openlayers
Version:
Build tools and sources for developing OpenLayers based mapping applications
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JavaScript
goog.provide('ol.source.Zoomify');
goog.require('ol');
goog.require('ol.ImageTile');
goog.require('ol.Tile');
goog.require('ol.asserts');
goog.require('ol.dom');
goog.require('ol.extent');
goog.require('ol.source.TileImage');
goog.require('ol.tilegrid.TileGrid');
/**
* @classdesc
* Layer source for tile data in Zoomify format.
*
* @constructor
* @extends {ol.source.TileImage}
* @param {olx.source.ZoomifyOptions=} opt_options Options.
* @api stable
*/
ol.source.Zoomify = function(opt_options) {
var options = opt_options || {};
var size = options.size;
var tierSizeCalculation = options.tierSizeCalculation !== undefined ?
options.tierSizeCalculation :
ol.source.Zoomify.TierSizeCalculation.DEFAULT;
var imageWidth = size[0];
var imageHeight = size[1];
var tierSizeInTiles = [];
var tileSize = ol.DEFAULT_TILE_SIZE;
switch (tierSizeCalculation) {
case ol.source.Zoomify.TierSizeCalculation.DEFAULT:
while (imageWidth > tileSize || imageHeight > tileSize) {
tierSizeInTiles.push([
Math.ceil(imageWidth / tileSize),
Math.ceil(imageHeight / tileSize)
]);
tileSize += tileSize;
}
break;
case ol.source.Zoomify.TierSizeCalculation.TRUNCATED:
var width = imageWidth;
var height = imageHeight;
while (width > tileSize || height > tileSize) {
tierSizeInTiles.push([
Math.ceil(width / tileSize),
Math.ceil(height / tileSize)
]);
width >>= 1;
height >>= 1;
}
break;
default:
ol.asserts.assert(false, 53); // Unknown `tierSizeCalculation` configured
break;
}
tierSizeInTiles.push([1, 1]);
tierSizeInTiles.reverse();
var resolutions = [1];
var tileCountUpToTier = [0];
var i, ii;
for (i = 1, ii = tierSizeInTiles.length; i < ii; i++) {
resolutions.push(1 << i);
tileCountUpToTier.push(
tierSizeInTiles[i - 1][0] * tierSizeInTiles[i - 1][1] +
tileCountUpToTier[i - 1]
);
}
resolutions.reverse();
var extent = [0, -size[1], size[0], 0];
var tileGrid = new ol.tilegrid.TileGrid({
extent: extent,
origin: ol.extent.getTopLeft(extent),
resolutions: resolutions
});
var url = options.url;
/**
* @this {ol.source.TileImage}
* @param {ol.TileCoord} tileCoord Tile Coordinate.
* @param {number} pixelRatio Pixel ratio.
* @param {ol.proj.Projection} projection Projection.
* @return {string|undefined} Tile URL.
*/
function tileUrlFunction(tileCoord, pixelRatio, projection) {
if (!tileCoord) {
return undefined;
} else {
var tileCoordZ = tileCoord[0];
var tileCoordX = tileCoord[1];
var tileCoordY = -tileCoord[2] - 1;
var tileIndex =
tileCoordX +
tileCoordY * tierSizeInTiles[tileCoordZ][0] +
tileCountUpToTier[tileCoordZ];
var tileGroup = (tileIndex / ol.DEFAULT_TILE_SIZE) | 0;
return url + 'TileGroup' + tileGroup + '/' +
tileCoordZ + '-' + tileCoordX + '-' + tileCoordY + '.jpg';
}
}
ol.source.TileImage.call(this, {
attributions: options.attributions,
cacheSize: options.cacheSize,
crossOrigin: options.crossOrigin,
logo: options.logo,
reprojectionErrorThreshold: options.reprojectionErrorThreshold,
tileClass: ol.source.Zoomify.Tile_,
tileGrid: tileGrid,
tileUrlFunction: tileUrlFunction
});
};
ol.inherits(ol.source.Zoomify, ol.source.TileImage);
/**
* @constructor
* @extends {ol.ImageTile}
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @param {ol.Tile.State} state State.
* @param {string} src Image source URI.
* @param {?string} crossOrigin Cross origin.
* @param {ol.TileLoadFunctionType} tileLoadFunction Tile load function.
* @private
*/
ol.source.Zoomify.Tile_ = function(
tileCoord, state, src, crossOrigin, tileLoadFunction) {
ol.ImageTile.call(this, tileCoord, state, src, crossOrigin, tileLoadFunction);
/**
* @private
* @type {HTMLCanvasElement|HTMLImageElement|HTMLVideoElement}
*/
this.zoomifyImage_ = null;
};
ol.inherits(ol.source.Zoomify.Tile_, ol.ImageTile);
/**
* @inheritDoc
*/
ol.source.Zoomify.Tile_.prototype.getImage = function() {
if (this.zoomifyImage_) {
return this.zoomifyImage_;
}
var tileSize = ol.DEFAULT_TILE_SIZE;
var image = ol.ImageTile.prototype.getImage.call(this);
if (this.state == ol.Tile.State.LOADED) {
if (image.width == tileSize && image.height == tileSize) {
this.zoomifyImage_ = image;
return image;
} else {
var context = ol.dom.createCanvasContext2D(tileSize, tileSize);
context.drawImage(image, 0, 0);
this.zoomifyImage_ = context.canvas;
return context.canvas;
}
} else {
return image;
}
};
/**
* @enum {string}
*/
ol.source.Zoomify.TierSizeCalculation = {
DEFAULT: 'default',
TRUNCATED: 'truncated'
};