forked from AuroraMiddleware/gtk
628 lines
18 KiB
C
628 lines
18 KiB
C
/* $TOG: PolyReg.c /main/15 1998/02/06 17:47:08 kaleb $ */
|
||
/************************************************************************
|
||
|
||
Copyright 1987, 1998 The Open Group
|
||
|
||
All Rights Reserved.
|
||
|
||
The above copyright notice and this permission notice shall be included in
|
||
all copies or substantial portions of the Software.
|
||
|
||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
|
||
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
|
||
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
||
|
||
Except as contained in this notice, the name of The Open Group shall not be
|
||
used in advertising or otherwise to promote the sale, use or other dealings
|
||
in this Software without prior written authorization from The Open Group.
|
||
|
||
|
||
Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
|
||
|
||
All Rights Reserved
|
||
|
||
Permission to use, copy, modify, and distribute this software and its
|
||
documentation for any purpose and without fee is hereby granted,
|
||
provided that the above copyright notice appear in all copies and that
|
||
both that copyright notice and this permission notice appear in
|
||
supporting documentation, and that the name of Digital not be
|
||
used in advertising or publicity pertaining to distribution of the
|
||
software without specific, written prior permission.
|
||
|
||
DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
|
||
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
|
||
DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
|
||
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
|
||
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
|
||
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
|
||
SOFTWARE.
|
||
|
||
************************************************************************/
|
||
/* $XFree86: xc/lib/X11/PolyReg.c,v 1.4 1998/10/03 08:41:21 dawes Exp $ */
|
||
|
||
#define LARGE_COORDINATE 1000000
|
||
#define SMALL_COORDINATE -LARGE_COORDINATE
|
||
|
||
#include "config.h"
|
||
#include <gdkregion.h>
|
||
#include "gdkregion-generic.h"
|
||
#include "gdkpoly-generic.h"
|
||
#include "gdkalias.h"
|
||
|
||
/*
|
||
* InsertEdgeInET
|
||
*
|
||
* Insert the given edge into the edge table.
|
||
* First we must find the correct bucket in the
|
||
* Edge table, then find the right slot in the
|
||
* bucket. Finally, we can insert it.
|
||
*
|
||
*/
|
||
static void
|
||
InsertEdgeInET (EdgeTable *ET,
|
||
EdgeTableEntry *ETE,
|
||
int scanline,
|
||
ScanLineListBlock **SLLBlock,
|
||
int *iSLLBlock)
|
||
{
|
||
EdgeTableEntry *start, *prev;
|
||
ScanLineList *pSLL, *pPrevSLL;
|
||
ScanLineListBlock *tmpSLLBlock;
|
||
|
||
/*
|
||
* find the right bucket to put the edge into
|
||
*/
|
||
pPrevSLL = &ET->scanlines;
|
||
pSLL = pPrevSLL->next;
|
||
while (pSLL && (pSLL->scanline < scanline))
|
||
{
|
||
pPrevSLL = pSLL;
|
||
pSLL = pSLL->next;
|
||
}
|
||
|
||
/*
|
||
* reassign pSLL (pointer to ScanLineList) if necessary
|
||
*/
|
||
if ((!pSLL) || (pSLL->scanline > scanline))
|
||
{
|
||
if (*iSLLBlock > SLLSPERBLOCK-1)
|
||
{
|
||
tmpSLLBlock =
|
||
(ScanLineListBlock *)g_malloc(sizeof(ScanLineListBlock));
|
||
(*SLLBlock)->next = tmpSLLBlock;
|
||
tmpSLLBlock->next = (ScanLineListBlock *)NULL;
|
||
*SLLBlock = tmpSLLBlock;
|
||
*iSLLBlock = 0;
|
||
}
|
||
pSLL = &((*SLLBlock)->SLLs[(*iSLLBlock)++]);
|
||
|
||
pSLL->next = pPrevSLL->next;
|
||
pSLL->edgelist = (EdgeTableEntry *)NULL;
|
||
pPrevSLL->next = pSLL;
|
||
}
|
||
pSLL->scanline = scanline;
|
||
|
||
/*
|
||
* now insert the edge in the right bucket
|
||
*/
|
||
prev = (EdgeTableEntry *)NULL;
|
||
start = pSLL->edgelist;
|
||
while (start && (start->bres.minor_axis < ETE->bres.minor_axis))
|
||
{
|
||
prev = start;
|
||
start = start->next;
|
||
}
|
||
ETE->next = start;
|
||
|
||
if (prev)
|
||
prev->next = ETE;
|
||
else
|
||
pSLL->edgelist = ETE;
|
||
}
|
||
|
||
/*
|
||
* CreateEdgeTable
|
||
*
|
||
* This routine creates the edge table for
|
||
* scan converting polygons.
|
||
* The Edge Table (ET) looks like:
|
||
*
|
||
* EdgeTable
|
||
* --------
|
||
* | ymax | ScanLineLists
|
||
* |scanline|-->------------>-------------->...
|
||
* -------- |scanline| |scanline|
|
||
* |edgelist| |edgelist|
|
||
* --------- ---------
|
||
* | |
|
||
* | |
|
||
* V V
|
||
* list of ETEs list of ETEs
|
||
*
|
||
* where ETE is an EdgeTableEntry data structure,
|
||
* and there is one ScanLineList per scanline at
|
||
* which an edge is initially entered.
|
||
*
|
||
*/
|
||
|
||
static void
|
||
CreateETandAET (int count,
|
||
const GdkPoint *pts,
|
||
EdgeTable *ET,
|
||
EdgeTableEntry *AET,
|
||
EdgeTableEntry *pETEs,
|
||
ScanLineListBlock *pSLLBlock)
|
||
{
|
||
const GdkPoint *top, *bottom;
|
||
const GdkPoint *PrevPt, *CurrPt;
|
||
int iSLLBlock = 0;
|
||
int dy;
|
||
|
||
if (count < 2) return;
|
||
|
||
/*
|
||
* initialize the Active Edge Table
|
||
*/
|
||
AET->next = (EdgeTableEntry *)NULL;
|
||
AET->back = (EdgeTableEntry *)NULL;
|
||
AET->nextWETE = (EdgeTableEntry *)NULL;
|
||
AET->bres.minor_axis = SMALL_COORDINATE;
|
||
|
||
/*
|
||
* initialize the Edge Table.
|
||
*/
|
||
ET->scanlines.next = (ScanLineList *)NULL;
|
||
ET->ymax = SMALL_COORDINATE;
|
||
ET->ymin = LARGE_COORDINATE;
|
||
pSLLBlock->next = (ScanLineListBlock *)NULL;
|
||
|
||
PrevPt = &pts[count-1];
|
||
|
||
/*
|
||
* for each vertex in the array of points.
|
||
* In this loop we are dealing with two vertices at
|
||
* a time -- these make up one edge of the polygon.
|
||
*/
|
||
while (count--)
|
||
{
|
||
CurrPt = pts++;
|
||
|
||
/*
|
||
* find out which point is above and which is below.
|
||
*/
|
||
if (PrevPt->y > CurrPt->y)
|
||
{
|
||
bottom = PrevPt, top = CurrPt;
|
||
pETEs->ClockWise = 0;
|
||
}
|
||
else
|
||
{
|
||
bottom = CurrPt, top = PrevPt;
|
||
pETEs->ClockWise = 1;
|
||
}
|
||
|
||
/*
|
||
* don't add horizontal edges to the Edge table.
|
||
*/
|
||
if (bottom->y != top->y)
|
||
{
|
||
pETEs->ymax = bottom->y-1; /* -1 so we don't get last scanline */
|
||
|
||
/*
|
||
* initialize integer edge algorithm
|
||
*/
|
||
dy = bottom->y - top->y;
|
||
BRESINITPGONSTRUCT(dy, top->x, bottom->x, pETEs->bres);
|
||
|
||
InsertEdgeInET(ET, pETEs, top->y, &pSLLBlock, &iSLLBlock);
|
||
|
||
if (PrevPt->y > ET->ymax)
|
||
ET->ymax = PrevPt->y;
|
||
if (PrevPt->y < ET->ymin)
|
||
ET->ymin = PrevPt->y;
|
||
pETEs++;
|
||
}
|
||
|
||
PrevPt = CurrPt;
|
||
}
|
||
}
|
||
|
||
/*
|
||
* loadAET
|
||
*
|
||
* This routine moves EdgeTableEntries from the
|
||
* EdgeTable into the Active Edge Table,
|
||
* leaving them sorted by smaller x coordinate.
|
||
*
|
||
*/
|
||
|
||
static void
|
||
loadAET(EdgeTableEntry *AET,
|
||
EdgeTableEntry *ETEs)
|
||
{
|
||
EdgeTableEntry *pPrevAET;
|
||
EdgeTableEntry *tmp;
|
||
|
||
pPrevAET = AET;
|
||
AET = AET->next;
|
||
while (ETEs)
|
||
{
|
||
while (AET && (AET->bres.minor_axis < ETEs->bres.minor_axis))
|
||
{
|
||
pPrevAET = AET;
|
||
AET = AET->next;
|
||
}
|
||
tmp = ETEs->next;
|
||
ETEs->next = AET;
|
||
if (AET)
|
||
AET->back = ETEs;
|
||
ETEs->back = pPrevAET;
|
||
pPrevAET->next = ETEs;
|
||
pPrevAET = ETEs;
|
||
|
||
ETEs = tmp;
|
||
}
|
||
}
|
||
|
||
/*
|
||
* computeWAET
|
||
*
|
||
* This routine links the AET by the
|
||
* nextWETE (winding EdgeTableEntry) link for
|
||
* use by the winding number rule. The final
|
||
* Active Edge Table (AET) might look something
|
||
* like:
|
||
*
|
||
* AET
|
||
* ---------- --------- ---------
|
||
* |ymax | |ymax | |ymax |
|
||
* | ... | |... | |... |
|
||
* |next |->|next |->|next |->...
|
||
* |nextWETE| |nextWETE| |nextWETE|
|
||
* --------- --------- ^--------
|
||
* | | |
|
||
* V-------------------> V---> ...
|
||
*
|
||
*/
|
||
static void
|
||
computeWAET (EdgeTableEntry *AET)
|
||
{
|
||
EdgeTableEntry *pWETE;
|
||
int inside = 1;
|
||
int isInside = 0;
|
||
|
||
AET->nextWETE = (EdgeTableEntry *)NULL;
|
||
pWETE = AET;
|
||
AET = AET->next;
|
||
while (AET)
|
||
{
|
||
if (AET->ClockWise)
|
||
isInside++;
|
||
else
|
||
isInside--;
|
||
|
||
if ((!inside && !isInside) ||
|
||
( inside && isInside))
|
||
{
|
||
pWETE->nextWETE = AET;
|
||
pWETE = AET;
|
||
inside = !inside;
|
||
}
|
||
AET = AET->next;
|
||
}
|
||
pWETE->nextWETE = (EdgeTableEntry *)NULL;
|
||
}
|
||
|
||
/*
|
||
* InsertionSort
|
||
*
|
||
* Just a simple insertion sort using
|
||
* pointers and back pointers to sort the Active
|
||
* Edge Table.
|
||
*
|
||
*/
|
||
|
||
static int
|
||
InsertionSort (EdgeTableEntry *AET)
|
||
{
|
||
EdgeTableEntry *pETEchase;
|
||
EdgeTableEntry *pETEinsert;
|
||
EdgeTableEntry *pETEchaseBackTMP;
|
||
int changed = 0;
|
||
|
||
AET = AET->next;
|
||
while (AET)
|
||
{
|
||
pETEinsert = AET;
|
||
pETEchase = AET;
|
||
while (pETEchase->back->bres.minor_axis > AET->bres.minor_axis)
|
||
pETEchase = pETEchase->back;
|
||
|
||
AET = AET->next;
|
||
if (pETEchase != pETEinsert)
|
||
{
|
||
pETEchaseBackTMP = pETEchase->back;
|
||
pETEinsert->back->next = AET;
|
||
if (AET)
|
||
AET->back = pETEinsert->back;
|
||
pETEinsert->next = pETEchase;
|
||
pETEchase->back->next = pETEinsert;
|
||
pETEchase->back = pETEinsert;
|
||
pETEinsert->back = pETEchaseBackTMP;
|
||
changed = 1;
|
||
}
|
||
}
|
||
return(changed);
|
||
}
|
||
|
||
/*
|
||
* Clean up our act.
|
||
*/
|
||
static void
|
||
FreeStorage (ScanLineListBlock *pSLLBlock)
|
||
{
|
||
ScanLineListBlock *tmpSLLBlock;
|
||
|
||
while (pSLLBlock)
|
||
{
|
||
tmpSLLBlock = pSLLBlock->next;
|
||
g_free (pSLLBlock);
|
||
pSLLBlock = tmpSLLBlock;
|
||
}
|
||
}
|
||
|
||
/*
|
||
* Create an array of rectangles from a list of points.
|
||
* If indeed these things (POINTS, RECTS) are the same,
|
||
* then this proc is still needed, because it allocates
|
||
* storage for the array, which was allocated on the
|
||
* stack by the calling procedure.
|
||
*
|
||
*/
|
||
static int
|
||
PtsToRegion (int numFullPtBlocks,
|
||
int iCurPtBlock,
|
||
POINTBLOCK *FirstPtBlock,
|
||
GdkRegion *reg)
|
||
{
|
||
GdkRegionBox *rects;
|
||
GdkPoint *pts;
|
||
POINTBLOCK *CurPtBlock;
|
||
int i;
|
||
GdkRegionBox *extents;
|
||
int numRects;
|
||
|
||
extents = ®->extents;
|
||
|
||
numRects = ((numFullPtBlocks * NUMPTSTOBUFFER) + iCurPtBlock) >> 1;
|
||
|
||
GROWREGION(reg, numRects);
|
||
|
||
CurPtBlock = FirstPtBlock;
|
||
rects = reg->rects - 1;
|
||
numRects = 0;
|
||
extents->x1 = G_MAXSHORT, extents->x2 = G_MINSHORT;
|
||
|
||
for ( ; numFullPtBlocks >= 0; numFullPtBlocks--) {
|
||
/* the loop uses 2 points per iteration */
|
||
i = NUMPTSTOBUFFER >> 1;
|
||
if (!numFullPtBlocks)
|
||
i = iCurPtBlock >> 1;
|
||
for (pts = CurPtBlock->pts; i--; pts += 2) {
|
||
if (pts->x == pts[1].x)
|
||
continue;
|
||
if (numRects && pts->x == rects->x1 && pts->y == rects->y2 &&
|
||
pts[1].x == rects->x2 &&
|
||
(numRects == 1 || rects[-1].y1 != rects->y1) &&
|
||
(i && pts[2].y > pts[1].y)) {
|
||
rects->y2 = pts[1].y + 1;
|
||
continue;
|
||
}
|
||
numRects++;
|
||
rects++;
|
||
rects->x1 = pts->x; rects->y1 = pts->y;
|
||
rects->x2 = pts[1].x; rects->y2 = pts[1].y + 1;
|
||
if (rects->x1 < extents->x1)
|
||
extents->x1 = rects->x1;
|
||
if (rects->x2 > extents->x2)
|
||
extents->x2 = rects->x2;
|
||
}
|
||
CurPtBlock = CurPtBlock->next;
|
||
}
|
||
|
||
if (numRects) {
|
||
extents->y1 = reg->rects->y1;
|
||
extents->y2 = rects->y2;
|
||
} else {
|
||
extents->x1 = 0;
|
||
extents->y1 = 0;
|
||
extents->x2 = 0;
|
||
extents->y2 = 0;
|
||
}
|
||
reg->numRects = numRects;
|
||
|
||
return(TRUE);
|
||
}
|
||
|
||
/**
|
||
* gdk_region_polygon:
|
||
* @points: an array of #GdkPoint structs
|
||
* @n_points: the number of elements in the @points array
|
||
* @fill_rule: specifies which pixels are included in the region when the
|
||
* polygon overlaps itself.
|
||
*
|
||
* Creates a new #GdkRegion using the polygon defined by a
|
||
* number of points.
|
||
*
|
||
* Returns: a new #GdkRegion based on the given polygon
|
||
*
|
||
* Deprecated: 2.22: There is no replacement. For working with paths, please
|
||
* use Cairo.
|
||
*/
|
||
GdkRegion *
|
||
gdk_region_polygon (const GdkPoint *points,
|
||
gint n_points,
|
||
GdkFillRule fill_rule)
|
||
{
|
||
GdkRegion *region;
|
||
EdgeTableEntry *pAET; /* Active Edge Table */
|
||
int y; /* current scanline */
|
||
int iPts = 0; /* number of pts in buffer */
|
||
EdgeTableEntry *pWETE; /* Winding Edge Table Entry*/
|
||
ScanLineList *pSLL; /* current scanLineList */
|
||
GdkPoint *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;
|
||
|
||
region = gdk_region_new ();
|
||
|
||
/* special case a rectangle */
|
||
if (((n_points == 4) ||
|
||
((n_points == 5) && (points[4].x == points[0].x) && (points[4].y == points[0].y))) &&
|
||
(((points[0].y == points[1].y) &&
|
||
(points[1].x == points[2].x) &&
|
||
(points[2].y == points[3].y) &&
|
||
(points[3].x == points[0].x)) ||
|
||
((points[0].x == points[1].x) &&
|
||
(points[1].y == points[2].y) &&
|
||
(points[2].x == points[3].x) &&
|
||
(points[3].y == points[0].y)))) {
|
||
region->extents.x1 = MIN(points[0].x, points[2].x);
|
||
region->extents.y1 = MIN(points[0].y, points[2].y);
|
||
region->extents.x2 = MAX(points[0].x, points[2].x);
|
||
region->extents.y2 = MAX(points[0].y, points[2].y);
|
||
if ((region->extents.x1 != region->extents.x2) &&
|
||
(region->extents.y1 != region->extents.y2)) {
|
||
region->numRects = 1;
|
||
*(region->rects) = region->extents;
|
||
}
|
||
return(region);
|
||
}
|
||
|
||
pETEs = g_new (EdgeTableEntry, n_points);
|
||
|
||
pts = FirstPtBlock.pts;
|
||
CreateETandAET(n_points, points, &ET, &AET, pETEs, &SLLBlock);
|
||
pSLL = ET.scanlines.next;
|
||
curPtBlock = &FirstPtBlock;
|
||
|
||
if (fill_rule == GDK_EVEN_ODD_RULE) {
|
||
/*
|
||
* 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 = (POINTBLOCK *)g_malloc(sizeof(POINTBLOCK));
|
||
tmpPtBlock->next = NULL;
|
||
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 = (POINTBLOCK *)g_malloc(sizeof(POINTBLOCK));
|
||
tmpPtBlock->next = NULL;
|
||
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;
|
||
g_free (curPtBlock);
|
||
curPtBlock = tmpPtBlock;
|
||
}
|
||
g_free (pETEs);
|
||
return(region);
|
||
}
|
||
|
||
#define __GDK_POLYREG_GENERIC_C__
|
||
#include "gdkaliasdef.c"
|