Imports cased like the filename
This commit is contained in:
Tim Schaub
@@ -0,0 +1,327 @@
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goog.provide('ol.reproj.Triangulation');
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goog.require('ol');
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goog.require('ol.extent');
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goog.require('ol.math');
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goog.require('ol.proj');
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/**
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* @classdesc
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* Class containing triangulation of the given target extent.
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* Used for determining source data and the reprojection itself.
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*
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* @param {ol.proj.Projection} sourceProj Source projection.
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* @param {ol.proj.Projection} targetProj Target projection.
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* @param {ol.Extent} targetExtent Target extent to triangulate.
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* @param {ol.Extent} maxSourceExtent Maximal source extent that can be used.
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* @param {number} errorThreshold Acceptable error (in source units).
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* @constructor
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*/
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ol.reproj.Triangulation = function(sourceProj, targetProj, targetExtent,
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maxSourceExtent, errorThreshold) {
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/**
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* @type {ol.proj.Projection}
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* @private
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*/
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this.sourceProj_ = sourceProj;
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/**
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* @type {ol.proj.Projection}
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* @private
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*/
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this.targetProj_ = targetProj;
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/** @type {!Object.<string, ol.Coordinate>} */
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var transformInvCache = {};
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var transformInv = ol.proj.getTransform(this.targetProj_, this.sourceProj_);
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/**
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* @param {ol.Coordinate} c A coordinate.
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* @return {ol.Coordinate} Transformed coordinate.
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* @private
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*/
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this.transformInv_ = function(c) {
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var key = c[0] + '/' + c[1];
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if (!transformInvCache[key]) {
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transformInvCache[key] = transformInv(c);
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}
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return transformInvCache[key];
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};
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/**
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* @type {ol.Extent}
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* @private
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*/
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this.maxSourceExtent_ = maxSourceExtent;
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/**
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* @type {number}
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* @private
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*/
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this.errorThresholdSquared_ = errorThreshold * errorThreshold;
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/**
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* @type {Array.<ol.ReprojTriangle>}
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* @private
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*/
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this.triangles_ = [];
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/**
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* Indicates that the triangulation crosses edge of the source projection.
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* @type {boolean}
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* @private
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*/
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this.wrapsXInSource_ = false;
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/**
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* @type {boolean}
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* @private
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*/
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this.canWrapXInSource_ = this.sourceProj_.canWrapX() &&
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!!maxSourceExtent &&
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!!this.sourceProj_.getExtent() &&
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(ol.extent.getWidth(maxSourceExtent) ==
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ol.extent.getWidth(this.sourceProj_.getExtent()));
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/**
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* @type {?number}
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* @private
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*/
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this.sourceWorldWidth_ = this.sourceProj_.getExtent() ?
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ol.extent.getWidth(this.sourceProj_.getExtent()) : null;
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/**
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* @type {?number}
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* @private
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*/
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this.targetWorldWidth_ = this.targetProj_.getExtent() ?
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ol.extent.getWidth(this.targetProj_.getExtent()) : null;
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var destinationTopLeft = ol.extent.getTopLeft(targetExtent);
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var destinationTopRight = ol.extent.getTopRight(targetExtent);
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var destinationBottomRight = ol.extent.getBottomRight(targetExtent);
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var destinationBottomLeft = ol.extent.getBottomLeft(targetExtent);
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var sourceTopLeft = this.transformInv_(destinationTopLeft);
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var sourceTopRight = this.transformInv_(destinationTopRight);
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var sourceBottomRight = this.transformInv_(destinationBottomRight);
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var sourceBottomLeft = this.transformInv_(destinationBottomLeft);
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this.addQuad_(
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destinationTopLeft, destinationTopRight,
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destinationBottomRight, destinationBottomLeft,
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sourceTopLeft, sourceTopRight, sourceBottomRight, sourceBottomLeft,
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ol.RASTER_REPROJECTION_MAX_SUBDIVISION);
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if (this.wrapsXInSource_) {
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var leftBound = Infinity;
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this.triangles_.forEach(function(triangle, i, arr) {
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leftBound = Math.min(leftBound,
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triangle.source[0][0], triangle.source[1][0], triangle.source[2][0]);
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});
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// Shift triangles to be as close to `leftBound` as possible
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// (if the distance is more than `worldWidth / 2` it can be closer.
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this.triangles_.forEach(function(triangle) {
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if (Math.max(triangle.source[0][0], triangle.source[1][0],
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triangle.source[2][0]) - leftBound > this.sourceWorldWidth_ / 2) {
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var newTriangle = [[triangle.source[0][0], triangle.source[0][1]],
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[triangle.source[1][0], triangle.source[1][1]],
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[triangle.source[2][0], triangle.source[2][1]]];
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if ((newTriangle[0][0] - leftBound) > this.sourceWorldWidth_ / 2) {
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newTriangle[0][0] -= this.sourceWorldWidth_;
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}
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if ((newTriangle[1][0] - leftBound) > this.sourceWorldWidth_ / 2) {
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newTriangle[1][0] -= this.sourceWorldWidth_;
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}
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if ((newTriangle[2][0] - leftBound) > this.sourceWorldWidth_ / 2) {
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newTriangle[2][0] -= this.sourceWorldWidth_;
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}
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// Rarely (if the extent contains both the dateline and prime meridian)
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// the shift can in turn break some triangles.
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// Detect this here and don't shift in such cases.
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var minX = Math.min(
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newTriangle[0][0], newTriangle[1][0], newTriangle[2][0]);
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var maxX = Math.max(
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newTriangle[0][0], newTriangle[1][0], newTriangle[2][0]);
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if ((maxX - minX) < this.sourceWorldWidth_ / 2) {
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triangle.source = newTriangle;
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}
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}
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}, this);
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}
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transformInvCache = {};
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};
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/**
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* Adds triangle to the triangulation.
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* @param {ol.Coordinate} a The target a coordinate.
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* @param {ol.Coordinate} b The target b coordinate.
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* @param {ol.Coordinate} c The target c coordinate.
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* @param {ol.Coordinate} aSrc The source a coordinate.
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* @param {ol.Coordinate} bSrc The source b coordinate.
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* @param {ol.Coordinate} cSrc The source c coordinate.
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* @private
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*/
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ol.reproj.Triangulation.prototype.addTriangle_ = function(a, b, c,
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aSrc, bSrc, cSrc) {
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this.triangles_.push({
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source: [aSrc, bSrc, cSrc],
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target: [a, b, c]
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});
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};
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/**
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* Adds quad (points in clock-wise order) to the triangulation
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* (and reprojects the vertices) if valid.
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* Performs quad subdivision if needed to increase precision.
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*
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* @param {ol.Coordinate} a The target a coordinate.
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* @param {ol.Coordinate} b The target b coordinate.
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* @param {ol.Coordinate} c The target c coordinate.
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* @param {ol.Coordinate} d The target d coordinate.
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* @param {ol.Coordinate} aSrc The source a coordinate.
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* @param {ol.Coordinate} bSrc The source b coordinate.
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* @param {ol.Coordinate} cSrc The source c coordinate.
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* @param {ol.Coordinate} dSrc The source d coordinate.
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* @param {number} maxSubdivision Maximal allowed subdivision of the quad.
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* @private
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*/
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ol.reproj.Triangulation.prototype.addQuad_ = function(a, b, c, d,
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aSrc, bSrc, cSrc, dSrc, maxSubdivision) {
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var sourceQuadExtent = ol.extent.boundingExtent([aSrc, bSrc, cSrc, dSrc]);
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var sourceCoverageX = this.sourceWorldWidth_ ?
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ol.extent.getWidth(sourceQuadExtent) / this.sourceWorldWidth_ : null;
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var sourceWorldWidth = /** @type {number} */ (this.sourceWorldWidth_);
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// when the quad is wrapped in the source projection
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// it covers most of the projection extent, but not fully
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var wrapsX = this.sourceProj_.canWrapX() &&
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sourceCoverageX > 0.5 && sourceCoverageX < 1;
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var needsSubdivision = false;
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if (maxSubdivision > 0) {
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if (this.targetProj_.isGlobal() && this.targetWorldWidth_) {
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var targetQuadExtent = ol.extent.boundingExtent([a, b, c, d]);
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var targetCoverageX =
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ol.extent.getWidth(targetQuadExtent) / this.targetWorldWidth_;
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needsSubdivision |=
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targetCoverageX > ol.RASTER_REPROJECTION_MAX_TRIANGLE_WIDTH;
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}
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if (!wrapsX && this.sourceProj_.isGlobal() && sourceCoverageX) {
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needsSubdivision |=
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sourceCoverageX > ol.RASTER_REPROJECTION_MAX_TRIANGLE_WIDTH;
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}
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}
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if (!needsSubdivision && this.maxSourceExtent_) {
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if (!ol.extent.intersects(sourceQuadExtent, this.maxSourceExtent_)) {
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// whole quad outside source projection extent -> ignore
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return;
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}
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}
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if (!needsSubdivision) {
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if (!isFinite(aSrc[0]) || !isFinite(aSrc[1]) ||
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!isFinite(bSrc[0]) || !isFinite(bSrc[1]) ||
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!isFinite(cSrc[0]) || !isFinite(cSrc[1]) ||
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!isFinite(dSrc[0]) || !isFinite(dSrc[1])) {
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if (maxSubdivision > 0) {
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needsSubdivision = true;
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} else {
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return;
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}
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}
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}
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if (maxSubdivision > 0) {
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if (!needsSubdivision) {
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var center = [(a[0] + c[0]) / 2, (a[1] + c[1]) / 2];
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var centerSrc = this.transformInv_(center);
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var dx;
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if (wrapsX) {
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var centerSrcEstimX =
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(ol.math.modulo(aSrc[0], sourceWorldWidth) +
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ol.math.modulo(cSrc[0], sourceWorldWidth)) / 2;
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dx = centerSrcEstimX -
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ol.math.modulo(centerSrc[0], sourceWorldWidth);
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} else {
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dx = (aSrc[0] + cSrc[0]) / 2 - centerSrc[0];
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}
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var dy = (aSrc[1] + cSrc[1]) / 2 - centerSrc[1];
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var centerSrcErrorSquared = dx * dx + dy * dy;
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needsSubdivision = centerSrcErrorSquared > this.errorThresholdSquared_;
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}
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if (needsSubdivision) {
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if (Math.abs(a[0] - c[0]) <= Math.abs(a[1] - c[1])) {
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// split horizontally (top & bottom)
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var bc = [(b[0] + c[0]) / 2, (b[1] + c[1]) / 2];
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var bcSrc = this.transformInv_(bc);
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var da = [(d[0] + a[0]) / 2, (d[1] + a[1]) / 2];
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var daSrc = this.transformInv_(da);
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this.addQuad_(
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a, b, bc, da, aSrc, bSrc, bcSrc, daSrc, maxSubdivision - 1);
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this.addQuad_(
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da, bc, c, d, daSrc, bcSrc, cSrc, dSrc, maxSubdivision - 1);
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} else {
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// split vertically (left & right)
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var ab = [(a[0] + b[0]) / 2, (a[1] + b[1]) / 2];
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var abSrc = this.transformInv_(ab);
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var cd = [(c[0] + d[0]) / 2, (c[1] + d[1]) / 2];
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var cdSrc = this.transformInv_(cd);
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this.addQuad_(
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a, ab, cd, d, aSrc, abSrc, cdSrc, dSrc, maxSubdivision - 1);
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this.addQuad_(
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ab, b, c, cd, abSrc, bSrc, cSrc, cdSrc, maxSubdivision - 1);
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}
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return;
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}
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}
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if (wrapsX) {
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if (!this.canWrapXInSource_) {
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return;
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}
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this.wrapsXInSource_ = true;
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}
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this.addTriangle_(a, c, d, aSrc, cSrc, dSrc);
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this.addTriangle_(a, b, c, aSrc, bSrc, cSrc);
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};
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/**
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* Calculates extent of the 'source' coordinates from all the triangles.
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*
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* @return {ol.Extent} Calculated extent.
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*/
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ol.reproj.Triangulation.prototype.calculateSourceExtent = function() {
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var extent = ol.extent.createEmpty();
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this.triangles_.forEach(function(triangle, i, arr) {
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var src = triangle.source;
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ol.extent.extendCoordinate(extent, src[0]);
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ol.extent.extendCoordinate(extent, src[1]);
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ol.extent.extendCoordinate(extent, src[2]);
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});
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return extent;
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};
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/**
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* @return {Array.<ol.ReprojTriangle>} Array of the calculated triangles.
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*/
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ol.reproj.Triangulation.prototype.getTriangles = function() {
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return this.triangles_;
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};
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