/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
*
* This 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 software 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 software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
package com.iiordanov.tigervnc.rfb;
import com.iiordanov.tigervnc.rdr.*;
public class ZRLEDecoder extends Decoder {
public ZRLEDecoder(CMsgReader reader_) {
reader = reader_;
zis = new ZlibInStream();
}
public void readRect(Rect r, CMsgHandler handler) {
InStream is = reader.getInStream();
int[] buf = reader.getImageBuf(64 * 64 * 4);
int bpp = handler.cp.pf().bpp;
int bytesPerPixel = (bpp > 24 ? 3 : bpp / 8);
boolean bigEndian = handler.cp.pf().bigEndian;
int length = is.readU32();
zis.setUnderlying(is, length);
Rect t = new Rect();
for (t.tl.y = r.tl.y; t.tl.y < r.br.y; t.tl.y += 64) {
t.br.y = Math.min(r.br.y, t.tl.y + 64);
for (t.tl.x = r.tl.x; t.tl.x < r.br.x; t.tl.x += 64) {
t.br.x = Math.min(r.br.x, t.tl.x + 64);
int mode = zis.readU8();
boolean rle = (mode & 128) != 0;
int palSize = mode & 127;
int[] palette = new int[128];
zis.readPixels(palette, palSize, bytesPerPixel, bigEndian);
if (palSize == 1) {
int pix = palette[0];
handler.fillRect(t, pix);
continue;
}
if (!rle) {
if (palSize == 0) {
// raw
zis.readPixels(buf, t.area(), bytesPerPixel, bigEndian);
} else {
// packed pixels
int bppp = ((palSize > 16) ? 8 :
((palSize > 4) ? 4 : ((palSize > 2) ? 2 : 1)));
int ptr = 0;
for (int i = 0; i < t.height(); i++) {
int eol = ptr + t.width();
int b = 0;
int nbits = 0;
while (ptr < eol) {
if (nbits == 0) {
b = zis.readU8();
nbits = 8;
}
nbits -= bppp;
int index = (b >> nbits) & ((1 << bppp) - 1) & 127;
buf[ptr++] = palette[index];
}
}
}
} else {
if (palSize == 0) {
// plain RLE
int ptr = 0;
int end = ptr + t.area();
while (ptr < end) {
int pix = zis.readPixel(bytesPerPixel, bigEndian);
int len = 1;
int b;
do {
b = zis.readU8();
len += b;
} while (b == 255);
if (!(len <= end - ptr))
throw new Exception("ZRLEDecoder: assertion (len <= end - ptr)"
+" failed");
while (len-- > 0) buf[ptr++] = pix;
}
} else {
// palette RLE
int ptr = 0;
int end = ptr + t.area();
while (ptr < end) {
int index = zis.readU8();
int len = 1;
if ((index & 128) != 0) {
int b;
do {
b = zis.readU8();
len += b;
} while (b == 255);
if (!(len <= end - ptr))
throw new Exception("ZRLEDecoder: assertion "
+"(len <= end - ptr) failed");
}
index &= 127;
int pix = palette[index];
while (len-- > 0) buf[ptr++] = pix;
}
}
}
handler.imageRect(t, buf);
}
}
zis.reset();
}
CMsgReader reader;
ZlibInStream zis;
}