Files
openlayers/src/ol/source/rastersource.js
2015-07-21 17:12:06 -06:00

375 lines
9.8 KiB
JavaScript

goog.provide('ol.source.Raster');
goog.provide('ol.source.RasterEvent');
goog.provide('ol.source.RasterEventType');
goog.require('goog.asserts');
goog.require('goog.events.Event');
goog.require('goog.functions');
goog.require('goog.vec.Mat4');
goog.require('ol.ImageCanvas');
goog.require('ol.TileQueue');
goog.require('ol.dom');
goog.require('ol.extent');
goog.require('ol.layer.Image');
goog.require('ol.layer.Tile');
goog.require('ol.raster.IdentityOp');
goog.require('ol.renderer.canvas.ImageLayer');
goog.require('ol.renderer.canvas.TileLayer');
goog.require('ol.source.Image');
goog.require('ol.source.Tile');
/**
* @classdesc
* An source that transforms data from any number of input sources source using
* an array of {@link ol.raster.Operation} functions to transform input pixel
* values into output pixel values.
*
* @constructor
* @extends {ol.source.Image}
* @param {olx.source.RasterOptions} options Options.
* @api
*/
ol.source.Raster = function(options) {
/**
* @private
* @type {Array.<ol.raster.Operation>}
*/
this.operations_ = goog.isDef(options.operations) ?
options.operations : [ol.raster.IdentityOp];
/**
* @private
* @type {Array.<ol.renderer.canvas.Layer>}
*/
this.renderers_ = ol.source.Raster.createRenderers_(options.sources);
/**
* @private
* @type {CanvasRenderingContext2D}
*/
this.canvasContext_ = ol.dom.createCanvasContext2D();
/**
* @private
* @type {ol.TileQueue}
*/
this.tileQueue_ = new ol.TileQueue(
goog.functions.constant(1),
goog.bind(this.changed, this));
var layerStatesArray = ol.source.Raster.getLayerStatesArray_(this.renderers_);
var layerStates = {};
for (var i = 0, ii = layerStatesArray.length; i < ii; ++i) {
layerStates[goog.getUid(layerStatesArray[i].layer)] = layerStatesArray[i];
}
/**
* @private
* @type {olx.FrameState}
*/
this.frameState_ = {
animate: false,
attributions: {},
coordinateToPixelMatrix: goog.vec.Mat4.createNumber(),
extent: null,
focus: null,
index: 0,
layerStates: layerStates,
layerStatesArray: layerStatesArray,
logos: {},
pixelRatio: 1,
pixelToCoordinateMatrix: goog.vec.Mat4.createNumber(),
postRenderFunctions: [],
size: [0, 0],
skippedFeatureUids: {},
tileQueue: this.tileQueue_,
time: Date.now(),
usedTiles: {},
viewState: /** @type {olx.ViewState} */ ({
rotation: 0
}),
viewHints: [],
wantedTiles: {}
};
goog.base(this, {
// TODO: pass along any relevant options
});
};
goog.inherits(ol.source.Raster, ol.source.Image);
/**
* Update the stored frame state.
* @param {ol.Extent} extent The view extent (in map units).
* @param {number} resolution The view resolution.
* @param {ol.proj.Projection} projection The view projection.
* @return {olx.FrameState} The updated frame state.
* @private
*/
ol.source.Raster.prototype.updateFrameState_ =
function(extent, resolution, projection) {
var frameState = this.frameState_;
var center = ol.extent.getCenter(extent);
var width = ol.extent.getWidth(extent) / resolution;
var height = ol.extent.getHeight(extent) / resolution;
frameState.extent = extent;
frameState.focus = ol.extent.getCenter(extent);
frameState.size[0] = width;
frameState.size[1] = height;
var viewState = frameState.viewState;
viewState.center = center;
viewState.projection = projection;
viewState.resolution = resolution;
return frameState;
};
/**
* @inheritDoc
*/
ol.source.Raster.prototype.getImage =
function(extent, resolution, pixelRatio, projection) {
var context = this.canvasContext_;
var canvas = context.canvas;
var width = ol.extent.getWidth(extent) / resolution;
var height = ol.extent.getHeight(extent) / resolution;
if (width !== canvas.width ||
height !== canvas.height) {
canvas.width = width;
canvas.height = height;
}
var frameState = this.updateFrameState_(extent, resolution, projection);
this.composeFrame_(frameState);
var imageCanvas = new ol.ImageCanvas(extent, resolution, 1,
this.getAttributions(), canvas);
return imageCanvas;
};
/**
* Compose the frame. This renders data from all sources, runs pixel-wise
* operations, and renders the result to the stored canvas context.
* @param {olx.FrameState} frameState The frame state.
* @private
*/
ol.source.Raster.prototype.composeFrame_ = function(frameState) {
var len = this.renderers_.length;
var imageDatas = new Array(len);
var pixels = new Array(len);
var context = this.canvasContext_;
var canvas = context.canvas;
for (var i = 0; i < len; ++i) {
pixels[i] = [0, 0, 0, 0];
imageDatas[i] = ol.source.Raster.getImageData_(
this.renderers_[i], canvas.width, canvas.height,
frameState, frameState.layerStatesArray[i]);
}
var targetImageData = context.getImageData(0, 0, canvas.width, canvas.height);
var target = targetImageData.data;
var resolution = frameState.viewState.resolution / frameState.pixelRatio;
this.dispatchEvent(new ol.source.RasterEvent(
ol.source.RasterEventType.BEFOREOPERATIONS, resolution));
var source, pixel;
for (var j = 0, jj = target.length; j < jj; j += 4) {
for (var k = 0; k < len; ++k) {
source = imageDatas[k].data;
pixel = pixels[k];
pixel[0] = source[j];
pixel[1] = source[j + 1];
pixel[2] = source[j + 2];
pixel[3] = source[j + 3];
}
this.runOperations_(pixels);
pixel = pixels[0];
target[j] = pixel[0];
target[j + 1] = pixel[1];
target[j + 2] = pixel[2];
target[j + 3] = pixel[3];
}
this.dispatchEvent(new ol.source.RasterEvent(
ol.source.RasterEventType.AFTEROPERATIONS, resolution));
context.putImageData(targetImageData, 0, 0);
frameState.tileQueue.loadMoreTiles(16, 16);
};
/**
* Run pixel-wise operations to transform pixels.
* @param {Array.<ol.raster.Pixel>} pixels The input pixels.
* @return {Array.<ol.raster.Pixel>} The modified pixels.
* @private
*/
ol.source.Raster.prototype.runOperations_ = function(pixels) {
for (var i = 0, ii = this.operations_.length; i < ii; ++i) {
pixels = this.operations_[i](pixels);
}
return pixels;
};
/**
* Get image data from a renderer.
* @param {ol.renderer.canvas.Layer} renderer Layer renderer.
* @param {number} width Data width.
* @param {number} height Data height.
* @param {olx.FrameState} frameState The frame state.
* @param {ol.layer.LayerState} layerState The layer state.
* @return {ImageData} The image data.
* @private
*/
ol.source.Raster.getImageData_ =
function(renderer, width, height, frameState, layerState) {
renderer.prepareFrame(frameState, layerState);
var canvas = renderer.getImage();
var imageTransform = renderer.getImageTransform();
var dx = goog.vec.Mat4.getElement(imageTransform, 0, 3);
var dy = goog.vec.Mat4.getElement(imageTransform, 1, 3);
return canvas.getContext('2d').getImageData(
Math.round(-dx), Math.round(-dy),
width, height);
};
/**
* Get a list of layer states from a list of renderers.
* @param {Array.<ol.renderer.canvas.Layer>} renderers Layer renderers.
* @return {Array.<ol.layer.LayerState>} The layer states.
* @private
*/
ol.source.Raster.getLayerStatesArray_ = function(renderers) {
return renderers.map(function(renderer) {
return renderer.getLayer().getLayerState();
});
};
/**
* Create renderers for all sources.
* @param {Array.<ol.source.Source>} sources The sources.
* @return {Array.<ol.renderer.canvas.Layer>} Array of layer renderers.
* @private
*/
ol.source.Raster.createRenderers_ = function(sources) {
var len = sources.length;
var renderers = new Array(len);
for (var i = 0; i < len; ++i) {
renderers[i] = ol.source.Raster.createRenderer_(sources[i]);
}
return renderers;
};
/**
* Create a renderer for the provided source.
* @param {ol.source.Source} source The source.
* @return {ol.renderer.canvas.Layer} The renderer.
* @private
*/
ol.source.Raster.createRenderer_ = function(source) {
var renderer = null;
if (source instanceof ol.source.Tile) {
renderer = ol.source.Raster.createTileRenderer_(
/** @type {ol.source.Tile} */ (source));
} else if (source instanceof ol.source.Image) {
renderer = ol.source.Raster.createImageRenderer_(
/** @type {ol.source.Image} */ (source));
} else {
goog.asserts.fail('Unsupported source type: ' + source);
}
return renderer;
};
/**
* Create an image renderer for the provided source.
* @param {ol.source.Image} source The source.
* @return {ol.renderer.canvas.Layer} The renderer.
* @private
*/
ol.source.Raster.createImageRenderer_ = function(source) {
var layer = new ol.layer.Image({source: source});
return new ol.renderer.canvas.ImageLayer(layer);
};
/**
* Create a tile renderer for the provided source.
* @param {ol.source.Tile} source The source.
* @return {ol.renderer.canvas.Layer} The renderer.
* @private
*/
ol.source.Raster.createTileRenderer_ = function(source) {
var layer = new ol.layer.Tile({source: source});
return new ol.renderer.canvas.TileLayer(layer);
};
/**
* @classdesc
* Events emitted by {@link ol.source.Raster} instances are instances of this
* type.
*
* @constructor
* @extends {goog.events.Event}
* @implements {oli.source.RasterEvent}
* @param {string} type Type.
* @param {number} resolution Map units per pixel.
*/
ol.source.RasterEvent = function(type, resolution) {
goog.base(this, type);
/**
* Map units per pixel.
* @type {number}
* @api
*/
this.resolution = resolution;
};
goog.inherits(ol.source.RasterEvent, goog.events.Event);
/**
* @enum {string}
*/
ol.source.RasterEventType = {
/**
* Triggered before operations are run.
* @event ol.source.RasterEvent#beforeoperations
* @api
*/
BEFOREOPERATIONS: 'beforeoperations',
/**
* Triggered after operations are run.
* @event ol.source.RasterEvent#afteroperations
* @api
*/
AFTEROPERATIONS: 'afteroperations'
};