don't depend on sharedrawweb

use directly sharedrawweb java code here Signed-off-by: philippe lhardy <philippe.lhardy@astrolabe.coop>
2025-11-02 18:03:10 +01:00
parent e78da6ec76
commit 36e58808d5
16 changed files with 1383 additions and 13 deletions
--- a/java/org/artisanlogiciel/compression/graphics/BitFieldWriter.java
+++ b/java/org/artisanlogiciel/compression/graphics/BitFieldWriter.java
@@ -0,0 +1,125 @@
+/*
+    This file is part of ShareDrawWeb.
+
+    ShareDrawWeb 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.
+
+    ShareDrawWeb 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 ShareDrawWeb; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+ */
+
+package org.artisanlogiciel.compression.graphics;
+
+/*
+  simple class to write bitfields
+  @see BitFieldReader
+  @author Philippe Lhardy
+*/
+
+import java.io.*;
+
+class BitFieldWriter {
+
+   // size of nextWord
+   final int dataSize = 32;
+
+   /* bitOffset is number of bits already used in word
+      should ensure bitOffset < dataSize
+    */
+   private int bitOffset;
+
+   /* word used waiting to be filled to be written
+      dataSize is bit size of nextWord
+    */
+   private int nextWord;
+
+   private DataOutputStream outputStream;
+
+   public void write( int field, int bits) throws java.io.IOException {
+     // if more bits needed that word currently used.
+     if ( bits  + bitOffset > dataSize) {
+       // warning recursive call ( not terminal )
+       // fill and write current word
+       int bitsize = dataSize - bitOffset;
+       int head;
+       // most significant bits first
+       // suppress at left least significant bits
+       head = field >> (bits - bitsize);
+       write( head, dataSize - bitOffset);
+       // no need of newWord() previous write already done it
+       // least significant bits last
+       field = field & ( 0x7FFFFFFF >> ( bitsize - 1));
+       write( field, bits - bitsize);
+     }
+     else {         
+       if ( bits == dataSize ) {
+         // special case to keep sign
+         nextWord = field; 
+         bitOffset = 0;
+       }
+       else {
+         // keep only meaning part of field
+         field = field & ( 0x7FFFFFFF >> ( dataSize - 1 - bits));
+         nextWord = nextWord | ( field << ( dataSize - bits - bitOffset));
+         bitOffset = ( bitOffset + bits ) % dataSize; 
+       }       
+       // a new word is needed
+       if ( bitOffset == 0 ) {
+         newWord();
+       }
+     }
+     /*
+     System.out.println( "nextWord " + Integer.toString( nextWord) + " size "
+        + Integer.toString( bits) + " field " + Integer.toString( field));
+     */
+   }
+
+    /**
+     * seems to works correctly as DataOutputStream.writeInt()
+     */
+    private void writeInt( int i)
+    throws IOException
+    {
+	long j = i;
+	byte bytes[]=new byte[4];
+	bytes[0] = (byte) ((j & 0xFF000000) >> 24);
+	bytes[1] = (byte) ((j & 0x00FF0000) >> 16);
+	bytes[2] = (byte) ((j & 0x0000FF00) >> 8);
+	bytes[3] = (byte) (j & 0x000000FF);
+	outputStream.write( bytes, 0, 4);
+    }
+
+   private void newWord() throws java.io.IOException {
+     // do really write current word;
+       //writeInt( nextWord);
+     outputStream.writeInt(nextWord);
+     // reset nextWord
+     bitOffset = 0;
+     nextWord = 0;
+   }
+
+   /*
+    write all current datas if any
+    to have a clean word ready.
+    */
+   public void padToWord() throws java.io.IOException {
+     if ( bitOffset != 0) {
+       newWord();
+     }
+   }
+
+   /* set OutputStream */
+   public void setOutputStream( OutputStream output) {
+     outputStream = new DataOutputStream(output);
+   }
+
+}