Files
openlayers/src/ol/interaction/altdragrotate.js
Tom Payne f8c31ba45c s/ol3/ol/
2012-09-24 14:21:41 +02:00

61 lines
1.4 KiB
JavaScript

goog.provide('ol.interaction.AltDragRotate');
goog.require('ol.MapBrowserEvent');
goog.require('ol.interaction.Drag');
/**
* @constructor
* @extends {ol.interaction.Drag}
* @param {ol.interaction.Constraints} constraints Constraints.
*/
ol.interaction.AltDragRotate = function(constraints) {
goog.base(this, constraints);
/**
* @private
* @type {number}
*/
this.startRotation_ = 0;
};
goog.inherits(ol.interaction.AltDragRotate, ol.interaction.Drag);
/**
* @inheritDoc
*/
ol.interaction.AltDragRotate.prototype.handleDrag = function(mapBrowserEvent) {
var browserEvent = mapBrowserEvent.browserEvent;
var map = mapBrowserEvent.map;
var size = map.getSize();
var theta = Math.atan2(
size.height / 2 - browserEvent.offsetY,
browserEvent.offsetX - size.width / 2);
this.rotate(map, this.startRotation_, -theta);
};
/**
* @inheritDoc
*/
ol.interaction.AltDragRotate.prototype.handleDragStart =
function(mapBrowserEvent) {
var browserEvent = mapBrowserEvent.browserEvent;
var map = mapBrowserEvent.map;
if (browserEvent.isMouseActionButton() && browserEvent.altKey &&
map.canRotate()) {
var size = map.getSize();
var theta = Math.atan2(
size.height / 2 - browserEvent.offsetY,
browserEvent.offsetX - size.width / 2);
this.startRotation_ = (map.getRotation() || 0) + theta;
browserEvent.preventDefault();
return true;
} else {
return false;
}
};