/* $XConsortium: region.h,v 11.13 91/09/10 08:21:49 rws Exp $ */
/************************************************************************
Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts,
and the Massachusetts Institute of Technology, Cambridge, 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 names of Digital or MIT 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.

************************************************************************/

#ifndef _XREGION_H
#define _XREGION_H

typedef struct {
    short x1, x2, y1, y2;
} Box, BOX, BoxRec, *BoxPtr;

typedef struct {
    short x, y, width, height;
}RECTANGLE, RectangleRec, *RectanglePtr;

#define TRUE 1
#define FALSE 0
#define MAXSHORT 32767
#define MINSHORT -MAXSHORT
#ifndef MAX
#define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
#ifndef MIN
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif


/* 
 *   clip region
 */

typedef struct _XRegion {
    long size;
    long numRects;
    BOX *rects;
    BOX extents;
} REGION;

/* Xutil.h contains the declaration: 
 * typedef struct _XRegion *Region; 
 */   

/*  1 if two BOXs overlap.
 *  0 if two BOXs do not overlap.
 *  Remember, x2 and y2 are not in the region 
 */
#define EXTENTCHECK(r1, r2) \
	((r1)->x2 > (r2)->x1 && \
	 (r1)->x1 < (r2)->x2 && \
	 (r1)->y2 > (r2)->y1 && \
	 (r1)->y1 < (r2)->y2)

/*
 *  update region extents
 */
#define EXTENTS(r,idRect){\
            if((r)->x1 < (idRect)->extents.x1)\
              (idRect)->extents.x1 = (r)->x1;\
            if((r)->y1 < (idRect)->extents.y1)\
              (idRect)->extents.y1 = (r)->y1;\
            if((r)->x2 > (idRect)->extents.x2)\
              (idRect)->extents.x2 = (r)->x2;\
            if((r)->y2 > (idRect)->extents.y2)\
              (idRect)->extents.y2 = (r)->y2;\
        }

/*
 *   Check to see if there is enough memory in the present region.
 */
#define MEMCHECK(reg, rect, firstrect){\
        if ((reg)->numRects >= ((reg)->size - 1)){\
          (firstrect) = (BOX *) Xrealloc \
          ((char *)(firstrect), (unsigned) (2 * (sizeof(BOX)) * ((reg)->size)));\
          if ((firstrect) == 0)\
            return(0);\
          (reg)->size *= 2;\
          (rect) = &(firstrect)[(reg)->numRects];\
         }\
       }

/*  this routine checks to see if the previous rectangle is the same
 *  or subsumes the new rectangle to add.
 */

#define CHECK_PREVIOUS(Reg, R, Rx1, Ry1, Rx2, Ry2)\
               (!(((Reg)->numRects > 0)&&\
                  ((R-1)->y1 == (Ry1)) &&\
                  ((R-1)->y2 == (Ry2)) &&\
                  ((R-1)->x1 <= (Rx1)) &&\
                  ((R-1)->x2 >= (Rx2))))

/*  add a rectangle to the given Region */
#define ADDRECT(reg, r, rx1, ry1, rx2, ry2){\
    if (((rx1) < (rx2)) && ((ry1) < (ry2)) &&\
        CHECK_PREVIOUS((reg), (r), (rx1), (ry1), (rx2), (ry2))){\
              (r)->x1 = (rx1);\
              (r)->y1 = (ry1);\
              (r)->x2 = (rx2);\
              (r)->y2 = (ry2);\
              EXTENTS((r), (reg));\
              (reg)->numRects++;\
              (r)++;\
            }\
        }



/*  add a rectangle to the given Region */
#define ADDRECTNOX(reg, r, rx1, ry1, rx2, ry2){\
            if ((rx1 < rx2) && (ry1 < ry2) &&\
                CHECK_PREVIOUS((reg), (r), (rx1), (ry1), (rx2), (ry2))){\
              (r)->x1 = (rx1);\
              (r)->y1 = (ry1);\
              (r)->x2 = (rx2);\
              (r)->y2 = (ry2);\
              (reg)->numRects++;\
              (r)++;\
            }\
        }

#define EMPTY_REGION(pReg) pReg->numRects = 0

#define REGION_NOT_EMPTY(pReg) pReg->numRects

#define INBOX(r, x, y) \
      ( ( ((r).x2 >  x)) && \
        ( ((r).x1 <= x)) && \
        ( ((r).y2 >  y)) && \
        ( ((r).y1 <= y)) )

/*
 * number of points to buffer before sending them off
 * to scanlines() :  Must be an even number
 */
#define NUMPTSTOBUFFER 200

/*
 * used to allocate buffers for points and link
 * the buffers together
 */
typedef struct _POINTBLOCK {
    XPoint pts[NUMPTSTOBUFFER];
    struct _POINTBLOCK *next;
} POINTBLOCK;

#endif
