CartoDB-SQL-API/spike/public/map.js
2012-04-10 12:53:38 +01:00

267 lines
7.8 KiB
JavaScript

window.requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function( callback ){
window.setTimeout(callback, 1000 / 60);
};
})();
function Event() {}
Event.prototype.on = function(evt, callback) {
var cb = this.callbacks = this.callbacks || {};
var l = cb[evt] || (cb[evt] = []);
l.push(callback);
};
Event.prototype.emit = function(evt) {
var c = this.callbacks && this.callbacks[evt];
for(var i = 0; c && i < c.length; ++i) {
c[i].apply(this, Array.prototype.slice.call(arguments, 1));
}
};
function MapModel(opts) {
opts = opts || {};
this.projection = new MercatorProjection();
this.setCenter(opts.center || new LatLng(0,0));
this.setZoom(opts.zoom || 1);
}
MapModel.prototype = new Event();
MapModel.prototype.setCenter = function(center) {
this.center = new LatLng(center.lat, center.lng);
this.center_pixel = this.projection.fromLatLngToPixel(this.center, this.zoom).floor();
this.emit('center_changed', this.center);
};
MapModel.prototype.setZoom = function(zoom) {
this.zoom = zoom;
this.center_pixel = this.projection.fromLatLngToPixel(this.center, this.zoom).floor();
this.emit('zoom_changed', this.center);
};
MapModel.prototype.getCenterPixel = function() {
var center_point = this.projection.fromLatLngToPixel(this.center, this.zoom);
return center_point;
}
MapModel.prototype.getTopLeft = function(width, height) {
var center_point = this.projection.fromLatLngToPixel(this.center, this.zoom);
var widthHalf = width / 2;
var heightHalf = height / 2;
center_point.x -= widthHalf;
center_point.y -= heightHalf;
return center_point;
}
MapModel.prototype.getBBox = function(width, height) {
var center_point = this.projection.fromLatLngToPixel(this.center, this.zoom);
var widthHalf = width / 2;
var heightHalf = height / 2;
center_point.x -= widthHalf;
center_point.y += heightHalf;
var bottomleft = this.projection.fromPixelToLatLng(center_point, this.zoom);
center_point.x += width;
center_point.y -= height;
var topRight = this.projection.fromPixelToLatLng(center_point, this.zoom);
return [bottomleft, topRight]
}
/**
* return a list of tiles inside the spcified zone
* the center will be placed on the center of that zone
*/
MapModel.prototype.visibleTiles = function(width, height) {
var self = this;
var widthHalf = width / 2;
var heightHalf = height / 2;
var center_point = self.projection.fromLatLngToPixel(self.center, self.zoom);
center_point.x -= widthHalf;
center_point.y -= heightHalf;
var tile = this.projection.pixelToTile(center_point, self.zoom);
var offset_x = center_point.x%this.projection.TILE_SIZE;
var offset_y = center_point.y%this.projection.TILE_SIZE;
var num_tiles_x = Math.ceil((width + offset_x)/this.projection.TILE_SIZE);
var num_tiles_y = Math.ceil((height + offset_y)/this.projection.TILE_SIZE);
var tiles = [];
for(var i = 0; i < num_tiles_x; ++i) {
for(var j = 0; j < num_tiles_y; ++j) {
var tile_x = tile.x + i;
var tile_y = tile.y + j;
tiles.push({
x: tile_x * this.projection.TILE_SIZE,
y: tile_y * this.projection.TILE_SIZE,
zoom: self.zoom,
i: tile_x,
j: tile_y
});
}
}
return tiles;
}
function dragger(el) {
var self = this;
var dragging = false;
var x, y;
el.ontouchstart = el.onmousedown = function(e) {
dragging = true;
if (e.touches) {
var p = e.touches[0];
x = p.pageX;
y = p.pageY;
} else {
x = e.clientX;
y = e.clientY;
}
self.emit('startdrag', x, y);
};
el.ontouchmove = el.onmousemove = function(e) {
var xx, yy;
if(!dragging) return;
if (e.touches) {
var p = e.touches[0];
xx = p.pageX;
yy = p.pageY;
} else {
xx = e.clientX;
yy = e.clientY;
}
self.emit('move', xx - x, yy - y);
return false;
};
el.ontouchend = el.onmouseup = function(e) {
dragging = false;
self.emit('enddrag', x, y);
};
}
dragger.prototype = new Event();
function CanvasRenderer(el, map) {
var self = this;
this.el = el;
this.tiles = {};
this.width = el.offsetWidth >> 0;
this.height = el.offsetHeight >> 0;
var widthHalf = (this.width / 2) >> 0;
var heightHalf = (this.height / 2) >> 0;
var canvas = this.canvas = document.createElement('canvas');
canvas.style.padding = '0';
canvas.style.margin= '0';
canvas.style.position = 'absolute';
canvas.width = this.width;
canvas.height = this.height;
var context = canvas.getContext( '2d' );
context.translate( widthHalf, heightHalf );
this.context = context;
var div = document.createElement('div');
div.style.width = this.width + "px";
div.style.height= this.height + "px";
div.style.position = 'relative';
div.appendChild(canvas);
el.appendChild(div);
this.center_init = null;
this.target_center = new LatLng();
this.drag = new dragger(div);
this.drag.on('startdrag', function() {
self.center_init = map.center.clone();
});
this.drag.on('enddrag', function() {
map.emit('end_move');
});
function go_to_target() {
var c = map.center;
var t = self.target_center;
var dlat = t.lat - c.lat;
var dlon = t.lng - c.lng;
t.lat += dlat*0.0001;
t.lng += dlon*0.0001;
map.setCenter(t);
if(Math.abs(dlat) + Math.abs(dlon) > 0.001) {
requestAnimFrame(go_to_target);
} else {
//map.emit('end_move');
}
}
this.drag.on('move', function(dx, dy) {
var t = 1 << map.zoom;
var s = 1/t;
s = s/map.projection.pixelsPerLonDegree_;
self.target_center.lat = self.center_init.lat + dy*s;
self.target_center.lng = self.center_init.lng - dx*s;
requestAnimFrame(go_to_target);
});
}
CanvasRenderer.prototype.renderTile = function(tile, at) {
var self = this;
var key = at.x + '_' + at.y
if(a=self.tiles[key]) {
self.context.drawImage(a, at.x, at.y);
return;
}
//var layer = 'http://a.tile.cloudmade.com/BC9A493B41014CAABB98F0471D759707/997/256/{{z}}/{{x}}/{{y}}.png';
var layer = 'http://b.tiles.mapbox.com/v3/mapbox.mapbox-light/{{z}}/{{x}}/{{y}}.png64';
var url = layer.replace('{{z}}', tile.zoom).replace('{{x}}', tile.i).replace('{{y}}', tile.j);
var img = new Image();
img.src = url;
img.onload = function() {
self.context.drawImage(img, at.x, at.y);
self.tiles[key] = img;
};
}
CanvasRenderer.prototype.renderTiles = function(tiles, center) {
for(var i = 0; i < tiles.length; ++i) {
var tile = tiles[i];
var p = new Point(tile.x, tile.y);
p.x -= center.x;
p.y -= center.y;
this.renderTile(tile, p);
}
}
function Map(el, opts) {
opts = opts || {};
var self = this;
this.model = new MapModel({
center: opts.center || new LatLng(41.69, -4.83),
zoom: opts.zoom || 1
});
this.view = new CanvasRenderer(el, this.model);
/*function render() {
var tiles = self.model.visibleTiles(self.view.width, self.view.height);
self.view.renderTiles(tiles, this.center_pixel);
}
this.model.on('center_changed', render);
this.model.on('zoom_changed', render);
this.model.emit('center_changed');
*/
}