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.service.wms; import java.awt.Color; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.AffineTransform; import java.awt.image.BufferedImage; import java.awt.image.RenderedImage; import java.io.IOException; import java.util.Arrays; import java.util.Collections; import java.util.Iterator; import java.util.List; import java.util.Map; import javax.media.jai.PlanarImage; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.io.IOUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.geotools.resources.image.ImageUtilities; import org.geowebcache.GeoWebCacheException; import org.geowebcache.conveyor.Conveyor.CacheResult; import org.geowebcache.conveyor.ConveyorTile; import org.geowebcache.filter.request.RequestFilterException; import org.geowebcache.grid.BoundingBox; import org.geowebcache.grid.GridSubset; import org.geowebcache.grid.OutsideCoverageException; import org.geowebcache.grid.SRS; import org.geowebcache.io.ImageDecoderContainer; import org.geowebcache.io.ImageEncoderContainer; import org.geowebcache.io.Resource; import org.geowebcache.layer.TileLayer; import org.geowebcache.layer.TileLayerDispatcher; import org.geowebcache.layer.wms.WMSLayer; import org.geowebcache.mime.ImageMime; import org.geowebcache.mime.MimeType; import org.geowebcache.stats.RuntimeStats; import org.geowebcache.storage.StorageBroker; import org.geowebcache.util.AccountingOutputStream; import org.geowebcache.util.ServletUtils; import org.springframework.beans.BeansException; import org.springframework.context.ApplicationContext; /* * It will work as follows * 2) Based on the dimensions and bounding box of the request, GWC will determine the smallest available resolution that equals or exceeds the requested resolution. * 3) GWC will create a new in-memory raster, based on the best resolution and requested bounding box, and write the appropriate PNG tiles to it. Missing tiles will be requested from WMS. * 4) GWC will scale the raster down to the requested dimensions. * 5) GWC will then compress the raster to the desired output format and return the image. The image is not cached. */ public class WMSTileFuser { private static Log log = LogFactory.getLog(WMSTileFuser.class); private ApplicationContext applicationContext; final StorageBroker sb; final GridSubset gridSubset; final TileLayer layer; final ImageMime outputFormat; ImageMime srcFormat; int reqHeight; int reqWidth; // The desired extent of the request final BoundingBox reqBounds; // Boolean reqTransparent; // String reqBgColor; // For adjustment of final raster double xResolution; double yResolution; // The source resolution /* Follows GIS rather than Graphics conventions and so is expressed as physical size of pixel * rather than density.*/ double srcResolution; int srcIdx; // Area of tiles being used in tile coordinates long[] srcRectangle; // The spatial extent of the tiles used to fulfil the request BoundingBox srcBounds; // BoundingBox canvasBounds; /**Canvas dimensions*/ int[] canvasSize = new int[2]; static class SpatialOffsets { double top; double bottom; double left; double right; }; static class PixelOffsets { int top; int bottom; int left; int right; }; /** These are values before scaling */ PixelOffsets canvOfs = new PixelOffsets(); SpatialOffsets boundOfs = new SpatialOffsets(); /** Mosaic image*/ BufferedImage canvas; /** Graphics object used for drawing the tiles into a mosaic*/ Graphics2D gfx; /**Layer parameters*/ private Map<String, String> fullParameters; /** Map of all the possible decoders to use*/ private ImageDecoderContainer decoderMap; /** Map of all the possible encoders to use*/ private ImageEncoderContainer encoderMap; /** Hints used for writing the BufferedImage on the canvas*/ private RenderingHints hints; /** *Enum storing the Hints associated to one of the 3 configurations(SPEED, QUALITY, DEFAULT) */ public enum HintsLevel { QUALITY(0, "quality"), DEFAULT(1, "default"), SPEED(2, "speed"); private RenderingHints hints; private String mode; HintsLevel(int numHint, String mode) { this.mode = mode; switch (numHint) { // QUALITY HINTS case 0: hints = new RenderingHints(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY); hints.add(new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)); hints.add(new RenderingHints(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON)); hints.add(new RenderingHints(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY)); hints.add(new RenderingHints(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC)); hints.add(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY)); hints.add(new RenderingHints(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON)); hints.add(new RenderingHints(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_NORMALIZE)); break; // DEFAULT HINTS case 1: hints = new RenderingHints(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_DEFAULT); hints.add(new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_DEFAULT)); hints.add(new RenderingHints(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_DEFAULT)); hints.add(new RenderingHints(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_DEFAULT)); hints.add(new RenderingHints(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR)); hints.add(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_DEFAULT)); hints.add(new RenderingHints(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_DEFAULT)); hints.add( new RenderingHints(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_DEFAULT)); break; // SPEED HINTS case 2: hints = new RenderingHints(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_SPEED); hints.add(new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF)); hints.add(new RenderingHints(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_OFF)); hints.add(new RenderingHints(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_SPEED)); hints.add(new RenderingHints(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR)); hints.add(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_SPEED)); hints.add(new RenderingHints(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_OFF)); hints.add(new RenderingHints(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_PURE)); break; } } public RenderingHints getRenderingHints() { return hints; } public String getModeName() { return mode; } public static HintsLevel getHintsForMode(String mode) { if (mode != null) { if (mode.equalsIgnoreCase(QUALITY.getModeName())) { return QUALITY; } else if (mode.equalsIgnoreCase(SPEED.getModeName())) { return SPEED; } else { return DEFAULT; } } else { return DEFAULT; } } } protected WMSTileFuser(TileLayerDispatcher tld, StorageBroker sb, HttpServletRequest servReq) throws GeoWebCacheException { this.sb = sb; String[] keys = { "layers", "format", "srs", "bbox", "width", "height", "transparent", "bgcolor", "hints" }; Map<String, String> values = ServletUtils.selectedStringsFromMap(servReq.getParameterMap(), servReq.getCharacterEncoding(), keys); // TODO Parameter filters? String layerName = values.get("layers"); layer = tld.getTileLayer(layerName); gridSubset = layer.getGridSubsetForSRS(SRS.getSRS(values.get("srs"))); outputFormat = (ImageMime) ImageMime.createFromFormat(values.get("format")); List<MimeType> ml = layer.getMimeTypes(); Iterator<MimeType> iter = ml.iterator(); ImageMime firstMt = null; if (iter.hasNext()) { firstMt = (ImageMime) iter.next(); } boolean outputGif = outputFormat.getInternalName().equalsIgnoreCase("gif"); while (iter.hasNext()) { MimeType mt = iter.next(); if (outputGif) { if (mt.getInternalName().equalsIgnoreCase("gif")) { this.srcFormat = (ImageMime) mt; break; } } if (mt.getInternalName().equalsIgnoreCase("png")) { this.srcFormat = (ImageMime) mt; } } if (srcFormat == null) { srcFormat = firstMt; } reqBounds = new BoundingBox(values.get("bbox")); reqWidth = Integer.valueOf(values.get("width")); reqHeight = Integer.valueOf(values.get("height")); fullParameters = layer.getModifiableParameters(servReq.getParameterMap(), servReq.getCharacterEncoding()); if (values.get("hints") != null) { hints = HintsLevel.getHintsForMode(values.get("hints")).getRenderingHints(); } } protected WMSTileFuser(TileLayer layer, GridSubset gridSubset, BoundingBox bounds, int width, int height) { this.sb = null; this.outputFormat = ImageMime.png; this.layer = layer; this.gridSubset = gridSubset; this.reqBounds = bounds; this.reqWidth = width; this.reqHeight = height; this.fullParameters = Collections.emptyMap(); List<MimeType> ml = layer.getMimeTypes(); Iterator<MimeType> iter = ml.iterator(); ImageMime firstMt = null; if (iter.hasNext()) { firstMt = (ImageMime) iter.next(); } while (iter.hasNext()) { MimeType mt = iter.next(); if (mt.getInternalName().equalsIgnoreCase("png")) { this.srcFormat = (ImageMime) mt; break; } } if (srcFormat == null) { srcFormat = firstMt; } } protected void determineSourceResolution() { xResolution = reqBounds.getWidth() / reqWidth; yResolution = reqBounds.getHeight() / reqHeight; double tmpResolution; // We use the smallest one if (yResolution < xResolution) { tmpResolution = yResolution; } else { tmpResolution = xResolution; } log.debug("x res: " + xResolution + " y res: " + yResolution + " tmpResolution: " + tmpResolution); // Cut ourselves 0.5% slack double compResolution = 1.005 * tmpResolution; double[] resArray = gridSubset.getResolutions(); for (srcIdx = 0; srcIdx < resArray.length; srcIdx++) { srcResolution = resArray[srcIdx]; if (srcResolution < compResolution) { break; } } if (srcIdx >= resArray.length) { srcIdx = resArray.length - 1; } log.debug("z: " + srcIdx + " , resolution: " + srcResolution + " (" + tmpResolution + ")"); // At worst, we have the best resolution possible } protected void determineCanvasLayout() { // Find the spatial extent of the tiles needed to cover the desired extent srcRectangle = gridSubset.getCoverageIntersection(srcIdx, reqBounds); srcBounds = gridSubset.boundsFromRectangle(srcRectangle); // We now have the complete area, lets figure out our offsets // Positive means that there is blank space to the first tile, // negative means we will not use the entire tile boundOfs.left = srcBounds.getMinX() - reqBounds.getMinX(); boundOfs.bottom = srcBounds.getMinY() - reqBounds.getMinY(); boundOfs.right = reqBounds.getMaxX() - srcBounds.getMaxX(); boundOfs.top = reqBounds.getMaxY() - srcBounds.getMaxY(); canvasSize[0] = (int) Math.round(reqBounds.getWidth() / this.srcResolution); canvasSize[1] = (int) Math.round(reqBounds.getHeight() / this.srcResolution); PixelOffsets naiveOfs = new PixelOffsets(); // Calculate the corresponding pixel offsets. We'll stick to sane, // i.e. bottom left, coordinates at this point naiveOfs.left = (int) Math.round(boundOfs.left / this.srcResolution); naiveOfs.bottom = (int) Math.round(boundOfs.bottom / this.srcResolution); naiveOfs.right = (int) Math.round(boundOfs.right / this.srcResolution); naiveOfs.top = (int) Math.round(boundOfs.top / this.srcResolution); // Find the offsets on the opposite sides. This is dependent of how the first two were rounded. // First, find a tile boundary near the canvas edge, then make sure it's on the correct // side to match the corresponding boundOfs, then take the modulo of the naive rounding // based on the boundOfs, then subtract the two and apply the difference to the boundOfs. int tileWidth = this.gridSubset.getTileWidth(); int tileHeight = this.gridSubset.getTileHeight(); canvOfs.left = naiveOfs.left; canvOfs.bottom = naiveOfs.bottom; canvOfs.right = (canvasSize[0] - canvOfs.left) % tileWidth; // Find nearby tile boundary canvOfs.right = (Integer.signum(naiveOfs.right) * tileWidth + canvOfs.right) % tileWidth; // Ensure same sign as naive calculation canvOfs.right = canvOfs.right - (naiveOfs.right % tileWidth) + naiveOfs.right; // Find adjustment from naive and apply to naive calculation canvOfs.top = (canvasSize[1] - canvOfs.bottom) % tileHeight; // Find nearby tile boundary canvOfs.top = (Integer.signum(naiveOfs.top) * tileHeight + canvOfs.top) % tileHeight; // Ensure same sign as naive calculation canvOfs.top = canvOfs.top - (naiveOfs.top % tileHeight) + naiveOfs.top; // Find adjustment from naive and apply to naive calculation //postconditions assert Math.abs(canvOfs.left - naiveOfs.left) <= 1; assert Math.abs(canvOfs.bottom - naiveOfs.bottom) <= 1; assert Math.abs(canvOfs.right - naiveOfs.right) <= 1; assert Math.abs(canvOfs.top - naiveOfs.top) <= 1; if (log.isDebugEnabled()) { log.debug("intersection rectangle: " + Arrays.toString(srcRectangle)); log.debug("intersection bounds: " + srcBounds + " (" + reqBounds + ")"); log.debug("Bound offsets: " + Arrays .toString(new double[] { boundOfs.left, boundOfs.bottom, boundOfs.right, boundOfs.top })); log.debug("Canvas size: " + Arrays.toString(canvasSize) + "(" + reqWidth + "," + reqHeight + ")"); log.debug("Canvas offsets: " + Arrays.toString(new int[] { canvOfs.left, canvOfs.bottom, canvOfs.right, canvOfs.top })); } } protected void createCanvas() { // TODO take bgcolor and transparency from request into account // should move this into a separate function Color bgColor = null; boolean transparent = true; if (layer instanceof WMSLayer) { WMSLayer wmsLayer = (WMSLayer) layer; int[] colorAr = wmsLayer.getBackgroundColor(); if (colorAr != null) { bgColor = new Color(colorAr[0], colorAr[1], colorAr[2]); } transparent = wmsLayer.getTransparent(); } int canvasType; if (bgColor == null && transparent && (outputFormat.supportsAlphaBit() || outputFormat.supportsAlphaChannel())) { canvasType = BufferedImage.TYPE_INT_ARGB; } else { canvasType = BufferedImage.TYPE_INT_RGB; if (bgColor == null) { bgColor = Color.WHITE; } } // Create the actual canvas and graphics object canvas = new BufferedImage(canvasSize[0], canvasSize[1], canvasType); gfx = (Graphics2D) canvas.getGraphics(); if (bgColor != null) { gfx.setColor(bgColor); gfx.fillRect(0, 0, canvasSize[0], canvasSize[1]); } // Hints settings RenderingHints hintsTemp = HintsLevel.DEFAULT.getRenderingHints(); if (hints != null) { hintsTemp = hints; } gfx.addRenderingHints(hintsTemp); } protected void renderCanvas() throws OutsideCoverageException, GeoWebCacheException, IOException, Exception { // Now we loop over all the relevant tiles and write them to the canvas, // Starting at the bottom, moving to the right and up // Bottom row of tiles, in tile coordinates long starty = srcRectangle[1]; // gridy is the tile row index for (long gridy = starty; gridy <= srcRectangle[3]; gridy++) { int tiley = 0; int canvasy = (int) (srcRectangle[3] - gridy) * gridSubset.getTileHeight(); int tileHeight = gridSubset.getTileHeight(); if (canvOfs.top > 0) { // Add padding canvasy += canvOfs.top; } else { // Top tile is cut off if (gridy == srcRectangle[3]) { // This one starts at the top, so canvasy remains 0 tileHeight = tileHeight + canvOfs.top; tiley = -canvOfs.top; } else { // Offset that the first tile contributed, // rather, we subtract what it did not contribute canvasy += canvOfs.top; } } if (gridy == srcRectangle[1] && canvOfs.bottom < 0) { // Check whether we only use part of the first tiles (bottom row) // Offset is negative, slice the bottom off the tile tileHeight += canvOfs.bottom; } long startx = srcRectangle[0]; for (long gridx = startx; gridx <= srcRectangle[2]; gridx++) { long[] gridLoc = { gridx, gridy, srcIdx }; ConveyorTile tile = new ConveyorTile(sb, layer.getName(), gridSubset.getName(), gridLoc, srcFormat, fullParameters, null, null); // Check whether this tile is to be rendered at all try { layer.applyRequestFilters(tile); } catch (RequestFilterException e) { log.debug(e.getMessage(), e); continue; } layer.getTile(tile); // Selection of the resource input stream Resource blob = tile.getBlob(); // Extraction of the image associated with the defined MimeType String formatName = srcFormat.getMimeType(); BufferedImage tileImg = decoderMap.decode(formatName, blob, decoderMap.isAggressiveInputStreamSupported(formatName), null); int tilex = 0; int canvasx = (int) (gridx - startx) * gridSubset.getTileWidth(); int tileWidth = gridSubset.getTileWidth(); if (canvOfs.left > 0) { // Add padding canvasx += canvOfs.left; } else { // Leftmost tile is cut off if (gridx == srcRectangle[0]) { // This one starts to the left top, so canvasx remains 0 tileWidth = tileWidth + canvOfs.left; tilex = -canvOfs.left; } else { // Offset that the first tile contributed, // rather, we subtract what it did not contribute canvasx += canvOfs.left; } } if (gridx == srcRectangle[2] && canvOfs.right < 0) { // Check whether we only use part of the first tiles (bottom row) // Offset is negative, slice the bottom off the tile tileWidth = tileWidth + canvOfs.right; } // TODO We should really ensure we can never get here if (tileWidth == 0 || tileHeight == 0) { log.debug("tileWidth: " + tileWidth + " tileHeight: " + tileHeight); continue; } // Cut down the tile to the part we want if (tileWidth != gridSubset.getTileWidth() || tileHeight != gridSubset.getTileHeight()) { log.debug("tileImg.getSubimage(" + tilex + "," + tiley + "," + tileWidth + "," + tileHeight + ")"); tileImg = tileImg.getSubimage(tilex, tiley, tileWidth, tileHeight); } // Render the tile on the big canvas log.debug("drawImage(subtile," + canvasx + "," + canvasy + ",null) " + Arrays.toString(gridLoc)); gfx.drawImage(tileImg, canvasx, canvasy, null); // imageObserver } } gfx.dispose(); } protected void scaleRaster() { if (canvasSize[0] != reqWidth || canvasSize[1] != reqHeight) { BufferedImage preTransform = canvas; canvas = new BufferedImage(reqWidth, reqHeight, preTransform.getType()); Graphics2D gfx = canvas.createGraphics(); AffineTransform affineTrans = AffineTransform.getScaleInstance( ((double) reqWidth) / preTransform.getWidth(), ((double) reqHeight) / preTransform.getHeight()); log.debug("AffineTransform: " + (((double) reqWidth) / preTransform.getWidth()) + "," + +(((double) reqHeight) / preTransform.getHeight())); // Hints settings RenderingHints hintsTemp = HintsLevel.DEFAULT.getRenderingHints(); if (hints != null) { hintsTemp = hints; } gfx.addRenderingHints(hintsTemp); gfx.drawRenderedImage(preTransform, affineTrans); gfx.dispose(); } } protected void writeResponse(HttpServletResponse response, RuntimeStats stats) throws IOException, OutsideCoverageException, GeoWebCacheException, Exception { determineSourceResolution(); determineCanvasLayout(); createCanvas(); renderCanvas(); scaleRaster(); AccountingOutputStream aos = null; RenderedImage finalImage = null; try { finalImage = canvas; response.setStatus(HttpServletResponse.SC_OK); response.setContentType(this.outputFormat.getMimeType()); response.setCharacterEncoding("UTF-8"); ServletOutputStream os = response.getOutputStream(); aos = new AccountingOutputStream(os); // Image encoding with the associated writer encoderMap.encode(finalImage, outputFormat, aos, encoderMap.isAggressiveOutputStreamSupported(outputFormat.getMimeType()), null); log.debug("WMS response size: " + aos.getCount() + "bytes."); stats.log(aos.getCount(), CacheResult.WMS); } catch (Exception e) { log.debug("IOException writing untiled response to client: " + e.getMessage(), e); // closing the stream if (aos != null) { IOUtils.closeQuietly(aos); } // releasing Image if (finalImage != null) { ImageUtilities.disposePlanarImageChain(PlanarImage.wrapRenderedImage(finalImage)); } } } /** * Setting of the ApplicationContext associated for extracting the related beans * * @param context * @throws BeansException */ public void setApplicationContext(ApplicationContext context) throws BeansException { applicationContext = context; decoderMap = applicationContext.getBean(ImageDecoderContainer.class); encoderMap = applicationContext.getBean(ImageEncoderContainer.class); } /** * Setting of the hints configuration taken from the WMSService * @param hintsConfig */ public void setHintsConfiguration(String hintsConfig) { if (hints == null) { hints = HintsLevel.getHintsForMode(hintsConfig).getRenderingHints(); } } }