001: /*
002: * $RCSfile: GeometryCompressor.java,v $
003: *
004: * Copyright (c) 2007 Sun Microsystems, Inc. All rights reserved.
005: *
006: * Redistribution and use in source and binary forms, with or without
007: * modification, are permitted provided that the following conditions
008: * are met:
009: *
010: * - Redistribution of source code must retain the above copyright
011: * notice, this list of conditions and the following disclaimer.
012: *
013: * - Redistribution in binary form must reproduce the above copyright
014: * notice, this list of conditions and the following disclaimer in
015: * the documentation and/or other materials provided with the
016: * distribution.
017: *
018: * Neither the name of Sun Microsystems, Inc. or the names of
019: * contributors may be used to endorse or promote products derived
020: * from this software without specific prior written permission.
021: *
022: * This software is provided "AS IS," without a warranty of any
023: * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
024: * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
025: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
026: * EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
027: * NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF
028: * USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
029: * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR
030: * ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
031: * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
032: * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
033: * INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
034: * POSSIBILITY OF SUCH DAMAGES.
035: *
036: * You acknowledge that this software is not designed, licensed or
037: * intended for use in the design, construction, operation or
038: * maintenance of any nuclear facility.
039: *
040: * $Revision: 1.3 $
041: * $Date: 2007/02/09 17:20:22 $
042: * $State: Exp $
043: */
044:
045: package com.sun.j3d.utils.geometry.compression;
046:
047: import java.io.IOException;
048: import javax.vecmath.Point3d;
049:
050: /**
051: * A GeometryCompressor takes a stream of geometric elements and
052: * quantization parameters (the CompressionStream object) and
053: * compresses it into a stream of commands as defined by appendix B
054: * of the Java 3D specification. The resulting data may be output
055: * in the form of a CompressedGeometryData node component or appended
056: * to a CompressedGeometryFile.
057: *
058: * @see CompressionStream
059: * @see CompressedGeometryData
060: * @see CompressedGeometryFile
061: *
062: * @since Java 3D 1.5
063: */
064: public class GeometryCompressor {
065: private static final boolean benchmark = false;
066: private static final boolean printStream = false;
067: private static final boolean printHuffman = false;
068:
069: private HuffmanTable huffmanTable;
070: private CommandStream outputBuffer;
071: private CompressedGeometryData.Header cgHeader;
072: private long startTime;
073:
074: public GeometryCompressor() {
075: // Create a compressed geometry header.
076: cgHeader = new CompressedGeometryData.Header();
077:
078: // v1.0.0 - pre-FCS
079: // v1.0.1 - fixed winding order, FCS version (J3D 1.1.2)
080: // v1.0.2 - normal component length maximum 6, LII hardware (J3D 1.2)
081: cgHeader.majorVersionNumber = 1;
082: cgHeader.minorVersionNumber = 0;
083: cgHeader.minorMinorVersionNumber = 2;
084: }
085:
086: /**
087: * Compress a stream into a CompressedGeometryData node component.
088: *
089: *
090: * @param stream CompressionStream containing the geometry to be compressed
091: * @return a CompressedGeometryData node component
092: */
093: public CompressedGeometryData compress(CompressionStream stream) {
094: CompressedGeometryData cg;
095:
096: compressStream(stream);
097: cg = new CompressedGeometryData(cgHeader, outputBuffer
098: .getBytes());
099:
100: outputBuffer.clear();
101: return cg;
102: }
103:
104: /**
105: * Compress a stream and append the output to a CompressedGeometryFile.
106: * The resource remains open for subsequent updates; its close() method
107: * must be called to create a valid compressed geometry resource file.
108: *
109: * @param stream CompressionStream containing the geometry to be compressed
110: * @param f a currently open CompressedGeometryFile with write access
111: * @exception IOException if write fails
112: */
113: public void compress(CompressionStream stream,
114: CompressedGeometryFile f) throws IOException {
115:
116: compressStream(stream);
117: f.write(cgHeader, outputBuffer.getBytes());
118:
119: outputBuffer.clear();
120: }
121:
122: //
123: // Compress the stream and put the results in the output buffer.
124: // Set up the CompressedGeometryData.Header object.
125: //
126: private void compressStream(CompressionStream stream) {
127: if (benchmark)
128: startTime = System.currentTimeMillis();
129:
130: // Create the Huffman table.
131: huffmanTable = new HuffmanTable();
132:
133: // Quantize the stream, compute deltas between consecutive elements if
134: // possible, and histogram the data length distribution.
135: stream.quantize(huffmanTable);
136:
137: // Compute tags for stream tokens.
138: huffmanTable.computeTags();
139:
140: // Create the output buffer and assemble the compressed output.
141: outputBuffer = new CommandStream(stream.getByteCount() / 3);
142: stream.outputCommands(huffmanTable, outputBuffer);
143:
144: // Print any desired info.
145: if (benchmark)
146: printBench(stream);
147: if (printStream)
148: stream.print();
149: if (printHuffman)
150: huffmanTable.print();
151:
152: // Set up the compressed geometry header object.
153: cgHeader.bufferType = stream.streamType;
154: cgHeader.bufferDataPresent = 0;
155: cgHeader.lowerBound = new Point3d(stream.ncBounds[0]);
156: cgHeader.upperBound = new Point3d(stream.ncBounds[1]);
157:
158: if (stream.vertexNormals)
159: cgHeader.bufferDataPresent |= CompressedGeometryData.Header.NORMAL_IN_BUFFER;
160:
161: if (stream.vertexColor3 || stream.vertexColor4)
162: cgHeader.bufferDataPresent |= CompressedGeometryData.Header.COLOR_IN_BUFFER;
163:
164: if (stream.vertexColor4)
165: cgHeader.bufferDataPresent |= CompressedGeometryData.Header.ALPHA_IN_BUFFER;
166:
167: cgHeader.start = 0;
168: cgHeader.size = outputBuffer.getByteCount();
169:
170: // Clear the huffman table for next use.
171: huffmanTable.clear();
172: }
173:
174: private void printBench(CompressionStream stream) {
175: long t = System.currentTimeMillis() - startTime;
176: int vertexCount = stream.getVertexCount();
177: int meshReferenceCount = stream.getMeshReferenceCount();
178: int totalVertices = meshReferenceCount + vertexCount;
179: float meshPercent = 100f * meshReferenceCount
180: / (float) totalVertices;
181:
182: float compressionRatio = stream.getByteCount()
183: / ((float) outputBuffer.getByteCount());
184:
185: int vertexBytes = 12 + (stream.vertexColor3 ? 12 : 0)
186: + (stream.vertexColor4 ? 16 : 0)
187: + (stream.vertexNormals ? 12 : 0);
188:
189: float compressedVertexBytes = outputBuffer.getByteCount()
190: / (float) totalVertices;
191:
192: System.out.println("\nGeometryCompressor:\n" + totalVertices
193: + " total vertices\n" + vertexCount
194: + " streamed vertices\n" + meshReferenceCount
195: + " mesh buffer references (" + meshPercent + "%)\n"
196: + stream.getByteCount()
197: + " bytes streamed geometry compressed to "
198: + outputBuffer.getByteCount() + " in " + (t / 1000f)
199: + " sec\n" + (stream.getByteCount() / (float) t)
200: + " kbytes/sec, " + "stream compression ratio "
201: + compressionRatio + "\n\n" + vertexBytes
202: + " original bytes per vertex, "
203: + compressedVertexBytes
204: + " compressed bytes per vertex\n"
205: + "total vertex compression ratio "
206: + (vertexBytes / (float) compressedVertexBytes)
207: + "\n\n" + "lower bound "
208: + stream.ncBounds[0].toString() + "\n" + "upper bound "
209: + stream.ncBounds[1].toString());
210: }
211: }
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