Java tutorial
/** * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. * * @author Arne Kepp, OpenGeo, Copyright 2009 */ package org.geowebcache.grid; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.util.Assert; public class GridSetFactory { private static Log log = LogFactory.getLog(GridSetFactory.class); /** * Default pixel size in meters, producing a default of 90.7 DPI * * @see GridSubset#getDotsPerInch() */ public static final double DEFAULT_PIXEL_SIZE_METER = 0.00028; public static int DEFAULT_LEVELS = 22; public final static double EPSG4326_TO_METERS = 6378137.0 * 2.0 * Math.PI / 360.0; public final static double EPSG3857_TO_METERS = 1; private static GridSet baseGridSet(String name, SRS srs, int tileWidth, int tileHeight) { GridSet gridSet = new GridSet(); gridSet.setName(name); gridSet.setSrs(srs); gridSet.setTileWidth(tileWidth); gridSet.setTileHeight(tileHeight); return gridSet; } /** * Note that you should provide EITHER resolutions or scales. Providing both will cause a * precondition violation exception. * * @param name * @param srs * @param extent * @param resolutions * @param scales * @param tileWidth * @param tileHeight * @param pixelSize * @param yCoordinateFirst * @return */ public static GridSet createGridSet(final String name, final SRS srs, final BoundingBox extent, boolean alignTopLeft, double[] resolutions, double[] scaleDenoms, Double metersPerUnit, double pixelSize, String[] scaleNames, int tileWidth, int tileHeight, boolean yCoordinateFirst) { Assert.notNull(name, "name is null"); Assert.notNull(srs, "srs is null"); Assert.notNull(extent, "extent is null"); Assert.isTrue(!extent.isNull() && extent.isSane(), "Extent is invalid: " + extent); Assert.isTrue(resolutions != null || scaleDenoms != null); Assert.isTrue(resolutions == null || scaleDenoms == null, "Only one of resolutions or scaleDenoms should be provided, not both"); for (int i = 1; resolutions != null && i < resolutions.length; i++) { if (resolutions[i] >= resolutions[i - 1]) { throw new IllegalArgumentException("Each resolution should be lower than it's prior one. Res[" + i + "] == " + resolutions[i] + ", Res[" + (i - 1) + "] == " + resolutions[i - 1] + "."); } } for (int i = 1; scaleDenoms != null && i < scaleDenoms.length; i++) { if (scaleDenoms[i] >= scaleDenoms[i - 1]) { throw new IllegalArgumentException( "Each scale denominator should be lower than it's prior one. Scale[" + i + "] == " + scaleDenoms[i] + ", Scale[" + (i - 1) + "] == " + scaleDenoms[i - 1] + "."); } } GridSet gridSet = baseGridSet(name, srs, tileWidth, tileHeight); gridSet.setResolutionsPreserved(resolutions != null); gridSet.setPixelSize(pixelSize); gridSet.setOriginalExtent(extent); gridSet.yBaseToggle = alignTopLeft; gridSet.setyCoordinateFirst(yCoordinateFirst); if (metersPerUnit == null) { if (srs.equals(SRS.getEPSG4326())) { gridSet.setMetersPerUnit(EPSG4326_TO_METERS); } else if (srs.equals(SRS.getEPSG3857())) { gridSet.setMetersPerUnit(EPSG3857_TO_METERS); } else { if (resolutions == null) { log.warn("GridSet " + name + " was defined without metersPerUnit, assuming 1m/unit." + " All scales will be off if this is incorrect."); } else { log.warn("GridSet " + name + " was defined without metersPerUnit. " + "Assuming 1m per SRS unit for WMTS scale output."); gridSet.setScaleWarning(true); } gridSet.setMetersPerUnit(1.0); } } else { gridSet.setMetersPerUnit(metersPerUnit); } if (resolutions == null) { gridSet.setGridLevels(new Grid[scaleDenoms.length]); } else { gridSet.setGridLevels(new Grid[resolutions.length]); } for (int i = 0; i < gridSet.getGridLevels().length; i++) { Grid curGrid = new Grid(); if (scaleDenoms != null) { curGrid.setScaleDenominator(scaleDenoms[i]); curGrid.setResolution(pixelSize * (scaleDenoms[i] / gridSet.getMetersPerUnit())); } else { curGrid.setResolution(resolutions[i]); curGrid.setScaleDenominator( (resolutions[i] * gridSet.getMetersPerUnit()) / DEFAULT_PIXEL_SIZE_METER); } final double mapUnitWidth = tileWidth * curGrid.getResolution(); final double mapUnitHeight = tileHeight * curGrid.getResolution(); final long tilesWide = (long) Math.ceil((extent.getWidth() - mapUnitWidth * 0.01) / mapUnitWidth); final long tilesHigh = (long) Math.ceil((extent.getHeight() - mapUnitHeight * 0.01) / mapUnitHeight); curGrid.setNumTilesWide(tilesWide); curGrid.setNumTilesHigh(tilesHigh); if (scaleNames == null || scaleNames[i] == null) { curGrid.setName(gridSet.getName() + ":" + i); } else { curGrid.setName(scaleNames[i]); } gridSet.getGridLevels()[i] = curGrid; } return gridSet; } public static GridSet createGridSet(final String name, final SRS srs, final BoundingBox extent, final boolean alignTopLeft, final int levels, final Double metersPerUnit, final double pixelSize, final int tileWidth, final int tileHeight, final boolean yCoordinateFirst) { final double extentWidth = extent.getWidth(); final double extentHeight = extent.getHeight(); double resX = extentWidth / tileWidth; double resY = extentHeight / tileHeight; final int tilesWide, tilesHigh; if (resX <= resY) { // use one tile wide by N tiles high tilesWide = 1; tilesHigh = (int) Math.round(resY / resX); // previous resY was assuming 1 tile high, recompute with the actual number of tiles // high resY = resY / tilesHigh; } else { // use one tile high by N tiles wide tilesHigh = 1; tilesWide = (int) Math.round(resX / resY); // previous resX was assuming 1 tile wide, recompute with the actual number of tiles // wide resX = resX / tilesWide; } // the maximum of resX and resY is the one that adjusts better final double res = Math.max(resX, resY); final double adjustedExtentWidth = tilesWide * tileWidth * res; final double adjustedExtentHeight = tilesHigh * tileHeight * res; BoundingBox adjExtent = new BoundingBox(extent); adjExtent.setMaxX(adjExtent.getMinX() + adjustedExtentWidth); // Do we keep the top or the bottom fixed? if (alignTopLeft) { adjExtent.setMinY(adjExtent.getMaxY() - adjustedExtentHeight); } else { adjExtent.setMaxY(adjExtent.getMinY() + adjustedExtentHeight); } double[] resolutions = new double[levels]; resolutions[0] = res; for (int i = 1; i < levels; i++) { resolutions[i] = resolutions[i - 1] / 2; } return createGridSet(name, srs, adjExtent, alignTopLeft, resolutions, null, metersPerUnit, pixelSize, null, tileWidth, tileHeight, yCoordinateFirst); } }