~chasedouglas/ubuntu/maverick/xorg-server/multitouch : contents of mi/mipoly.h at revision 192

~chasedouglas/ubuntu/maverick/xorg-server/multitouch : (revision 192)

/*

Copyright 1987, 1998  The Open Group

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

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.

*/


/*
 *     fill.h
 *
 *     Created by Brian Kelleher; Oct 1985
 *
 *     Include file for filled polygon routines.
 *
 *     These are the data structures needed to scan
 *     convert regions.  Two different scan conversion
 *     methods are available -- the even-odd method, and
 *     the winding number method.
 *     The even-odd rule states that a point is inside
 *     the polygon if a ray drawn from that point in any
 *     direction will pass through an odd number of
 *     path segments.
 *     By the winding number rule, a point is decided
 *     to be inside the polygon if a ray drawn from that
 *     point in any direction passes through a different
 *     number of clockwise and counter-clockwise path
 *     segments.
 *
 *     These data structures are adapted somewhat from
 *     the algorithm in (Foley/Van Dam) for scan converting
 *     polygons.
 *     The basic algorithm is to start at the top (smallest y)
 *     of the polygon, stepping down to the bottom of
 *     the polygon by incrementing the y coordinate.  We
 *     keep a list of edges which the current scanline crosses,
 *     sorted by x.  This list is called the Active Edge Table (AET)
 *     As we change the y-coordinate, we update each entry in 
 *     in the active edge table to reflect the edges new xcoord.
 *     This list must be sorted at each scanline in case
 *     two edges intersect.
 *     We also keep a data structure known as the Edge Table (ET),
 *     which keeps track of all the edges which the current
 *     scanline has not yet reached.  The ET is basically a
 *     list of ScanLineList structures containing a list of
 *     edges which are entered at a given scanline.  There is one
 *     ScanLineList per scanline at which an edge is entered.
 *     When we enter a new edge, we move it from the ET to the AET.
 *
 *     From the AET, we can implement the even-odd rule as in
 *     (Foley/Van Dam).
 *     The winding number rule is a little trickier.  We also
 *     keep the EdgeTableEntries in the AET linked by the
 *     nextWETE (winding EdgeTableEntry) link.  This allows
 *     the edges to be linked just as before for updating
 *     purposes, but only uses the edges linked by the nextWETE
 *     link as edges representing spans of the polygon to
 *     drawn (as with the even-odd rule).
 */

/*
 * for the winding number rule
 */
#define CLOCKWISE          1
#define COUNTERCLOCKWISE  -1 

typedef struct _EdgeTableEntry {
     int ymax;             /* ycoord at which we exit this edge. */
     BRESINFO bres;        /* Bresenham info to run the edge     */
     struct _EdgeTableEntry *next;       /* next in the list     */
     struct _EdgeTableEntry *back;       /* for insertion sort   */
     struct _EdgeTableEntry *nextWETE;   /* for winding num rule */
     int ClockWise;        /* flag for winding number rule       */
} EdgeTableEntry;


typedef struct _ScanLineList{
     int scanline;              /* the scanline represented */
     EdgeTableEntry *edgelist;  /* header node              */
     struct _ScanLineList *next;  /* next in the list       */
} ScanLineList;


typedef struct {
     int ymax;                 /* ymax for the polygon     */
     int ymin;                 /* ymin for the polygon     */
     ScanLineList scanlines;   /* header node              */
} EdgeTable;


/*
 * Here is a struct to help with storage allocation
 * so we can allocate a big chunk at a time, and then take
 * pieces from this heap when we need to.
 */
#define SLLSPERBLOCK 25

typedef struct _ScanLineListBlock {
     ScanLineList SLLs[SLLSPERBLOCK];
     struct _ScanLineListBlock *next;
} ScanLineListBlock;

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


/*
 *
 *     a few macros for the inner loops of the fill code where
 *     performance considerations don't allow a procedure call.
 *
 *     Evaluate the given edge at the given scanline.
 *     If the edge has expired, then we leave it and fix up
 *     the active edge table; otherwise, we increment the
 *     x value to be ready for the next scanline.
 *     The winding number rule is in effect, so we must notify
 *     the caller when the edge has been removed so he
 *     can reorder the Winding Active Edge Table.
 */
#define EVALUATEEDGEWINDING(pAET, pPrevAET, y, fixWAET) { \
   if (pAET->ymax == y) {          /* leaving this edge */ \
      pPrevAET->next = pAET->next; \
      pAET = pPrevAET->next; \
      fixWAET = 1; \
      if (pAET) \
         pAET->back = pPrevAET; \
   } \
   else { \
      BRESINCRPGONSTRUCT(pAET->bres); \
      pPrevAET = pAET; \
      pAET = pAET->next; \
   } \
}


/*
 *     Evaluate the given edge at the given scanline.
 *     If the edge has expired, then we leave it and fix up
 *     the active edge table; otherwise, we increment the
 *     x value to be ready for the next scanline.
 *     The even-odd rule is in effect.
 */
#define EVALUATEEDGEEVENODD(pAET, pPrevAET, y) { \
   if (pAET->ymax == y) {          /* leaving this edge */ \
      pPrevAET->next = pAET->next; \
      pAET = pPrevAET->next; \
      if (pAET) \
         pAET->back = pPrevAET; \
   } \
   else { \
      BRESINCRPGONSTRUCT(pAET->bres); \
      pPrevAET = pAET; \
      pAET = pAET->next; \
   } \
}

/* mipolyutil.c */

extern _X_EXPORT Bool miCreateETandAET(
    int /*count*/,
    DDXPointPtr /*pts*/,
    EdgeTable * /*ET*/,
    EdgeTableEntry * /*AET*/,
    EdgeTableEntry * /*pETEs*/,
    ScanLineListBlock * /*pSLLBlock*/
);

extern _X_EXPORT void miloadAET(
    EdgeTableEntry * /*AET*/,
    EdgeTableEntry * /*ETEs*/
);

extern _X_EXPORT void micomputeWAET(
    EdgeTableEntry * /*AET*/
);

extern _X_EXPORT int miInsertionSort(
    EdgeTableEntry * /*AET*/
);

extern _X_EXPORT void miFreeStorage(
    ScanLineListBlock * /*pSLLBlock*/
);

1 by Daniel Stone Import upstream version 0.99.3	1	/*
	2
	3	Copyright 1987, 1998 The Open Group
	4
	5	Permission to use, copy, modify, distribute, and sell this software and its
	6	documentation for any purpose is hereby granted without fee, provided that
	7	the above copyright notice appear in all copies and that both that
	8	copyright notice and this permission notice appear in supporting
	9	documentation.
	10
	11	The above copyright notice and this permission notice shall be included
	12	in all copies or substantial portions of the Software.
	13
	14	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	15	OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	16	MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	17	IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
	18	OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	19	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	20	OTHER DEALINGS IN THE SOFTWARE.
	21
	22	Except as contained in this notice, the name of The Open Group shall
	23	not be used in advertising or otherwise to promote the sale, use or
	24	other dealings in this Software without prior written authorization
	25	from The Open Group.
	26
	27	*/
	28
	29
	30	/*
	31	* fill.h
	32	*
	33	* Created by Brian Kelleher; Oct 1985
	34	*
	35	* Include file for filled polygon routines.
	36	*
	37	* These are the data structures needed to scan
	38	* convert regions. Two different scan conversion
	39	* methods are available -- the even-odd method, and
	40	* the winding number method.
	41	* The even-odd rule states that a point is inside
	42	* the polygon if a ray drawn from that point in any
	43	* direction will pass through an odd number of
	44	* path segments.
	45	* By the winding number rule, a point is decided
	46	* to be inside the polygon if a ray drawn from that
	47	* point in any direction passes through a different
	48	* number of clockwise and counter-clockwise path
	49	* segments.
	50	*
	51	* These data structures are adapted somewhat from
	52	* the algorithm in (Foley/Van Dam) for scan converting
	53	* polygons.
	54	* The basic algorithm is to start at the top (smallest y)
	55	* of the polygon, stepping down to the bottom of
	56	* the polygon by incrementing the y coordinate. We
	57	* keep a list of edges which the current scanline crosses,
	58	* sorted by x. This list is called the Active Edge Table (AET)
	59	* As we change the y-coordinate, we update each entry in
	60	* in the active edge table to reflect the edges new xcoord.
	61	* This list must be sorted at each scanline in case
	62	* two edges intersect.
	63	* We also keep a data structure known as the Edge Table (ET),
	64	* which keeps track of all the edges which the current
65	* scanline has not yet reached. The ET is basically a
66	* list of ScanLineList structures containing a list of
67	* edges which are entered at a given scanline. There is one
68	* ScanLineList per scanline at which an edge is entered.
69	* When we enter a new edge, we move it from the ET to the AET.
70	*
71	* From the AET, we can implement the even-odd rule as in
72	* (Foley/Van Dam).
73	* The winding number rule is a little trickier. We also
74	* keep the EdgeTableEntries in the AET linked by the
75	* nextWETE (winding EdgeTableEntry) link. This allows
76	* the edges to be linked just as before for updating
77	* purposes, but only uses the edges linked by the nextWETE
78	* link as edges representing spans of the polygon to
79	* drawn (as with the even-odd rule).
80	*/
81
82	/*
83	* for the winding number rule
84	*/
85	#define CLOCKWISE 1
86	#define COUNTERCLOCKWISE -1
87
88	typedef struct _EdgeTableEntry {
89	int ymax; /* ycoord at which we exit this edge. */
90	BRESINFO bres; /* Bresenham info to run the edge */
91	struct _EdgeTableEntry next; / next in the list */
92	struct _EdgeTableEntry back; / for insertion sort */
93	struct _EdgeTableEntry nextWETE; / for winding num rule */
94	int ClockWise; /* flag for winding number rule */
95	} EdgeTableEntry;
96
97
98	typedef struct _ScanLineList{
99	int scanline; /* the scanline represented */
100	EdgeTableEntry edgelist; / header node */
101	struct _ScanLineList next; / next in the list */
102	} ScanLineList;
103
104
105	typedef struct {
106	int ymax; /* ymax for the polygon */
107	int ymin; /* ymin for the polygon */
108	ScanLineList scanlines; /* header node */
109	} EdgeTable;
110
111
112	/*
113	* Here is a struct to help with storage allocation
114	* so we can allocate a big chunk at a time, and then take
115	* pieces from this heap when we need to.
116	*/
117	#define SLLSPERBLOCK 25
118
119	typedef struct _ScanLineListBlock {
120	ScanLineList SLLs[SLLSPERBLOCK];
121	struct _ScanLineListBlock *next;
122	} ScanLineListBlock;
123
124	/*
125	* number of points to buffer before sending them off
126	* to scanlines() : Must be an even number
127	*/
128	#define NUMPTSTOBUFFER 200
129
130
131	/*
132	*
133	* a few macros for the inner loops of the fill code where
134	* performance considerations don't allow a procedure call.
135	*
136	* Evaluate the given edge at the given scanline.
137	* If the edge has expired, then we leave it and fix up
138	* the active edge table; otherwise, we increment the
139	* x value to be ready for the next scanline.
140	* The winding number rule is in effect, so we must notify
141	* the caller when the edge has been removed so he
142	* can reorder the Winding Active Edge Table.
143	*/
144	#define EVALUATEEDGEWINDING(pAET, pPrevAET, y, fixWAET) { \
145	if (pAET->ymax == y) { /* leaving this edge */ \
146	pPrevAET->next = pAET->next; \
147	pAET = pPrevAET->next; \
148	fixWAET = 1; \
149	if (pAET) \
150	pAET->back = pPrevAET; \
151	} \
152	else { \
153	BRESINCRPGONSTRUCT(pAET->bres); \
154	pPrevAET = pAET; \
155	pAET = pAET->next; \
156	} \
157	}
158
159
160	/*
161	* Evaluate the given edge at the given scanline.
162	* If the edge has expired, then we leave it and fix up
163	* the active edge table; otherwise, we increment the
164	* x value to be ready for the next scanline.
165	* The even-odd rule is in effect.
166	*/
167	#define EVALUATEEDGEEVENODD(pAET, pPrevAET, y) { \
168	if (pAET->ymax == y) { /* leaving this edge */ \
169	pPrevAET->next = pAET->next; \
170	pAET = pPrevAET->next; \
171	if (pAET) \
172	pAET->back = pPrevAET; \
173	} \
174	else { \
175	BRESINCRPGONSTRUCT(pAET->bres); \
176	pPrevAET = pAET; \
177	pAET = pAET->next; \
178	} \
179	}
180
181	/* mipolyutil.c */
182
0.8.1 by Julien Cristau Import upstream version 1.6.99.903	183	extern _X_EXPORT Bool miCreateETandAET(
1 by Daniel Stone Import upstream version 0.99.3	184	int /count/,
	185	DDXPointPtr /pts/,
	186	EdgeTable * /ET/,
	187	EdgeTableEntry * /AET/,
	188	EdgeTableEntry * /pETEs/,
	189	ScanLineListBlock * /pSLLBlock/
	190	);
	191
0.8.1 by Julien Cristau Import upstream version 1.6.99.903	192	extern _X_EXPORT void miloadAET(
1 by Daniel Stone Import upstream version 0.99.3	193	EdgeTableEntry * /AET/,
	194	EdgeTableEntry * /ETEs/
	195	);
	196
0.8.1 by Julien Cristau Import upstream version 1.6.99.903	197	extern _X_EXPORT void micomputeWAET(
	198	EdgeTableEntry * /AET/
	199	);
	200
	201	extern _X_EXPORT int miInsertionSort(
	202	EdgeTableEntry * /AET/
	203	);
	204
	205	extern _X_EXPORT void miFreeStorage(
1 by Daniel Stone Import upstream version 0.99.3	206	ScanLineListBlock * /pSLLBlock/
1 by Daniel Stone Import upstream version 0.99.3	207	);