenLayers 3 Examples +
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LineString arrows example

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Example of drawing arrows for each line string segment.

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See the line-arrows.js source to see how this is done.

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draw, vector, arrow
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+ + + + + + + diff --git a/examples/line-arrows.js b/examples/line-arrows.js new file mode 100644 index 0000000000..90f810acfa --- /dev/null +++ b/examples/line-arrows.js @@ -0,0 +1,67 @@ +goog.require('ol.Map'); +goog.require('ol.View'); +goog.require('ol.geom.Point'); +goog.require('ol.interaction.Draw'); +goog.require('ol.layer.Tile'); +goog.require('ol.layer.Vector'); +goog.require('ol.source.MapQuest'); +goog.require('ol.source.Vector'); +goog.require('ol.style.Icon'); +goog.require('ol.style.Stroke'); +goog.require('ol.style.Style'); + +var raster = new ol.layer.Tile({ + source: new ol.source.MapQuest({layer: 'sat'}) +}); + +var source = new ol.source.Vector(); + +var styleFunction = function(feature, resolution) { + var geometry = feature.getGeometry(); + var styles = [ + // linestring + new ol.style.Style({ + stroke: new ol.style.Stroke({ + color: '#ffcc33', + width: 2 + }) + }) + ]; + + geometry.forEachSegment(function(start, end) { + var dx = end[0] - start[0]; + var dy = end[1] - start[1]; + var rotation = Math.atan2(dy, dx); + // arrows + styles.push(new ol.style.Style({ + geometry: new ol.geom.Point(end), + image: new ol.style.Icon({ + src: 'data/arrow.png', + anchor: [0.75, 0.5], + rotateWithView: false, + rotation: -rotation + }) + })); + }); + + return styles; +}; +var vector = new ol.layer.Vector({ + source: source, + style: styleFunction +}); + +var map = new ol.Map({ + layers: [raster, vector], + renderer: exampleNS.getRendererFromQueryString(), + target: 'map', + view: new ol.View({ + center: [-11000000, 4600000], + zoom: 4 + }) +}); + +map.addInteraction(new ol.interaction.Draw({ + source: source, + type: /** @type {ol.geom.GeometryType} */ ('LineString') +})); diff --git a/src/ol/geom/flat/segmentsflatgeom.js b/src/ol/geom/flat/segmentsflatgeom.js index 8c6aac24fd..b834eecbdc 100644 --- a/src/ol/geom/flat/segmentsflatgeom.js +++ b/src/ol/geom/flat/segmentsflatgeom.js @@ -9,20 +9,22 @@ goog.provide('ol.geom.flat.segments'); * @param {number} offset Offset. * @param {number} end End. * @param {number} stride Stride. - * @param {function(ol.Coordinate, ol.Coordinate): T} callback Function + * @param {function(this: S, ol.Coordinate, ol.Coordinate): T} callback Function * called for each segment. + * @param {S=} opt_this The object to be used as the value of 'this' + * within callback. * @return {T|boolean} Value. - * @template T + * @template T,S */ ol.geom.flat.segments.forEach = - function(flatCoordinates, offset, end, stride, callback) { + function(flatCoordinates, offset, end, stride, callback, opt_this) { var point1 = [flatCoordinates[offset], flatCoordinates[offset + 1]]; var point2 = []; var ret; for (; (offset + stride) < end; offset += stride) { point2[0] = flatCoordinates[offset + stride]; point2[1] = flatCoordinates[offset + stride + 1]; - ret = callback(point1, point2); + ret = callback.call(opt_this, point1, point2); if (ret) { return ret; } diff --git a/src/ol/geom/linestring.js b/src/ol/geom/linestring.js index 3477285f3c..08c99fc771 100644 --- a/src/ol/geom/linestring.js +++ b/src/ol/geom/linestring.js @@ -11,6 +11,7 @@ goog.require('ol.geom.flat.inflate'); goog.require('ol.geom.flat.interpolate'); goog.require('ol.geom.flat.intersectsextent'); goog.require('ol.geom.flat.length'); +goog.require('ol.geom.flat.segments'); goog.require('ol.geom.flat.simplify'); @@ -107,6 +108,25 @@ ol.geom.LineString.prototype.closestPointXY = }; +/** + * Iterate over each segment, calling the provided callback. + * If the callback returns a truthy value the function returns that + * value immediately. Otherwise the function returns `false`. + * + * @param {function(this: S, ol.Coordinate, ol.Coordinate): T} callback Function + * called for each segment. + * @param {S=} opt_this The object to be used as the value of 'this' + * within callback. + * @return {T|boolean} Value. + * @template T,S + * @api + */ +ol.geom.LineString.prototype.forEachSegment = function(callback, opt_this) { + return ol.geom.flat.segments.forEach(this.flatCoordinates, 0, + this.flatCoordinates.length, this.stride, callback, opt_this); +}; + + /** * Returns the coordinate at `m` using linear interpolation, or `null` if no * such coordinate exists.