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| goog.provide('ol.renderer.webgl.ImageLayer');
goog.require('ol');
goog.require('ol.LayerType');
goog.require('ol.ViewHint');
goog.require('ol.dom');
goog.require('ol.extent');
goog.require('ol.functions');
goog.require('ol.renderer.Type');
goog.require('ol.renderer.webgl.Layer');
goog.require('ol.source.ImageVector');
goog.require('ol.transform');
goog.require('ol.webgl');
goog.require('ol.webgl.Context');
/**
* @constructor
* @extends {ol.renderer.webgl.Layer}
* @param {ol.renderer.webgl.Map} mapRenderer Map renderer.
* @param {ol.layer.Image} imageLayer Tile layer.
* @api
*/
ol.renderer.webgl.ImageLayer = function(mapRenderer, imageLayer) {
ol.renderer.webgl.Layer.call(this, mapRenderer, imageLayer);
/**
* The last rendered image.
* @private
* @type {?ol.ImageBase}
*/
this.image_ = null;
/**
* @private
* @type {CanvasRenderingContext2D}
*/
this.hitCanvasContext_ = null;
/**
* @private
* @type {?ol.Transform}
*/
this.hitTransformationMatrix_ = null;
};
ol.inherits(ol.renderer.webgl.ImageLayer, ol.renderer.webgl.Layer);
/**
* Determine if this renderer handles the provided layer.
* @param {ol.renderer.Type} type The renderer type.
* @param {ol.layer.Layer} layer The candidate layer.
* @return {boolean} The renderer can render the layer.
*/
ol.renderer.webgl.ImageLayer['handles'] = function(type, layer) {
return type === ol.renderer.Type.WEBGL && layer.getType() === ol.LayerType.IMAGE;
};
/**
* Create a layer renderer.
* @param {ol.renderer.Map} mapRenderer The map renderer.
* @param {ol.layer.Layer} layer The layer to be rendererd.
* @return {ol.renderer.webgl.ImageLayer} The layer renderer.
*/
ol.renderer.webgl.ImageLayer['create'] = function(mapRenderer, layer) {
return new ol.renderer.webgl.ImageLayer(
/** @type {ol.renderer.webgl.Map} */ (mapRenderer),
/** @type {ol.layer.Image} */ (layer)
);
};
/**
* @param {ol.ImageBase} image Image.
* @private
* @return {WebGLTexture} Texture.
*/
ol.renderer.webgl.ImageLayer.prototype.createTexture_ = function(image) {
// We meet the conditions to work with non-power of two textures.
// http://www.khronos.org/webgl/wiki/WebGL_and_OpenGL_Differences#Non-Power_of_Two_Texture_Support
// http://learningwebgl.com/blog/?p=2101
var imageElement = image.getImage();
var gl = this.mapRenderer.getGL();
return ol.webgl.Context.createTexture(
gl, imageElement, ol.webgl.CLAMP_TO_EDGE, ol.webgl.CLAMP_TO_EDGE);
};
/**
* @inheritDoc
*/
ol.renderer.webgl.ImageLayer.prototype.forEachFeatureAtCoordinate = function(coordinate, frameState, hitTolerance, callback, thisArg) {
var layer = this.getLayer();
var source = layer.getSource();
var resolution = frameState.viewState.resolution;
var rotation = frameState.viewState.rotation;
var skippedFeatureUids = frameState.skippedFeatureUids;
return source.forEachFeatureAtCoordinate(
coordinate, resolution, rotation, hitTolerance, skippedFeatureUids,
/**
* @param {ol.Feature|ol.render.Feature} feature Feature.
* @return {?} Callback result.
*/
function(feature) {
return callback.call(thisArg, feature, layer);
});
};
/**
* @inheritDoc
*/
ol.renderer.webgl.ImageLayer.prototype.prepareFrame = function(frameState, layerState, context) {
var gl = this.mapRenderer.getGL();
var pixelRatio = frameState.pixelRatio;
var viewState = frameState.viewState;
var viewCenter = viewState.center;
var viewResolution = viewState.resolution;
var viewRotation = viewState.rotation;
var image = this.image_;
var texture = this.texture;
var imageLayer = /** @type {ol.layer.Image} */ (this.getLayer());
var imageSource = imageLayer.getSource();
var hints = frameState.viewHints;
var renderedExtent = frameState.extent;
if (layerState.extent !== undefined) {
renderedExtent = ol.extent.getIntersection(
renderedExtent, layerState.extent);
}
if (!hints[ol.ViewHint.ANIMATING] && !hints[ol.ViewHint.INTERACTING] &&
!ol.extent.isEmpty(renderedExtent)) {
var projection = viewState.projection;
if (!ol.ENABLE_RASTER_REPROJECTION) {
var sourceProjection = imageSource.getProjection();
if (sourceProjection) {
projection = sourceProjection;
}
}
var image_ = imageSource.getImage(renderedExtent, viewResolution,
pixelRatio, projection);
if (image_) {
var loaded = this.loadImage(image_);
if (loaded) {
image = image_;
texture = this.createTexture_(image_);
if (this.texture) {
/**
* @param {WebGLRenderingContext} gl GL.
* @param {WebGLTexture} texture Texture.
*/
var postRenderFunction = function(gl, texture) {
if (!gl.isContextLost()) {
gl.deleteTexture(texture);
}
}.bind(null, gl, this.texture);
frameState.postRenderFunctions.push(
/** @type {ol.PostRenderFunction} */ (postRenderFunction)
);
}
}
}
}
if (image) {
var canvas = this.mapRenderer.getContext().getCanvas();
this.updateProjectionMatrix_(canvas.width, canvas.height,
pixelRatio, viewCenter, viewResolution, viewRotation,
image.getExtent());
this.hitTransformationMatrix_ = null;
// Translate and scale to flip the Y coord.
var texCoordMatrix = this.texCoordMatrix;
ol.transform.reset(texCoordMatrix);
ol.transform.scale(texCoordMatrix, 1, -1);
ol.transform.translate(texCoordMatrix, 0, -1);
this.image_ = image;
this.texture = texture;
this.updateAttributions(frameState.attributions, image.getAttributions());
this.updateLogos(frameState, imageSource);
}
return !!image;
};
/**
* @param {number} canvasWidth Canvas width.
* @param {number} canvasHeight Canvas height.
* @param {number} pixelRatio Pixel ratio.
* @param {ol.Coordinate} viewCenter View center.
* @param {number} viewResolution View resolution.
* @param {number} viewRotation View rotation.
* @param {ol.Extent} imageExtent Image extent.
* @private
*/
ol.renderer.webgl.ImageLayer.prototype.updateProjectionMatrix_ = function(canvasWidth, canvasHeight, pixelRatio,
viewCenter, viewResolution, viewRotation, imageExtent) {
var canvasExtentWidth = canvasWidth * viewResolution;
var canvasExtentHeight = canvasHeight * viewResolution;
var projectionMatrix = this.projectionMatrix;
ol.transform.reset(projectionMatrix);
ol.transform.scale(projectionMatrix,
pixelRatio * 2 / canvasExtentWidth,
pixelRatio * 2 / canvasExtentHeight);
ol.transform.rotate(projectionMatrix, -viewRotation);
ol.transform.translate(projectionMatrix,
imageExtent[0] - viewCenter[0],
imageExtent[1] - viewCenter[1]);
ol.transform.scale(projectionMatrix,
(imageExtent[2] - imageExtent[0]) / 2,
(imageExtent[3] - imageExtent[1]) / 2);
ol.transform.translate(projectionMatrix, 1, 1);
};
/**
* @inheritDoc
*/
ol.renderer.webgl.ImageLayer.prototype.hasFeatureAtCoordinate = function(coordinate, frameState) {
var hasFeature = this.forEachFeatureAtCoordinate(
coordinate, frameState, 0, ol.functions.TRUE, this);
return hasFeature !== undefined;
};
/**
* @inheritDoc
*/
ol.renderer.webgl.ImageLayer.prototype.forEachLayerAtPixel = function(pixel, frameState, callback, thisArg) {
if (!this.image_ || !this.image_.getImage()) {
return undefined;
}
if (this.getLayer().getSource() instanceof ol.source.ImageVector) {
// for ImageVector sources use the original hit-detection logic,
// so that for example also transparent polygons are detected
var coordinate = ol.transform.apply(
frameState.pixelToCoordinateTransform, pixel.slice());
var hasFeature = this.forEachFeatureAtCoordinate(
coordinate, frameState, 0, ol.functions.TRUE, this);
if (hasFeature) {
return callback.call(thisArg, this.getLayer(), null);
} else {
return undefined;
}
} else {
var imageSize =
[this.image_.getImage().width, this.image_.getImage().height];
if (!this.hitTransformationMatrix_) {
this.hitTransformationMatrix_ = this.getHitTransformationMatrix_(
frameState.size, imageSize);
}
var pixelOnFrameBuffer = ol.transform.apply(
this.hitTransformationMatrix_, pixel.slice());
if (pixelOnFrameBuffer[0] < 0 || pixelOnFrameBuffer[0] > imageSize[0] ||
pixelOnFrameBuffer[1] < 0 || pixelOnFrameBuffer[1] > imageSize[1]) {
// outside the image, no need to check
return undefined;
}
if (!this.hitCanvasContext_) {
this.hitCanvasContext_ = ol.dom.createCanvasContext2D(1, 1);
}
this.hitCanvasContext_.clearRect(0, 0, 1, 1);
this.hitCanvasContext_.drawImage(this.image_.getImage(),
pixelOnFrameBuffer[0], pixelOnFrameBuffer[1], 1, 1, 0, 0, 1, 1);
var imageData = this.hitCanvasContext_.getImageData(0, 0, 1, 1).data;
if (imageData[3] > 0) {
return callback.call(thisArg, this.getLayer(), imageData);
} else {
return undefined;
}
}
};
/**
* The transformation matrix to get the pixel on the image for a
* pixel on the map.
* @param {ol.Size} mapSize The map size.
* @param {ol.Size} imageSize The image size.
* @return {ol.Transform} The transformation matrix.
* @private
*/
ol.renderer.webgl.ImageLayer.prototype.getHitTransformationMatrix_ = function(mapSize, imageSize) {
// the first matrix takes a map pixel, flips the y-axis and scales to
// a range between -1 ... 1
var mapCoordTransform = ol.transform.create();
ol.transform.translate(mapCoordTransform, -1, -1);
ol.transform.scale(mapCoordTransform, 2 / mapSize[0], 2 / mapSize[1]);
ol.transform.translate(mapCoordTransform, 0, mapSize[1]);
ol.transform.scale(mapCoordTransform, 1, -1);
// the second matrix is the inverse of the projection matrix used in the
// shader for drawing
var projectionMatrixInv = ol.transform.invert(this.projectionMatrix.slice());
// the third matrix scales to the image dimensions and flips the y-axis again
var transform = ol.transform.create();
ol.transform.translate(transform, 0, imageSize[1]);
ol.transform.scale(transform, 1, -1);
ol.transform.scale(transform, imageSize[0] / 2, imageSize[1] / 2);
ol.transform.translate(transform, 1, 1);
ol.transform.multiply(transform, projectionMatrixInv);
ol.transform.multiply(transform, mapCoordTransform);
return transform;
};
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