/*
* polytoregion
*
* Scan converts a polygon by returning a run-length
* encoding of the resultant bitmap -- the run-length
* encoding is in the form of an array of rectangles.
*/
Region
XPolygonRegion(
XPoint *Pts, /* the pts */
int Count, /* number of pts */
int rule) /* winding rule */
{
Region region;
register EdgeTableEntry *pAET; /* Active Edge Table */
register int y; /* current scanline */
register int iPts = 0; /* number of pts in buffer */
register EdgeTableEntry *pWETE; /* Winding Edge Table Entry*/
register ScanLineList *pSLL; /* current scanLineList */
register XPoint *pts; /* output buffer */
EdgeTableEntry *pPrevAET; /* ptr to previous AET */
EdgeTable ET; /* header node for ET */
EdgeTableEntry AET; /* header node for AET */
EdgeTableEntry *pETEs; /* EdgeTableEntries pool */
ScanLineListBlock SLLBlock; /* header for scanlinelist */
int fixWAET = FALSE;
POINTBLOCK FirstPtBlock, *curPtBlock; /* PtBlock buffers */
POINTBLOCK *tmpPtBlock;
int numFullPtBlocks = 0;
if (! (region = XCreateRegion())) return (Region) NULL;
/* special case a rectangle */
pts = Pts;
if (((Count == 4) ||
((Count == 5) && (pts[4].x == pts[0].x) && (pts[4].y == pts[0].y))) &&
(((pts[0].y == pts[1].y) &&
(pts[1].x == pts[2].x) &&
(pts[2].y == pts[3].y) &&
(pts[3].x == pts[0].x)) ||
((pts[0].x == pts[1].x) &&
(pts[1].y == pts[2].y) &&
(pts[2].x == pts[3].x) &&
(pts[3].y == pts[0].y)))) {
region->extents.x1 = min(pts[0].x, pts[2].x);
region->extents.y1 = min(pts[0].y, pts[2].y);
region->extents.x2 = max(pts[0].x, pts[2].x);
region->extents.y2 = max(pts[0].y, pts[2].y);
if ((region->extents.x1 != region->extents.x2) &&
(region->extents.y1 != region->extents.y2)) {
region->numRects = 1;
*(region->rects) = region->extents;
}
return(region);
}
if (Count < 2) return region;
if (! (pETEs = Xmalloc(sizeof(EdgeTableEntry) * Count))) {
XDestroyRegion(region);
return (Region) NULL;
}
pts = FirstPtBlock.pts;
CreateETandAET(Count, Pts, &ET, &AET, pETEs, &SLLBlock);
pSLL = ET.scanlines.next;
curPtBlock = &FirstPtBlock;
if (rule == EvenOddRule) {
/*
* for each scanline
*/
for (y = ET.ymin; y < ET.ymax; y++) {
/*
* Add a new edge to the active edge table when we
* get to the next edge.
*/
if (pSLL != NULL && y == pSLL->scanline) {
loadAET(&AET, pSLL->edgelist);
pSLL = pSLL->next;
}
pPrevAET = &AET;
pAET = AET.next;
/*
* for each active edge
*/
while (pAET) {
pts->x = pAET->bres.minor_axis, pts->y = y;
pts++, iPts++;
/*
* send out the buffer
*/
if (iPts == NUMPTSTOBUFFER) {
tmpPtBlock = Xmalloc(sizeof(POINTBLOCK));
curPtBlock->next = tmpPtBlock;
curPtBlock = tmpPtBlock;
pts = curPtBlock->pts;
numFullPtBlocks++;
iPts = 0;
}
EVALUATEEDGEEVENODD(pAET, pPrevAET, y);
}
(void) InsertionSort(&AET);
}
}
else {
/*
* for each scanline
*/
for (y = ET.ymin; y < ET.ymax; y++) {
/*
* Add a new edge to the active edge table when we
* get to the next edge.
*/
if (pSLL != NULL && y == pSLL->scanline) {
loadAET(&AET, pSLL->edgelist);
computeWAET(&AET);
pSLL = pSLL->next;
}
pPrevAET = &AET;
pAET = AET.next;
pWETE = pAET;
/*
* for each active edge
*/
while (pAET) {
/*
* add to the buffer only those edges that
* are in the Winding active edge table.
*/
if (pWETE == pAET) {
pts->x = pAET->bres.minor_axis, pts->y = y;
pts++, iPts++;
/*
* send out the buffer
*/
if (iPts == NUMPTSTOBUFFER) {
tmpPtBlock = Xmalloc(sizeof(POINTBLOCK));
curPtBlock->next = tmpPtBlock;
curPtBlock = tmpPtBlock;
pts = curPtBlock->pts;
numFullPtBlocks++; iPts = 0;
}
pWETE = pWETE->nextWETE;
}
EVALUATEEDGEWINDING(pAET, pPrevAET, y, fixWAET);
}
/*
* recompute the winding active edge table if
* we just resorted or have exited an edge.
*/
if (InsertionSort(&AET) || fixWAET) {
computeWAET(&AET);
fixWAET = FALSE;
}
}
}
FreeStorage(SLLBlock.next);
(void) PtsToRegion(numFullPtBlocks, iPts, &FirstPtBlock, region);
for (curPtBlock = FirstPtBlock.next; --numFullPtBlocks >= 0;) {
tmpPtBlock = curPtBlock->next;
Xfree(curPtBlock);
curPtBlock = tmpPtBlock;
}
Xfree(pETEs);
return(region);
}
ubyte *lzw_expand( ubyte *inputbuf, ubyte *outputbuf, int length )
{
BIT_BUF *input;
unsigned int new_code;
unsigned int old_code;
int character;
unsigned int count;
int counter;
input = OpenInputBitBuf( inputbuf );
if ( outputbuf == NULL )
outputbuf = (ubyte *)malloc(length*sizeof(ubyte));
InitializeStorage();
counter = 0;
for ( ; ; )
{
InitializeDictionary();
old_code = (unsigned int) InputBits( input, current_code_bits );
if ( old_code == END_OF_STREAM )
{
CloseInputBitBuf( input );
return outputbuf;
}
character = old_code;
if (counter<length)
{
outputbuf[counter++] = ( ubyte ) old_code;
}
else
{
//printf( "ERROR:Tried to write %d\n", old_code );
//exit(1);
return 0;
}
for ( ; ; )
{
new_code = (unsigned int) InputBits( input, current_code_bits );
if ( new_code == END_OF_STREAM )
{
CloseInputBitBuf( input );
FreeStorage();
return outputbuf;
}
if ( new_code == FLUSH_CODE )
break;
if ( new_code == BUMP_CODE )
{
current_code_bits++;
continue;
}
if ( new_code >= next_code )
{
decode_stack[ 0 ] = (char) character;
count = decode_string( 1, old_code );
}
else
{
count = decode_string( 0, new_code );
}
character = decode_stack[ count - 1 ];
while ( count > 0 ) {
// This lets the case counter==length pass through.
// This is a hack.
if (counter<length) {
//printf("%x ", ( ubyte ) decode_stack[ count ]);
outputbuf[counter++] = ( ubyte ) decode_stack[ --count ];
} else if (counter>length) {
printf( "ERROR:Tried to write %d\n", decode_stack[ --count ] );
exit(1);
} else
count--;
}
dict[ next_code ].parent_code = old_code;
dict[ next_code ].character = (char) character;
next_code++;
old_code = new_code;
}
}
}
ByteBuffer::~ByteBuffer()
{
FreeStorage();
}
ubyte *lzw_compress( ubyte *inputbuf, ubyte *outputbuf, int input_size, int *output_size )
{
BIT_BUF *output;
int character;
int string_code;
unsigned int index;
int i;
output = OpenOutputBitBuf();
if ( outputbuf == NULL )
{
output->buf = (ubyte *)malloc(input_size*sizeof(ubyte));
if (output->buf == NULL)
{
//printf(" ERROR : OpenOutputBitBuf - Not enough memory to read buffer.\n");
//exit(1);
return NULL;
}
outputbuf = output->buf;
}
else
{
output->buf = outputbuf;
}
InitializeStorage();
InitializeDictionary();
string_code = ( *inputbuf++ );
for ( i=0 ; i<input_size ; i++ )
{
if (output->current_byte+4 >= input_size)
{
CloseOutputBitBuf( output );
FreeStorage();
free( outputbuf );
*output_size = -1;
return NULL;
}
character = ( *inputbuf++ );
index = find_child_node( string_code, character );
if ( dict[ index ].code_value != - 1 )
{
string_code = dict[ index ].code_value;
}
else
{
dict[ index ].code_value = next_code++;
dict[ index ].parent_code = string_code;
dict[ index ].character = (char) character;
OutputBits( output,(unsigned long) string_code, current_code_bits );
string_code = character;
if ( next_code > MAX_CODE )
{
OutputBits( output,(unsigned long) FLUSH_CODE, current_code_bits );
InitializeDictionary();
}
else if ( next_code > next_bump_code )
{
OutputBits( output,(unsigned long) BUMP_CODE, current_code_bits );
current_code_bits++;
next_bump_code <<= 1;
next_bump_code |= 1;
}
}
}
OutputBits( output, (unsigned long) string_code, current_code_bits );
OutputBits( output, (unsigned long) END_OF_STREAM, current_code_bits);
*output_size = output->current_byte + 1;
CloseOutputBitBuf( output );
FreeStorage();
return outputbuf;
}