Added Screenshot utility class. Fast Targa screenshot contributed by

Carsten Weisse of Bytonic Software.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@526 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 208 insertions, 0 deletions

diff --git a/src/classes/com/sun/opengl/utils/Screenshot.java b/src/classes/com/sun/opengl/utils/Screenshot.java
new file mode 100755
index 000000000..82e0bc0e1
--- /dev/null
+++ b/src/classes/com/sun/opengl/utils/Screenshot.java
@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) 2005 Sun Microsystems, Inc. All Rights Reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 
+ * - Redistribution of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 
+ * - Redistribution in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * 
+ * Neither the name of Sun Microsystems, Inc. or the names of
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * 
+ * This software is provided "AS IS," without a warranty of any kind. ALL
+ * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
+ * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
+ * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
+ * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
+ * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
+ * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
+ * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
+ * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+ * 
+ * You acknowledge that this software is not designed or intended for use
+ * in the design, construction, operation or maintenance of any nuclear
+ * facility.
+ */
+
+package com.sun.opengl.utils;
+
+import java.awt.image.*;
+import java.io.*;
+import java.nio.*;
+import java.nio.channels.*;
+import javax.imageio.*;
+
+import javax.media.opengl.*;
+import javax.media.opengl.glu.*;
+
+/** Utilities for taking screenshots of OpenGL applications. */
+
+public class Screenshot {
+  private static final int TARGA_HEADER_SIZE = 18;
+
+  /** 
+   * Takes a fast screenshot of the current OpenGL drawable to a Targa
+   * file. Requires the OpenGL context for the desired drawable to be
+   * current. This is the fastest mechanism for taking a screenshot of
+   * an application. Contributed by Carsten Weisse of Bytonic Software
+   * (http://bytonic.de/).
+   *
+   * @param file the file to write containing the screenshot
+   * @param width the width of the current drawable
+   * @param height the height of the current drawable
+   *
+   * @throws GLException if an OpenGL context was not current or
+   *   another OpenGL-related error occurred
+   * @throws IOException if an I/O error occurred while writing the
+   *   file
+   */
+  public static void writeToTargaFile(File file,
+                                      int width,
+                                      int height) throws GLException, IOException {
+    RandomAccessFile out = new RandomAccessFile(file, "rw");
+    FileChannel ch = out.getChannel();
+    int fileLength = TARGA_HEADER_SIZE + width * height * 3;
+    out.setLength(fileLength);
+    MappedByteBuffer image = ch.map(FileChannel.MapMode.READ_WRITE, 0, fileLength);
+
+    // write the TARGA header
+    image.put(0, (byte) 0).put(1, (byte) 0);
+    image.put(2, (byte) 2); // uncompressed type
+    image.put(12, (byte) (width & 0xFF)); // width
+    image.put(13, (byte) (width >> 8)); // width
+    image.put(14, (byte) (height & 0xFF)); // height
+    image.put(15, (byte) (height >> 8)); // height
+    image.put(16, (byte) 24); // pixel size
+             
+    // go to image data position
+    image.position(TARGA_HEADER_SIZE);
+    // jogl needs a sliced buffer
+    ByteBuffer bgr = image.slice();
+
+    GL gl = GLU.getCurrentGL();
+
+    // Set up pixel storage modes
+    PixelStorageModes psm = new PixelStorageModes();
+    psm.save(gl);
+
+    // read the BGR values into the image buffer
+    gl.glReadPixels(0, 0, width, height, GL.GL_BGR,
+                    GL.GL_UNSIGNED_BYTE, bgr);
+
+    // Restore pixel storage modes
+    psm.restore(gl);
+
+    // close the file channel
+    ch.close();
+  }
+
+  /**
+   * Takes a screenshot of the current OpenGL drawable to a
+   * BufferedImage. Requires the OpenGL context for the desired
+   * drawable to be current. Note that the scanlines of the resulting
+   * image are flipped vertically in order to correctly match the
+   * OpenGL contents, which takes time and is therefore not as fast as
+   * the Targa screenshot function.
+   *
+   * @param width the width of the current drawable
+   * @param height the height of the current drawable
+   *
+   * @throws GLException if an OpenGL context was not current or
+   *   another OpenGL-related error occurred
+   */
+  public static BufferedImage readToBufferedImage(int width,
+                                                  int height) throws GLException {
+    // Allocate necessary storage
+    BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);
+
+    GL gl = GLU.getCurrentGL();
+
+    // Set up pixel storage modes
+    PixelStorageModes psm = new PixelStorageModes();
+    psm.save(gl);
+
+    // read the BGR values into the image
+    gl.glReadPixels(0, 0, width, height, GL.GL_BGR,
+                    GL.GL_UNSIGNED_BYTE,
+                    ByteBuffer.wrap(((DataBufferByte) image.getRaster().getDataBuffer()).getData()));
+
+    // Restore pixel storage modes
+    psm.restore(gl);
+
+    // Must flip BufferedImage vertically for correct results
+    TextureIO.flipImageVertically(image);
+    return image;
+  }
+
+  /**
+   * Takes a screenshot of the current OpenGL drawable to the
+   * specified file on disk using the ImageIO package. Requires the
+   * OpenGL context for the desired drawable to be current. This is
+   * not the fastest mechanism for taking a screenshot but may be more
+   * convenient than others for getting images for consumption by
+   * other packages. The file format is inferred from the suffix of
+   * the given file.
+   *
+   * @throws GLException if an OpenGL context was not current or
+   *   another OpenGL-related error occurred
+   *
+   * @throws IOException if an I/O error occurred or if the file could
+   *   not be written to disk due to the requested file format being
+   *   unsupported by ImageIO
+   */
+  public static void writeToFile(File file,
+                                 int width,
+                                 int height) throws IOException, GLException {
+    BufferedImage image = readToBufferedImage(width, height);
+    if (!ImageIO.write(image, TextureIO.getFileSuffix(file), file)) {
+      throw new IOException("Unsupported file format " +
+                            TextureIO.getFileSuffix(file));
+    }
+  }
+
+  private static int glGetInteger(GL gl, int pname, int[] tmp) {
+    gl.glGetIntegerv(pname, tmp, 0);
+    return tmp[0];
+  }
+
+  static class PixelStorageModes {
+    int packAlignment;
+    int packRowLength;
+    int packSkipRows;
+    int packSkipPixels;
+    int packSwapBytes;
+    int[] tmp = new int[1];
+
+    void save(GL gl) {
+      packAlignment  = glGetInteger(gl, GL.GL_PACK_ALIGNMENT, tmp);
+      packRowLength  = glGetInteger(gl, GL.GL_PACK_ROW_LENGTH, tmp);
+      packSkipRows   = glGetInteger(gl, GL.GL_PACK_SKIP_ROWS, tmp);
+      packSkipPixels = glGetInteger(gl, GL.GL_PACK_SKIP_PIXELS, tmp);
+      packSwapBytes  = glGetInteger(gl, GL.GL_PACK_SWAP_BYTES, tmp);
+
+      gl.glPixelStorei(GL.GL_PACK_ALIGNMENT, 1);
+      gl.glPixelStorei(GL.GL_PACK_ROW_LENGTH, 0);
+      gl.glPixelStorei(GL.GL_PACK_SKIP_ROWS, 0);
+      gl.glPixelStorei(GL.GL_PACK_SKIP_PIXELS, 0);
+      gl.glPixelStorei(GL.GL_PACK_SWAP_BYTES, 0);
+    }
+
+    void restore(GL gl) {
+      gl.glPixelStorei(GL.GL_PACK_ALIGNMENT, packAlignment);
+      gl.glPixelStorei(GL.GL_PACK_ROW_LENGTH, packRowLength);
+      gl.glPixelStorei(GL.GL_PACK_SKIP_ROWS, packSkipRows);
+      gl.glPixelStorei(GL.GL_PACK_SKIP_PIXELS, packSkipPixels);
+      gl.glPixelStorei(GL.GL_PACK_SWAP_BYTES, packSwapBytes);
+    }
+  }
+}