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   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
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   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

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package org.apache.batik.ext.awt.image.rendered;

import  java.awt.image.Raster;

import org.apache.batik.util.HaltingThread;

This is a Grid based implementation of the TileStore. This makes it pretty quick, but it can use a fair amount of memory for large tile grids.
Version:$Id: TileGrid.java 1733416 2016-03-03 07:07:13Z gadams $
/** * This is a Grid based implementation of the TileStore. * This makes it pretty quick, but it can use a fair amount of * memory for large tile grids. * * @version $Id: TileGrid.java 1733416 2016-03-03 07:07:13Z gadams $ */
public class TileGrid implements TileStore { private static final boolean DEBUG = false; private static final boolean COUNT = false; private int xSz, ySz; private int minTileX, minTileY; private TileLRUMember [][] rasters=null; private TileGenerator source = null; private LRUCache cache = null; public TileGrid(int minTileX, int minTileY, int xSz, int ySz, TileGenerator source, LRUCache cache) { this.cache = cache; this.source = source; this.minTileX = minTileX; this.minTileY = minTileY; this.xSz = xSz; this.ySz = ySz; rasters = new TileLRUMember[ySz][]; } public void setTile(int x, int y, Raster ras) { x-= minTileX; y-= minTileY; if ((x<0) || (x>=xSz)) return; if ((y<0) || (y>=ySz)) return; TileLRUMember [] row = rasters[y]; TileLRUMember item; if (ras == null) { // Clearing entry. if (row == null) return; item = row[x]; if (item == null) return; row[x] = null; cache.remove(item); return; } if (row != null) { item = row[x]; if (item == null) { item = new TileLRUMember(); row[x] = item; } } else { row = new TileLRUMember[xSz]; item = new TileLRUMember(); row[x] = item; rasters[y] = row; } item.setRaster(ras); cache.add(item); if (DEBUG) System.out.println("Setting: (" + (x+minTileX) + ", " + (y+minTileY) + ")"); } // Returns Raster if the tile is _currently_ in the cache. // If it is not currently in the cache it returns null. public Raster getTileNoCompute(int x, int y) { x-=minTileX; y-=minTileY; if ((x<0) || (x>=xSz)) return null; if ((y<0) || (y>=ySz)) return null; TileLRUMember [] row = rasters[y]; if (row == null) return null; TileLRUMember item = row[x]; if (item == null) return null; Raster ret = item.retrieveRaster(); if (ret != null) cache.add(item); return ret; } public Raster getTile(int x, int y) { x-=minTileX; y-=minTileY; if ((x<0) || (x>=xSz)) return null; if ((y<0) || (y>=ySz)) return null; if (DEBUG) System.out.println("Fetching: (" + (x+minTileX) + ", " + (y+minTileY) + ")"); if (COUNT) synchronized (TileGrid.class) { requests++; } Raster ras = null; TileLRUMember [] row = rasters[y]; TileLRUMember item = null; if (row != null) { item = row[x]; if (item != null) ras = item.retrieveRaster(); else { item = new TileLRUMember(); row[x] = item; } } else { row = new TileLRUMember[xSz]; rasters[y] = row; item = new TileLRUMember(); row[x] = item; } if (ras == null) { if (DEBUG) System.out.println("Generating: ("+(x+minTileX)+", "+ (y+minTileY) + ")"); if (COUNT) synchronized (TileGrid.class) { misses++; } ras = source.genTile(x+minTileX, y+minTileY); // In all likelyhood the contents of this tile is junk! // So don't cache it (returning is probably fine since it // won't come back to haunt us... if (HaltingThread.hasBeenHalted()) return ras; item.setRaster(ras); } // Update the item's position in the cache.. cache.add(item); return ras; } static int requests; static int misses; }