Application: gvSIG desktop » gvSIG raster

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * 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 General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 */

package org.gvsig.raster.impl.provider.tile;

import java.io.IOException;

import org.gvsig.fmap.dal.coverage.RasterLocator;

import org.gvsig.fmap.dal.coverage.dataset.Buffer;

import org.gvsig.fmap.dal.coverage.datastruct.BandList;

import org.gvsig.fmap.dal.coverage.datastruct.Extent;

import org.gvsig.fmap.dal.coverage.exception.NotSupportedExtensionException;

import org.gvsig.fmap.dal.coverage.exception.ProcessInterruptedException;

import org.gvsig.fmap.dal.coverage.exception.QueryException;

import org.gvsig.fmap.dal.coverage.exception.RasterDriverException;

import org.gvsig.fmap.dal.coverage.store.RasterDataStore;

import org.gvsig.fmap.dal.coverage.store.RasterQuery;

import org.gvsig.fmap.dal.coverage.store.props.ColorInterpretation;

import org.gvsig.raster.cache.tile.Tile;

import org.gvsig.raster.cache.tile.exception.TileGettingException;

import org.gvsig.raster.cache.tile.provider.CacheStruct;

import org.gvsig.raster.impl.DefaultRasterManager;

import org.gvsig.raster.impl.datastruct.ExtentImpl;

/** 

 * Tile getter 

 * @author Nacho Brodin (nachobrodin@gmail.com)

 */

public class TileDownloaderForFiles extends BaseTileDownloader {

        private CacheStruct               struct     = null;

        private String                    extension  = null;

        public TileDownloaderForFiles(RasterDataStore store, 

                        CacheStruct struct,

                        int tileWidth,

                        int tileHeight,

                        String extension) {

                super(store, tileWidth, tileHeight);

                this.struct = struct;

                this.extension = extension;

        }

        public synchronized Tile downloadTile(Tile tile) throws TileGettingException {

                Extent tileExtent = new ExtentImpl(tile.getUl(), tile.getLr());

                ColorInterpretation ci = store.getColorInterpretation();

                //Escribe todas las bandas a disco

                BandList newBandList = store.getDefaultBandList();//createBandList(prov);

                Buffer bufResult = null;

                double pixelSize = struct.getPixelSizeByLevel(tile.getLevel());

                try {

                        Extent ex = store.getExtent().intersection(tileExtent);

                        //newBuf ser?n distintas de tilePx cuando haya zonas con valores no data. Las de los bordes

                        int newBufWidth = (int)Math.ceil((ex.width() * this.tilePxWidth) / tileExtent.width());

                        int newBufHeight = (int)Math.ceil((ex.height() * this.tilePxHeight) / tileExtent.height());

                        boolean alphaBand = false;

                        int nBandsBuffer = store.getBandCount();

                        if(store.getColorInterpretation().hasAlphaBand())

                                alphaBand = true;

                        //Si no hay parte del tile que cae fuera de la imagen no se usa una nueva banda de transparencia ni valores nodata

                        if(newBufHeight == this.tilePxHeight && newBufWidth == this.tilePxWidth) {

                                bufResult = readSupersampledBuffer(tileExtent, newBandList, this.tilePxWidth, this.tilePxHeight, nBandsBuffer);

                                if(bufResult == null) {

                                        RasterQuery q = RasterLocator.getManager().createQuery();

                                        q.setAreaOfInterest(tileExtent, this.tilePxWidth, this.tilePxHeight);

                                        q.setAllDrawableBands();

                                        q.setAdjustToExtent(true); 

                                        bufResult = store.query(q);

                                }

                        } else {

                                //Hay parte del tile que cae fuera de la imagen

                                if(store.getDataType()[0] == Buffer.TYPE_BYTE) {

                                        //Para imagenes byte se crea una banda de transparencia

                                        alphaBand = true;

                                        if(!store.getColorInterpretation().hasAlphaBand())

                                                nBandsBuffer ++; 

                                } 

                                Buffer smallBuf = readSupersampledBuffer(ex, newBandList, newBufWidth, newBufHeight, nBandsBuffer);

                                if(smallBuf == null) { //No ha habido resampleo

                                        RasterQuery q = RasterLocator.getManager().createQuery();

                                        q.setAreaOfInterest(ex, newBufWidth, newBufHeight);

                                        q.setAllDrawableBands();

                                        q.setAdjustToExtent(true); 

                                        smallBuf = store.query(q);

                                }

                                bufResult = buildTileBuffer(nBandsBuffer, this.tilePxWidth, this.tilePxHeight);

                                RasterLocator.getManager().getRasterUtils().copyToBuffer(

                                                bufResult, 

                                                tileExtent, 

                                                smallBuf, 

                                                ex, 

                                                pixelSize, 

                                                store.getColorInterpretation().hasAlphaBand());

                        }

                        saveTile(bufResult, pixelSize, extension, alphaBand, tile, tileExtent, ci);

                        //Si borramos el rmf no se puede leer la etiqueta Alpha. En caso de que se modifique jgdal para

                        //poder guardar esta etiqueta deberiamos borrar el rmf para ahorrar ficheros

                        //File rmf = new File(tile.getFile().getAbsolutePath() + ".rmf");

                        //if(rmf.exists())

                                //rmf.delete();

                } catch (ProcessInterruptedException e) {

                } catch (RasterDriverException e) {

                        throw new TileGettingException(e);

                } catch (NotSupportedExtensionException e) {

                        throw new TileGettingException(e);

                } catch (IOException e) {

                        throw new TileGettingException(e);

                } catch (QueryException e) {

                        throw new TileGettingException(e);

                }

                readTileFromDisk(tile);

                return tile;

        }

        /**

         * When the buffer of the request is greater than the original raster (> scale 1:1) then the request 

         * has to be resampled. 

         * @param tileExtent

         * @param newBandList

         * @param bufWidth

         * @param bufHeight

         * @param nBands

         * @return

         * @throws ProcessInterruptedException

         * @throws TileGettingException

         */

        private Buffer readSupersampledBuffer(Extent tileExtent, BandList newBandList, int bufWidth, int bufHeight, int nBands) throws ProcessInterruptedException, TileGettingException {

                int widthImgPx = (int)Math.abs(tileExtent.width() / store.getPixelSizeX());

                int heightImgPx = (int)Math.abs(tileExtent.height() / store.getPixelSizeY());

                boolean supersampling = ((bufWidth > widthImgPx) || (bufHeight > heightImgPx)) ? true : false;

                if(supersampling) {

                        RasterQuery q = RasterLocator.getManager().createQuery();

                        q.setAreaOfInterest(tileExtent, widthImgPx, heightImgPx);

                        q.setAllDrawableBands();

                        q.setAdjustToExtent(true); 

                        Buffer buf = null;

                        try {

                                buf = store.query(q);

                        } catch (QueryException e) {

                                throw new TileGettingException(e);

                        }

                        Buffer result = buf.getAdjustedWindow(bufWidth, bufHeight, Buffer.INTERPOLATION_NearestNeighbour);

                        if(result != buf)

                                buf.dispose();

                        return result;

                }

                return null;

        }

        /**

         * Builds a buffer using the specified number of bands and initialize it

         * @param nbands

         * @return

         */

        private Buffer buildTileBuffer(int nbands, int w, int h) {

                Buffer bufResult = DefaultRasterManager.getInstance().createMemoryBuffer(store.getDataType()[0], w, h, nbands, true);

                if(store.getDataType()[0] != Buffer.TYPE_BYTE) {

                        for (int i = 0; i < bufResult.getBandCount(); i++) {

                                clearMaskBuffer(bufResult, i);

                        }

                } else

                        clearMaskBuffer(bufResult, nbands - 1);

                return bufResult;

        }

}