A utility class for generating a trimmed tileset (and associated trimmed

image) from some other (presumably non-trimmed) tileset.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@1489 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/tile/util/TileSetTrimmer.java

@@ -0,0 +1,114 @@
+//
+// $Id: TileSetTrimmer.java,v 1.1 2002/06/19 08:29:59 mdb Exp $
+
+package com.threerings.media.tile.util;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import java.awt.Rectangle;
+import java.awt.image.BufferedImage;
+import java.awt.image.Raster;
+import java.awt.image.WritableRaster;
+
+import javax.imageio.ImageIO;
+
+import com.samskivert.util.StringUtil;
+
+import com.threerings.media.Log;
+
+import com.threerings.media.tile.NoSuchTileException;
+import com.threerings.media.tile.Tile;
+import com.threerings.media.tile.TileSet;
+import com.threerings.media.tile.TrimmedTileSet;
+import com.threerings.media.util.ImageUtil;
+
+/**
+ * Contains routines for generating a trimmed tileset from an existing
+ * tileset. Both a {@link TrimmedTileSet} instance and the associated
+ * trimmed image are created.
+ */
+public class TileSetTrimmer
+{
+    /**
+     * Generates a {@link TrimmedTileSet} from the supplied source
+     * tileset. The source tileset must be configured with an image
+     * provider so that the tile images can be obtained. The tile images
+     * will be trimmed and a new tileset image generated and written to
+     * the <code>destImage</code> output stream argument.
+     *
+     * @param source the source tileset.
+     * @param destImage an output stream to which the new trimmed image
+     * will be written.
+     */
+    public static TrimmedTileSet trimTileSet (
+        TileSet source, OutputStream destImage)
+        throws IOException
+    {
+        int tcount = source.getTileCount();
+        BufferedImage[] timgs = new BufferedImage[tcount];
+
+        // these will contain the width and height of the untrimmed tile,
+        // but the x and y offset of the trimmed tile image in the
+        // supplied tileset source image
+        Rectangle[] obounds = new Rectangle[tcount];
+
+        // these will contain the bounds of the trimmed image in the
+        // coordinate system defined by the untrimmed image
+        Rectangle[] tbounds = new Rectangle[tcount];
+
+        // compute some tile metrics
+        int nextx = 0, maxy = 0;
+        for (int ii = 0; ii < tcount; ii++) {
+            // extract the image from the original tileset
+            try {
+                Tile tile = source.getTile(ii);
+                timgs[ii] = (BufferedImage)tile.getImage();
+            } catch (NoSuchTileException nste) {
+                throw new RuntimeException("WTF? No such tile [tset=" + source +
+                                           ", tidx=" + ii + "]");
+            }
+
+            // figure out how tightly we can trim it
+            obounds[ii] = new Rectangle(
+                0, 0, timgs[ii].getWidth(), timgs[ii].getHeight());
+            tbounds[ii] = new Rectangle();
+            ImageUtil.computeTrimmedBounds(timgs[ii], tbounds[ii]);
+
+            // assign it a location in the trimmed tile image
+            obounds[ii].x = nextx;
+            nextx += tbounds[ii].width;
+            maxy = Math.max(maxy, tbounds[ii].height);
+        }
+
+        // create our tileset object
+        TrimmedTileSet ttset = new TrimmedTileSet();
+        ttset.setTileMetrics(obounds, tbounds);
+
+//         Log.info("Trimming [obounds=" + StringUtil.toString(obounds) +
+//                  ", tbounds=" + StringUtil.toString(tbounds) +
+//                  ", nwidth=" + nextx + ", nheight=" + maxy + "].");
+
+        // create the new tileset image
+        BufferedImage image = ImageUtil.createCompatibleImage(
+            (BufferedImage)source.getTileSetImage(), nextx, maxy);
+
+        // copy the tile data
+        WritableRaster drast = image.getRaster();
+        int xoff = 0;
+        for (int ii = 0; ii < tcount; ii++) {
+            Rectangle tb = tbounds[ii];
+            Raster srast = timgs[ii].getRaster().createChild(
+                tb.x, tb.y, tb.width, tb.height, 0, 0, null);
+            drast.setRect(xoff, 0, srast);
+            xoff += tb.width;
+        }
+
+        // write out trimmed image
+        ImageIO.write(image, "png", destImage);
+
+        // we're good to go
+        return ttset;
+    }
+}