src/rt/rview.c

/* Copyright (c) 1987 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  rview.c - routines and variables for interactive view generation.
 *
 *     3/24/87
 */

#include  "ray.h"

#include  "rpaint.h"

#include  <signal.h>

#include  <ctype.h>

VIEW  ourview = STDVIEW;                /* viewing parameters */
int  hresolu, vresolu;                  /* image resolution */

int  dimlist[MAXDIM];                   /* sampling dimensions */
int  ndims = 0;                         /* number of sampling dimensions */
int  samplendx = 0;                     /* index for this sample */

int  psample = 8;                       /* pixel sample size */
double  maxdiff = .15;                  /* max. sample difference */

double  exposure = 1.0;                 /* exposure for scene */

double  dstrsrc = 0.0;                  /* square source distribution */
double  shadthresh = .1;                /* shadow threshold */
double  shadcert = .25;                 /* shadow certainty */
int  directrelay = 0;                   /* number of source relays */
int  vspretest = 128;                   /* virtual source pretest density */

int  maxdepth = 4;                      /* maximum recursion depth */
double  minweight = 1e-2;               /* minimum ray weight */

COLOR  ambval = BLKCOLOR;               /* ambient value */
double  ambacc = 0.2;                   /* ambient accuracy */
int  ambres = 8;                        /* ambient resolution */
int  ambdiv = 32;                       /* ambient divisions */
int  ambssamp = 0;                      /* ambient super-samples */
int  ambounce = 0;                      /* ambient bounces */
char  *amblist[128];                    /* ambient include/exclude list */
int  ambincl = -1;                      /* include == 1, exclude == 0 */

int  greyscale = 0;                     /* map colors to brightness? */
char  *devname = dev_default;           /* output device name */

struct driver  *dev = NULL;             /* driver functions */

VIEW  oldview;                          /* previous view parameters */

PNODE  ptrunk;                          /* the base of our image */
RECT  pframe;                           /* current frame boundaries */
int  pdepth;                            /* image depth in current frame */

static char  *reserve_mem = NULL;       /* pre-allocated reserve memory */

#define RESERVE_AMT     8192            /* amount of memory to reserve */

#define  CTRL(c)        ('c'-'@')


quit(code)                      /* quit program */
int  code;
{
        devclose();
        exit(code);
}


devopen(dname)                          /* open device driver */
char  *dname;
{
        extern char  *progname, *octname;
        char  *id;
        register int  i;

        id = octname!=NULL ? octname : progname;
                                                /* check device table */
        for (i = 0; devtable[i].name; i++)
                if (!strcmp(dname, devtable[i].name))
                        if ((dev = (*devtable[i].init)(dname, id)) == NULL) {
                                sprintf(errmsg, "cannot initialize %s", dname);
                                error(USER, errmsg);
                        } else
                                return;
                                                /* not there, try exec */
        if ((dev = comm_init(dname, id)) == NULL) {
                sprintf(errmsg, "cannot start device \"%s\"", dname);
                error(USER, errmsg);
        }
}


devclose()                              /* close our device */
{
        if (dev != NULL)
                (*dev->close)();
        dev = NULL;
}


printdevices()                          /* print list of output devices */
{
        register int  i;

        for (i = 0; devtable[i].name; i++)
                printf("%-16s # %s\n", devtable[i].name, devtable[i].descrip);
}


rview()                         /* do a view */
{
        char  buf[32];

        devopen(devname);               /* open device */
        newimage();                     /* start image (calls fillreserves) */

        for ( ; ; ) {                   /* quit in command() */
                while (hresolu <= 1<<pdepth && vresolu <= 1<<pdepth)
                        command("done: ");
                while (reserve_mem == NULL)
                        command("out of memory: ");
                errno = 0;
                if (hresolu <= psample<<pdepth && vresolu <= psample<<pdepth) {
                        sprintf(buf, "%d sampling...\n", 1<<pdepth);
                        (*dev->comout)(buf);
                        rsample();
                } else {
                        sprintf(buf, "%d refining...\n", 1<<pdepth);
                        (*dev->comout)(buf);
                        refine(&ptrunk, 0, 0, hresolu, vresolu, pdepth+1);
                }
                if (errno == ENOMEM)            /* ran out of memory */
                        freereserves();
                else if (dev->inpready)         /* noticed some input */
                        command(": ");
                else                            /* finished this depth */
                        pdepth++;
        }
}


fillreserves()                  /* fill memory reserves */
{
        if (reserve_mem != NULL)
                return;
        reserve_mem = malloc(RESERVE_AMT);
}


freereserves()                  /* free memory reserves */
{
        if (reserve_mem == NULL)
                return;
        free(reserve_mem);
        reserve_mem = NULL;
}


command(prompt)                 /* get/execute command */
char  *prompt;
{
#define  badcom(s)      strncmp(s, inpbuf, args-inpbuf-1)
        double  atof();
        char  inpbuf[256];
        char  *args;
again:
        (*dev->comin)(inpbuf, prompt);          /* get command + arguments */
        for (args = inpbuf; *args && *args != ' '; args++)
                ;
        if (*args) *args++ = '\0';
        else *++args = '\0';
        
        switch (inpbuf[0]) {
        case 'f':                               /* new frame */
                if (badcom("frame"))
                        goto commerr;
                getframe(args);
                break;
        case 'v':                               /* view */
                if (badcom("view"))
                        goto commerr;
                getview(args);
                break;
        case 'l':                               /* last view */
                if (badcom("last"))
                        goto commerr;
                lastview(args);
                break;
        case 'e':                               /* exposure */
                if (badcom("exposure"))
                        goto commerr;
                getexposure(args);
                break;
        case 's':                               /* set a parameter */
                if (badcom("set"))
                        goto commerr;
                setparam(args);
                break;
        case 'n':                               /* new picture */
                if (badcom("new"))
                        goto commerr;
                newimage();
                break;
        case 't':                               /* trace a ray */
                if (badcom("trace"))
                        goto commerr;
                traceray(args);
                break;
        case 'a':                               /* aim camera */
                if (badcom("aim"))
                        goto commerr;
                getaim(args);
                break;
        case 'm':                               /* move camera */
                if (badcom("move"))
                        goto commerr;
                getmove(args);
                break;
        case 'r':                               /* rotate/repaint */
                if (badcom("rotate")) {
                        if (badcom("repaint"))
                                goto commerr;
                        getrepaint(args);
                        break;
                }
                getrotate(args);
                break;
        case 'p':                               /* pivot view */
                if (badcom("pivot"))
                        goto commerr;
                getpivot(args);
                break;
        case CTRL(R):                           /* redraw */
                redraw();
                break;
        case 'w':                               /* write */
                if (badcom("write"))
                        goto commerr;
                writepict(args);
                break;
        case 'q':                               /* quit */
                if (badcom("quit"))
                        goto commerr;
                quit(0);
        case CTRL(C):                           /* interrupt */
                goto again;
#ifdef  SIGTSTP
        case CTRL(Z):                           /* stop */
                devclose();
                kill(0, SIGTSTP);
                /* pc stops here */
                devopen(devname);
                redraw();
                break;
#endif
        case '\0':                              /* continue */
                break;
        default:;
commerr:
                if (iscntrl(inpbuf[0]))
                        sprintf(errmsg, "^%c: unknown control",
                                        inpbuf[0]|0100);
                else
                        sprintf(errmsg, "%s: unknown command", inpbuf);
                error(COMMAND, errmsg);
                break;
        }
#undef  badcom
}


rsample()                       /* sample the image */
{
        int  xsiz, ysiz, y;
        RECT  r;
        PNODE  *p;
        register RECT  *rl;
        register PNODE  **pl;
        register int  x;
        /*
         *     We initialize the bottom row in the image at our current
         * resolution.  During sampling, we check super-pixels to the
         * right and above by calling bigdiff().  If there is a significant
         * difference, we subsample the super-pixels.  The testing process
         * includes initialization of the next row.
         */
        xsiz = (((pframe.r-pframe.l)<<pdepth)+hresolu-1) / hresolu;
        ysiz = (((pframe.u-pframe.d)<<pdepth)+vresolu-1) / vresolu;
        rl = (RECT *)malloc(xsiz*sizeof(RECT));
        if (rl == NULL)
                return;
        pl = (PNODE **)malloc(xsiz*sizeof(PNODE *));
        if (pl == NULL)
                return;
        /*
         * Initialize the bottom row.
         */
        rl[0].l = rl[0].d = 0;
        rl[0].r = hresolu; rl[0].u = vresolu;
        pl[0] = findrect(pframe.l, pframe.d, &ptrunk, rl, pdepth);
        for (x = 1; x < xsiz; x++) {
                rl[x].l = rl[x].d = 0;
                rl[x].r = hresolu; rl[x].u = vresolu;
                pl[x] = findrect(pframe.l+((x*hresolu)>>pdepth),
                                pframe.d, &ptrunk, rl+x, pdepth);
        }
                                                /* sample the image */
        for (y = 0; /* y < ysiz */ ; y++) {
                for (x = 0; x < xsiz-1; x++) {
                        if (dev->inpready)
                                goto escape;
                        /*
                         * Test super-pixel to the right.
                         */
                        if (pl[x] != pl[x+1] && bigdiff(pl[x]->v,
                                        pl[x+1]->v, maxdiff)) {
                                refine(pl[x], rl[x].l, rl[x].d,
                                                rl[x].r, rl[x].u, 1);
                                refine(pl[x+1], rl[x+1].l, rl[x+1].d,
                                                rl[x+1].r, rl[x+1].u, 1);
                        }
                }
                if (y >= ysiz-1)
                        break;
                for (x = 0; x < xsiz; x++) {
                        if (dev->inpready)
                                goto escape;
                        /*
                         * Find super-pixel at this position in next row.
                         */
                        r.l = r.d = 0;
                        r.r = hresolu; r.u = vresolu;
                        p = findrect(pframe.l+((x*hresolu)>>pdepth),
                                pframe.d+(((y+1)*vresolu)>>pdepth),
                                        &ptrunk, &r, pdepth);
                        /*
                         * Test super-pixel in next row.
                         */
                        if (pl[x] != p && bigdiff(pl[x]->v, p->v, maxdiff)) {
                                refine(pl[x], rl[x].l, rl[x].d,
                                                rl[x].r, rl[x].u, 1);
                                refine(p, r.l, r.d, r.r, r.u, 1);
                        }
                        /*
                         * Copy into super-pixel array.
                         */
                        rl[x].l = r.l; rl[x].d = r.d;
                        rl[x].r = r.r; rl[x].u = r.u;
                        pl[x] = p;
                }
        }
escape:
        free((char *)rl);
        free((char *)pl);
}


int
refine(p, xmin, ymin, xmax, ymax, pd)           /* refine a node */
register PNODE  *p;
int  xmin, ymin, xmax, ymax;
int  pd;
{
        int  growth;
        int  mx, my;
        int  i;

        if (dev->inpready)                      /* quit for input */
                return(0);

        if (pd <= 0)                            /* depth limit */
                return(0);

        mx = (xmin + xmax) >> 1;
        my = (ymin + ymax) >> 1;
        growth = 0;

        if (p->kid == NULL) {                   /* subdivide */

                if ((p->kid = newptree()) == NULL)
                        return(growth);
                /*
                 *  The following paint order can leave a black pixel
                 *  when redraw() is called in (*dev->paintr)().
                 */
                if (p->x >= mx && p->y >= my)
                        pcopy(p, p->kid+UR);
                else
                        paint(p->kid+UR, mx, my, xmax, ymax);
                if (p->x < mx && p->y >= my)
                        pcopy(p, p->kid+UL);
                else
                        paint(p->kid+UL, xmin, my, mx, ymax);
                if (p->x >= mx && p->y < my)
                        pcopy(p, p->kid+DR);
                else
                        paint(p->kid+DR, mx, ymin, xmax, my);
                if (p->x < mx && p->y < my)
                        pcopy(p, p->kid+DL);
                else
                        paint(p->kid+DL, xmin, ymin, mx, my);

                growth++;
        }
                                                /* do children */
        if (mx > pframe.l) {
                if (my > pframe.d)
                        growth += refine(p->kid+DL, xmin, ymin, mx, my, pd-1);
                if (my < pframe.u)
                        growth += refine(p->kid+UL, xmin, my, mx, ymax, pd-1);
        }
        if (mx < pframe.r) {
                if (my > pframe.d)
                        growth += refine(p->kid+DR, mx, ymin, xmax, my, pd-1);
                if (my < pframe.u)
                        growth += refine(p->kid+UR, mx, my, xmax, ymax, pd-1);
        }
                                                /* recompute sum */
        if (growth) {
                setcolor(p->v, 0.0, 0.0, 0.0);
                for (i = 0; i < 4; i++)
                        addcolor(p->v, p->kid[i].v);
                scalecolor(p->v, 0.25);
        }
        return(growth);
}
Revision:	1.18
Committed:	Tue Jun 25 14:06:15 1991 UTC (32 years, 10 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.17:	+1 -1 lines
Log Message:	increased defaults for -dp parameter
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1987 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* rview.c - routines and variables for interactive view generation.
9			*
10			* 3/24/87
11			*/
12
13	greg	1.15	#include "ray.h"
14	greg	1.1
15			#include "rpaint.h"
16
17			#include <signal.h>
18
19			#include <ctype.h>
20
21	greg	1.9	VIEW ourview = STDVIEW; /* viewing parameters */
22			int hresolu, vresolu; /* image resolution */
23	greg	1.15
24			int dimlist[MAXDIM]; /* sampling dimensions */
25			int ndims = 0; /* number of sampling dimensions */
26			int samplendx = 0; /* index for this sample */
27	greg	1.1
28			int psample = 8; /* pixel sample size */
29			double maxdiff = .15; /* max. sample difference */
30
31			double exposure = 1.0; /* exposure for scene */
32
33			double dstrsrc = 0.0; /* square source distribution */
34	greg	1.3	double shadthresh = .1; /* shadow threshold */
35	greg	1.4	double shadcert = .25; /* shadow certainty */
36	greg	1.16	int directrelay = 0; /* number of source relays */
37	greg	1.18	int vspretest = 128; /* virtual source pretest density */
38	greg	1.1
39			int maxdepth = 4; /* maximum recursion depth */
40			double minweight = 1e-2; /* minimum ray weight */
41
42			COLOR ambval = BLKCOLOR; /* ambient value */
43			double ambacc = 0.2; /* ambient accuracy */
44	greg	1.5	int ambres = 8; /* ambient resolution */
45	greg	1.1	int ambdiv = 32; /* ambient divisions */
46			int ambssamp = 0; /* ambient super-samples */
47			int ambounce = 0; /* ambient bounces */
48			char amblist[128]; / ambient include/exclude list */
49			int ambincl = -1; /* include == 1, exclude == 0 */
50
51			int greyscale = 0; /* map colors to brightness? */
52	greg	1.11	char devname = dev_default; / output device name */
53	greg	1.1
54			struct driver dev = NULL; / driver functions */
55
56			VIEW oldview; /* previous view parameters */
57
58			PNODE ptrunk; /* the base of our image */
59			RECT pframe; /* current frame boundaries */
60			int pdepth; /* image depth in current frame */
61
62	greg	1.12	static char reserve_mem = NULL; / pre-allocated reserve memory */
63
64			#define RESERVE_AMT 8192 /* amount of memory to reserve */
65
66	greg	1.1	#define CTRL(c) ('c'-'@')
67
68
69			quit(code) /* quit program */
70			int code;
71			{
72			devclose();
73			exit(code);
74			}
75
76
77			devopen(dname) /* open device driver */
78			char *dname;
79			{
80	greg	1.6	extern char progname, octname;
81	greg	1.7	char *id;
82	greg	1.1	register int i;
83	greg	1.6
84	greg	1.7	id = octname!=NULL ? octname : progname;
85	greg	1.1	/* check device table */
86			for (i = 0; devtable[i].name; i++)
87			if (!strcmp(dname, devtable[i].name))
88	greg	1.7	if ((dev = (*devtable[i].init)(dname, id)) == NULL) {
89	greg	1.1	sprintf(errmsg, "cannot initialize %s", dname);
90			error(USER, errmsg);
91			} else
92			return;
93			/* not there, try exec */
94	greg	1.7	if ((dev = comm_init(dname, id)) == NULL) {
95	greg	1.1	sprintf(errmsg, "cannot start device \"%s\"", dname);
96			error(USER, errmsg);
97			}
98			}
99
100
101			devclose() /* close our device */
102			{
103			if (dev != NULL)
104			(*dev->close)();
105			dev = NULL;
106			}
107
108
109			printdevices() /* print list of output devices */
110			{
111			register int i;
112
113			for (i = 0; devtable[i].name; i++)
114			printf("%-16s # %s\n", devtable[i].name, devtable[i].descrip);
115			}
116
117
118			rview() /* do a view */
119			{
120			char buf[32];
121
122			devopen(devname); /* open device */
123	greg	1.14	newimage(); /* start image (calls fillreserves) */
124
125	greg	1.1	for ( ; ; ) { /* quit in command() */
126	greg	1.14	while (hresolu <= 1<<pdepth && vresolu <= 1<<pdepth)
127	greg	1.1	command("done: ");
128	greg	1.14	while (reserve_mem == NULL)
129			command("out of memory: ");
130			errno = 0;
131			if (hresolu <= psample<<pdepth && vresolu <= psample<<pdepth) {
132	greg	1.1	sprintf(buf, "%d sampling...\n", 1<<pdepth);
133			(*dev->comout)(buf);
134			rsample();
135			} else {
136			sprintf(buf, "%d refining...\n", 1<<pdepth);
137			(*dev->comout)(buf);
138	greg	1.9	refine(&ptrunk, 0, 0, hresolu, vresolu, pdepth+1);
139	greg	1.1	}
140	greg	1.14	if (errno == ENOMEM) /* ran out of memory */
141			freereserves();
142			else if (dev->inpready) /* noticed some input */
143	greg	1.1	command(": ");
144	greg	1.14	else /* finished this depth */
145	greg	1.1	pdepth++;
146			}
147			}
148
149
150	greg	1.14	fillreserves() /* fill memory reserves */
151	greg	1.12	{
152			if (reserve_mem != NULL)
153	greg	1.14	return;
154	greg	1.12	reserve_mem = malloc(RESERVE_AMT);
155			}
156
157
158	greg	1.14	freereserves() /* free memory reserves */
159	greg	1.12	{
160	greg	1.14	if (reserve_mem == NULL)
161			return;
162	greg	1.12	free(reserve_mem);
163			reserve_mem = NULL;
164			}
165
166
167	greg	1.1	command(prompt) /* get/execute command */
168			char *prompt;
169			{
170			#define badcom(s) strncmp(s, inpbuf, args-inpbuf-1)
171			double atof();
172			char inpbuf[256];
173			char *args;
174			again:
175	greg	1.10	(dev->comin)(inpbuf, prompt); / get command + arguments */
176	greg	1.1	for (args = inpbuf; args && args != ' '; args++)
177			;
178			if (args) args++ = '\0';
179			else *++args = '\0';
180
181			switch (inpbuf[0]) {
182			case 'f': /* new frame */
183			if (badcom("frame"))
184			goto commerr;
185			getframe(args);
186			break;
187			case 'v': /* view */
188			if (badcom("view"))
189			goto commerr;
190			getview(args);
191			break;
192			case 'l': /* last view */
193			if (badcom("last"))
194			goto commerr;
195			lastview(args);
196			break;
197			case 'e': /* exposure */
198			if (badcom("exposure"))
199			goto commerr;
200			getexposure(args);
201			break;
202			case 's': /* set a parameter */
203			if (badcom("set"))
204			goto commerr;
205			setparam(args);
206			break;
207			case 'n': /* new picture */
208			if (badcom("new"))
209			goto commerr;
210			newimage();
211			break;
212			case 't': /* trace a ray */
213			if (badcom("trace"))
214			goto commerr;
215			traceray(args);
216			break;
217			case 'a': /* aim camera */
218			if (badcom("aim"))
219			goto commerr;
220			getaim(args);
221			break;
222			case 'm': /* move camera */
223			if (badcom("move"))
224			goto commerr;
225			getmove(args);
226			break;
227	greg	1.8	case 'r': /* rotate/repaint */
228			if (badcom("rotate")) {
229			if (badcom("repaint"))
230			goto commerr;
231			getrepaint(args);
232			break;
233			}
234	greg	1.1	getrotate(args);
235			break;
236			case 'p': /* pivot view */
237			if (badcom("pivot"))
238			goto commerr;
239			getpivot(args);
240			break;
241			case CTRL(R): /* redraw */
242			redraw();
243			break;
244			case 'w': /* write */
245			if (badcom("write"))
246			goto commerr;
247			writepict(args);
248			break;
249			case 'q': /* quit */
250			if (badcom("quit"))
251			goto commerr;
252			quit(0);
253			case CTRL(C): /* interrupt */
254			goto again;
255			#ifdef SIGTSTP
256			case CTRL(Z): /* stop */
257			devclose();
258			kill(0, SIGTSTP);
259			/* pc stops here */
260			devopen(devname);
261			redraw();
262			break;
263			#endif
264			case '\0': /* continue */
265			break;
266			default:;
267			commerr:
268			if (iscntrl(inpbuf[0]))
269			sprintf(errmsg, "^%c: unknown control",
270			inpbuf[0]\|0100);
271			else
272			sprintf(errmsg, "%s: unknown command", inpbuf);
273			error(COMMAND, errmsg);
274			break;
275			}
276			#undef badcom
277			}
278
279
280			rsample() /* sample the image */
281			{
282			int xsiz, ysiz, y;
283			RECT r;
284			PNODE *p;
285			register RECT *rl;
286			register PNODE **pl;
287			register int x;
288			/*
289			* We initialize the bottom row in the image at our current
290			* resolution. During sampling, we check super-pixels to the
291			* right and above by calling bigdiff(). If there is a significant
292			* difference, we subsample the super-pixels. The testing process
293			* includes initialization of the next row.
294			*/
295	greg	1.9	xsiz = (((pframe.r-pframe.l)<<pdepth)+hresolu-1) / hresolu;
296			ysiz = (((pframe.u-pframe.d)<<pdepth)+vresolu-1) / vresolu;
297	greg	1.1	rl = (RECT )malloc(xsizsizeof(RECT));
298	greg	1.12	if (rl == NULL)
299	greg	1.14	return;
300	greg	1.1	pl = (PNODE *)malloc(xsizsizeof(PNODE *));
301	greg	1.12	if (pl == NULL)
302	greg	1.14	return;
303	greg	1.1	/*
304			* Initialize the bottom row.
305			*/
306			rl[0].l = rl[0].d = 0;
307	greg	1.9	rl[0].r = hresolu; rl[0].u = vresolu;
308	greg	1.1	pl[0] = findrect(pframe.l, pframe.d, &ptrunk, rl, pdepth);
309			for (x = 1; x < xsiz; x++) {
310			rl[x].l = rl[x].d = 0;
311	greg	1.9	rl[x].r = hresolu; rl[x].u = vresolu;
312			pl[x] = findrect(pframe.l+((x*hresolu)>>pdepth),
313	greg	1.1	pframe.d, &ptrunk, rl+x, pdepth);
314			}
315			/* sample the image */
316			for (y = 0; /* y < ysiz */ ; y++) {
317			for (x = 0; x < xsiz-1; x++) {
318			if (dev->inpready)
319			goto escape;
320			/*
321			* Test super-pixel to the right.
322			*/
323			if (pl[x] != pl[x+1] && bigdiff(pl[x]->v,
324			pl[x+1]->v, maxdiff)) {
325			refine(pl[x], rl[x].l, rl[x].d,
326			rl[x].r, rl[x].u, 1);
327			refine(pl[x+1], rl[x+1].l, rl[x+1].d,
328			rl[x+1].r, rl[x+1].u, 1);
329			}
330			}
331			if (y >= ysiz-1)
332			break;
333			for (x = 0; x < xsiz; x++) {
334			if (dev->inpready)
335			goto escape;
336			/*
337			* Find super-pixel at this position in next row.
338			*/
339			r.l = r.d = 0;
340	greg	1.9	r.r = hresolu; r.u = vresolu;
341			p = findrect(pframe.l+((x*hresolu)>>pdepth),
342			pframe.d+(((y+1)*vresolu)>>pdepth),
343	greg	1.1	&ptrunk, &r, pdepth);
344			/*
345			* Test super-pixel in next row.
346			*/
347			if (pl[x] != p && bigdiff(pl[x]->v, p->v, maxdiff)) {
348			refine(pl[x], rl[x].l, rl[x].d,
349			rl[x].r, rl[x].u, 1);
350			refine(p, r.l, r.d, r.r, r.u, 1);
351			}
352			/*
353			* Copy into super-pixel array.
354			*/
355			rl[x].l = r.l; rl[x].d = r.d;
356			rl[x].r = r.r; rl[x].u = r.u;
357			pl[x] = p;
358			}
359			}
360			escape:
361			free((char *)rl);
362			free((char *)pl);
363			}
364
365
366			int
367			refine(p, xmin, ymin, xmax, ymax, pd) /* refine a node */
368			register PNODE *p;
369			int xmin, ymin, xmax, ymax;
370			int pd;
371			{
372			int growth;
373			int mx, my;
374			int i;
375
376			if (dev->inpready) /* quit for input */
377			return(0);
378
379			if (pd <= 0) /* depth limit */
380			return(0);
381
382			mx = (xmin + xmax) >> 1;
383			my = (ymin + ymax) >> 1;
384			growth = 0;
385
386			if (p->kid == NULL) { /* subdivide */
387
388			if ((p->kid = newptree()) == NULL)
389	greg	1.14	return(growth);
390	greg	1.1	/*
391			* The following paint order can leave a black pixel
392			* when redraw() is called in (*dev->paintr)().
393			*/
394			if (p->x >= mx && p->y >= my)
395			pcopy(p, p->kid+UR);
396			else
397			paint(p->kid+UR, mx, my, xmax, ymax);
398			if (p->x < mx && p->y >= my)
399			pcopy(p, p->kid+UL);
400			else
401			paint(p->kid+UL, xmin, my, mx, ymax);
402			if (p->x >= mx && p->y < my)
403			pcopy(p, p->kid+DR);
404			else
405			paint(p->kid+DR, mx, ymin, xmax, my);
406			if (p->x < mx && p->y < my)
407			pcopy(p, p->kid+DL);
408			else
409			paint(p->kid+DL, xmin, ymin, mx, my);
410
411			growth++;
412			}
413			/* do children */
414			if (mx > pframe.l) {
415			if (my > pframe.d)
416			growth += refine(p->kid+DL, xmin, ymin, mx, my, pd-1);
417			if (my < pframe.u)
418			growth += refine(p->kid+UL, xmin, my, mx, ymax, pd-1);
419			}
420			if (mx < pframe.r) {
421			if (my > pframe.d)
422			growth += refine(p->kid+DR, mx, ymin, xmax, my, pd-1);
423			if (my < pframe.u)
424			growth += refine(p->kid+UR, mx, my, xmax, ymax, pd-1);
425			}
426			/* recompute sum */
427			if (growth) {
428			setcolor(p->v, 0.0, 0.0, 0.0);
429			for (i = 0; i < 4; i++)
430			addcolor(p->v, p->kid[i].v);
431			scalecolor(p->v, 0.25);
432			}
433			return(growth);
434			}