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comparison dwt/internal/image/PngInputStream.d @ 34:5123b17c98ef

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Ported dwt.events.*, dwt.graphics.GC, Region, dwt.internal.image.*
author Jacob Carlborg <doob@me.com> <jacob.carlborg@gmail.com>
date Sun, 14 Sep 2008 01:45:57 +0200
parents b903c16b6f48
children
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33:965ac0a77267 34:5123b17c98ef
5 * which accompanies this distribution, and is available at 5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html 6 * http://www.eclipse.org/legal/epl-v10.html
7 * 7 *
8 * Contributors: 8 * Contributors:
9 * IBM Corporation - initial API and implementation 9 * IBM Corporation - initial API and implementation
10 * Port to the D programming language:
11 * Frank Benoit <benoit@tionex.de>
10 *******************************************************************************/ 12 *******************************************************************************/
11 module dwt.internal.image; 13 module dwt.internal.image.PngInputStream;
12 14
13 import java.io.IOException; 15 import dwt.dwthelper.InputStream;
14 import java.io.InputStream; 16 import dwt.dwthelper.System;
17 import dwt.internal.image.PngIdatChunk;
18 import dwt.internal.image.PngChunkReader;
19 import dwt.internal.image.PngChunk;
20
21 import tango.core.Exception;
22 import Math = tango.math.Math;
15 23
16 public class PngInputStream : InputStream { 24 public class PngInputStream : InputStream {
25
26 alias InputStream.read read;
27
17 PngChunkReader reader; 28 PngChunkReader reader;
18 PngChunk chunk; 29 PngChunk chunk;
19 int offset, length; 30 int offset, length;
20 31
21 final static int DATA_OFFSET = 8; 32 final static int DATA_OFFSET = 8;
22 33
23 public this(PngIdatChunk chunk, PngChunkReader reader) { 34 public this(PngIdatChunk chunk, PngChunkReader reader) {
24 this.chunk = chunk; 35 this.chunk = chunk;
25 this.reader = reader; 36 this.reader = reader;
26 length = chunk.getLength(); 37 length = chunk.getLength();
27 offset = 0; 38 offset = 0;
28 } 39 }
29 40
30 private bool checkChunk() { 41 private bool checkChunk() {
31 while (offset is length) { 42 while (offset is length) {
32 chunk = reader.readNextChunk(); 43 chunk = reader.readNextChunk();
33 if (chunk is null) throw new IOException(); 44 if (chunk is null) throw new IOException("no data");
34 if (chunk.getChunkType() is PngChunk.CHUNK_IEND) return false; 45 if (chunk.getChunkType() is PngChunk.CHUNK_IEND) return false;
35 if (chunk.getChunkType() !is PngChunk.CHUNK_IDAT) throw new IOException(); 46 if (chunk.getChunkType() !is PngChunk.CHUNK_IDAT) throw new IOException("");
36 length = chunk.getLength(); 47 length = chunk.getLength();
37 offset = 0; 48 offset = 0;
38 } 49 }
39 return true; 50 return true;
40 } 51 }
41 52
42 public void close() { 53 public override void close() {
43 chunk = null; 54 chunk = null;
44 } 55 }
45 56
46 public int read() { 57 public override int read() {
47 if (chunk is null) throw new IOException(); 58 if (chunk is null) throw new IOException("");
48 if (offset is length && !checkChunk()) return -1; 59 if (offset is length && !checkChunk()) return -1;
49 int b = chunk.reference[DATA_OFFSET + offset] & 0xFF; 60 int b = chunk.reference[DATA_OFFSET + offset] & 0xFF;
50 offset++; 61 offset++;
51 return b; 62 return b;
52 } 63 }
53 64
54 public int read(byte[] b, int off, int len) { 65 public override int read(byte[] b, int off, int len) {
55 if (chunk is null) throw new IOException(); 66 if (chunk is null) throw new IOException("");
56 if (offset is length && !checkChunk()) return -1; 67 if (offset is length && !checkChunk()) return -1;
57 len = Math.min(len, length - offset); 68 len = Math.min(len, length - offset);
58 System.arraycopy(chunk.reference, DATA_OFFSET + offset, b, off, len); 69 System.arraycopy(chunk.reference, DATA_OFFSET + offset, b, off, len);
59 offset += len; 70 offset += len;
60 return len; 71 return len;