src/rt/rview.c

/* Copyright (c) 1992 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  directinvis = 0;                   /* sources invisible? */
double  srcsizerat = 0.;                /* maximum ratio source size/dist. */

double  specthresh = .3;                /* specular sampling threshold */
double  specjitter = 1.;                /* specular sampling jitter */

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     32768           /* 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)
        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"))
#ifdef  MSTATS
                {
                        if (badcom("memory"))
                                goto commerr;
                        printmemstats(stderr);
                        break;
                }
#else
                        goto commerr;
#endif
                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) {
                free((char *)rl);
                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 || errno == ENOMEM)
                                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 || errno == ENOMEM)
                                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(0);
                /*
                 *  The following paint order can leave a black pixel
                 *  if 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:	2.7
Committed:	Wed Sep 9 22:19:42 1992 UTC (31 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.6:	+5 -3 lines
Log Message:	minor oversight in rsample()
#	User	Rev	Content
1	greg	2.7	/* Copyright (c) 1992 Regents of the University of California */
2	greg	1.1
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	1.19	int directinvis = 0; /* sources invisible? */
39	greg	1.21	double srcsizerat = 0.; /* maximum ratio source size/dist. */
40	greg	1.1
41	greg	2.6	double specthresh = .3; /* specular sampling threshold */
42	greg	2.5	double specjitter = 1.; /* specular sampling jitter */
43
44	greg	1.1	int maxdepth = 4; /* maximum recursion depth */
45			double minweight = 1e-2; /* minimum ray weight */
46
47			COLOR ambval = BLKCOLOR; /* ambient value */
48			double ambacc = 0.2; /* ambient accuracy */
49	greg	1.5	int ambres = 8; /* ambient resolution */
50	greg	1.1	int ambdiv = 32; /* ambient divisions */
51			int ambssamp = 0; /* ambient super-samples */
52			int ambounce = 0; /* ambient bounces */
53			char amblist[128]; / ambient include/exclude list */
54			int ambincl = -1; /* include == 1, exclude == 0 */
55
56			int greyscale = 0; /* map colors to brightness? */
57	greg	1.11	char devname = dev_default; / output device name */
58	greg	1.1
59			struct driver dev = NULL; / driver functions */
60
61			VIEW oldview; /* previous view parameters */
62
63			PNODE ptrunk; /* the base of our image */
64			RECT pframe; /* current frame boundaries */
65			int pdepth; /* image depth in current frame */
66
67	greg	1.12	static char reserve_mem = NULL; / pre-allocated reserve memory */
68
69	greg	1.20	#define RESERVE_AMT 32768 /* amount of memory to reserve */
70	greg	1.12
71	greg	2.4	#define CTRL(c) ((c)-'@')
72	greg	1.1
73
74			quit(code) /* quit program */
75			int code;
76			{
77			devclose();
78			exit(code);
79			}
80
81
82			devopen(dname) /* open device driver */
83			char *dname;
84			{
85	greg	1.6	extern char progname, octname;
86	greg	1.7	char *id;
87	greg	1.1	register int i;
88	greg	1.6
89	greg	1.7	id = octname!=NULL ? octname : progname;
90	greg	1.1	/* check device table */
91			for (i = 0; devtable[i].name; i++)
92			if (!strcmp(dname, devtable[i].name))
93	greg	1.7	if ((dev = (*devtable[i].init)(dname, id)) == NULL) {
94	greg	1.1	sprintf(errmsg, "cannot initialize %s", dname);
95			error(USER, errmsg);
96			} else
97			return;
98			/* not there, try exec */
99	greg	1.7	if ((dev = comm_init(dname, id)) == NULL) {
100	greg	1.1	sprintf(errmsg, "cannot start device \"%s\"", dname);
101			error(USER, errmsg);
102			}
103			}
104
105
106			devclose() /* close our device */
107			{
108			if (dev != NULL)
109			(*dev->close)();
110			dev = NULL;
111			}
112
113
114			printdevices() /* print list of output devices */
115			{
116			register int i;
117
118			for (i = 0; devtable[i].name; i++)
119			printf("%-16s # %s\n", devtable[i].name, devtable[i].descrip);
120			}
121
122
123			rview() /* do a view */
124			{
125			char buf[32];
126
127			devopen(devname); /* open device */
128	greg	1.14	newimage(); /* start image (calls fillreserves) */
129
130	greg	1.1	for ( ; ; ) { /* quit in command() */
131	greg	1.14	while (hresolu <= 1<<pdepth && vresolu <= 1<<pdepth)
132	greg	1.1	command("done: ");
133	greg	1.14	while (reserve_mem == NULL)
134			command("out of memory: ");
135			errno = 0;
136			if (hresolu <= psample<<pdepth && vresolu <= psample<<pdepth) {
137	greg	1.1	sprintf(buf, "%d sampling...\n", 1<<pdepth);
138			(*dev->comout)(buf);
139			rsample();
140			} else {
141			sprintf(buf, "%d refining...\n", 1<<pdepth);
142			(*dev->comout)(buf);
143	greg	1.9	refine(&ptrunk, 0, 0, hresolu, vresolu, pdepth+1);
144	greg	1.1	}
145	greg	1.14	if (errno == ENOMEM) /* ran out of memory */
146			freereserves();
147			else if (dev->inpready) /* noticed some input */
148	greg	1.1	command(": ");
149	greg	1.14	else /* finished this depth */
150	greg	1.1	pdepth++;
151			}
152			}
153
154
155	greg	1.14	fillreserves() /* fill memory reserves */
156	greg	1.12	{
157			if (reserve_mem != NULL)
158	greg	1.14	return;
159	greg	1.12	reserve_mem = malloc(RESERVE_AMT);
160			}
161
162
163	greg	1.14	freereserves() /* free memory reserves */
164	greg	1.12	{
165	greg	1.14	if (reserve_mem == NULL)
166			return;
167	greg	1.12	free(reserve_mem);
168			reserve_mem = NULL;
169			}
170
171
172	greg	1.1	command(prompt) /* get/execute command */
173			char *prompt;
174			{
175			#define badcom(s) strncmp(s, inpbuf, args-inpbuf-1)
176			char inpbuf[256];
177			char *args;
178			again:
179	greg	1.10	(dev->comin)(inpbuf, prompt); / get command + arguments */
180	greg	1.1	for (args = inpbuf; args && args != ' '; args++)
181			;
182			if (args) args++ = '\0';
183			else *++args = '\0';
184
185			switch (inpbuf[0]) {
186			case 'f': /* new frame */
187			if (badcom("frame"))
188			goto commerr;
189			getframe(args);
190			break;
191			case 'v': /* view */
192			if (badcom("view"))
193			goto commerr;
194			getview(args);
195			break;
196			case 'l': /* last view */
197			if (badcom("last"))
198			goto commerr;
199			lastview(args);
200			break;
201			case 'e': /* exposure */
202			if (badcom("exposure"))
203			goto commerr;
204			getexposure(args);
205			break;
206			case 's': /* set a parameter */
207			if (badcom("set"))
208			goto commerr;
209			setparam(args);
210			break;
211			case 'n': /* new picture */
212			if (badcom("new"))
213			goto commerr;
214			newimage();
215			break;
216			case 't': /* trace a ray */
217			if (badcom("trace"))
218			goto commerr;
219			traceray(args);
220			break;
221			case 'a': /* aim camera */
222			if (badcom("aim"))
223			goto commerr;
224			getaim(args);
225			break;
226			case 'm': /* move camera */
227			if (badcom("move"))
228	greg	2.2	#ifdef MSTATS
229			{
230			if (badcom("memory"))
231			goto commerr;
232			printmemstats(stderr);
233			break;
234			}
235			#else
236	greg	1.1	goto commerr;
237	greg	2.2	#endif
238	greg	1.1	getmove(args);
239			break;
240	greg	1.8	case 'r': /* rotate/repaint */
241			if (badcom("rotate")) {
242			if (badcom("repaint"))
243			goto commerr;
244			getrepaint(args);
245			break;
246			}
247	greg	1.1	getrotate(args);
248			break;
249			case 'p': /* pivot view */
250			if (badcom("pivot"))
251			goto commerr;
252			getpivot(args);
253			break;
254	greg	2.4	case CTRL('R'): /* redraw */
255	greg	1.1	redraw();
256			break;
257			case 'w': /* write */
258			if (badcom("write"))
259			goto commerr;
260			writepict(args);
261			break;
262			case 'q': /* quit */
263			if (badcom("quit"))
264			goto commerr;
265			quit(0);
266	greg	2.4	case CTRL('C'): /* interrupt */
267	greg	1.1	goto again;
268			#ifdef SIGTSTP
269	greg	2.4	case CTRL('Z'): /* stop */
270	greg	1.1	devclose();
271			kill(0, SIGTSTP);
272			/* pc stops here */
273			devopen(devname);
274			redraw();
275			break;
276			#endif
277			case '\0': /* continue */
278			break;
279			default:;
280			commerr:
281			if (iscntrl(inpbuf[0]))
282			sprintf(errmsg, "^%c: unknown control",
283			inpbuf[0]\|0100);
284			else
285			sprintf(errmsg, "%s: unknown command", inpbuf);
286			error(COMMAND, errmsg);
287			break;
288			}
289			#undef badcom
290			}
291
292
293			rsample() /* sample the image */
294			{
295			int xsiz, ysiz, y;
296			RECT r;
297			PNODE *p;
298			register RECT *rl;
299			register PNODE **pl;
300			register int x;
301			/*
302			* We initialize the bottom row in the image at our current
303			* resolution. During sampling, we check super-pixels to the
304			* right and above by calling bigdiff(). If there is a significant
305			* difference, we subsample the super-pixels. The testing process
306			* includes initialization of the next row.
307			*/
308	greg	1.9	xsiz = (((pframe.r-pframe.l)<<pdepth)+hresolu-1) / hresolu;
309			ysiz = (((pframe.u-pframe.d)<<pdepth)+vresolu-1) / vresolu;
310	greg	1.1	rl = (RECT )malloc(xsizsizeof(RECT));
311	greg	1.12	if (rl == NULL)
312	greg	1.14	return;
313	greg	1.1	pl = (PNODE *)malloc(xsizsizeof(PNODE *));
314	greg	2.7	if (pl == NULL) {
315			free((char *)rl);
316	greg	1.14	return;
317	greg	2.7	}
318	greg	1.1	/*
319			* Initialize the bottom row.
320			*/
321			rl[0].l = rl[0].d = 0;
322	greg	1.9	rl[0].r = hresolu; rl[0].u = vresolu;
323	greg	1.1	pl[0] = findrect(pframe.l, pframe.d, &ptrunk, rl, pdepth);
324			for (x = 1; x < xsiz; x++) {
325			rl[x].l = rl[x].d = 0;
326	greg	1.9	rl[x].r = hresolu; rl[x].u = vresolu;
327			pl[x] = findrect(pframe.l+((x*hresolu)>>pdepth),
328	greg	1.1	pframe.d, &ptrunk, rl+x, pdepth);
329			}
330			/* sample the image */
331			for (y = 0; /* y < ysiz */ ; y++) {
332			for (x = 0; x < xsiz-1; x++) {
333	greg	1.20	if (dev->inpready \|\| errno == ENOMEM)
334	greg	1.1	goto escape;
335			/*
336			* Test super-pixel to the right.
337			*/
338			if (pl[x] != pl[x+1] && bigdiff(pl[x]->v,
339			pl[x+1]->v, maxdiff)) {
340			refine(pl[x], rl[x].l, rl[x].d,
341			rl[x].r, rl[x].u, 1);
342			refine(pl[x+1], rl[x+1].l, rl[x+1].d,
343			rl[x+1].r, rl[x+1].u, 1);
344			}
345			}
346			if (y >= ysiz-1)
347			break;
348			for (x = 0; x < xsiz; x++) {
349	greg	1.20	if (dev->inpready \|\| errno == ENOMEM)
350	greg	1.1	goto escape;
351			/*
352			* Find super-pixel at this position in next row.
353			*/
354			r.l = r.d = 0;
355	greg	1.9	r.r = hresolu; r.u = vresolu;
356			p = findrect(pframe.l+((x*hresolu)>>pdepth),
357			pframe.d+(((y+1)*vresolu)>>pdepth),
358	greg	1.1	&ptrunk, &r, pdepth);
359			/*
360			* Test super-pixel in next row.
361			*/
362			if (pl[x] != p && bigdiff(pl[x]->v, p->v, maxdiff)) {
363			refine(pl[x], rl[x].l, rl[x].d,
364			rl[x].r, rl[x].u, 1);
365			refine(p, r.l, r.d, r.r, r.u, 1);
366			}
367			/*
368			* Copy into super-pixel array.
369			*/
370			rl[x].l = r.l; rl[x].d = r.d;
371			rl[x].r = r.r; rl[x].u = r.u;
372			pl[x] = p;
373			}
374			}
375			escape:
376			free((char *)rl);
377			free((char *)pl);
378			}
379
380
381			int
382			refine(p, xmin, ymin, xmax, ymax, pd) /* refine a node */
383			register PNODE *p;
384			int xmin, ymin, xmax, ymax;
385			int pd;
386			{
387			int growth;
388			int mx, my;
389			int i;
390
391			if (dev->inpready) /* quit for input */
392			return(0);
393
394			if (pd <= 0) /* depth limit */
395			return(0);
396
397			mx = (xmin + xmax) >> 1;
398			my = (ymin + ymax) >> 1;
399			growth = 0;
400
401			if (p->kid == NULL) { /* subdivide */
402
403			if ((p->kid = newptree()) == NULL)
404	greg	1.20	return(0);
405	greg	1.1	/*
406			* The following paint order can leave a black pixel
407	greg	2.7	* if redraw() is called in (*dev->paintr)().
408	greg	1.1	*/
409			if (p->x >= mx && p->y >= my)
410			pcopy(p, p->kid+UR);
411			else
412			paint(p->kid+UR, mx, my, xmax, ymax);
413			if (p->x < mx && p->y >= my)
414			pcopy(p, p->kid+UL);
415			else
416			paint(p->kid+UL, xmin, my, mx, ymax);
417			if (p->x >= mx && p->y < my)
418			pcopy(p, p->kid+DR);
419			else
420			paint(p->kid+DR, mx, ymin, xmax, my);
421			if (p->x < mx && p->y < my)
422			pcopy(p, p->kid+DL);
423			else
424			paint(p->kid+DL, xmin, ymin, mx, my);
425
426			growth++;
427			}
428			/* do children */
429			if (mx > pframe.l) {
430			if (my > pframe.d)
431			growth += refine(p->kid+DL, xmin, ymin, mx, my, pd-1);
432			if (my < pframe.u)
433			growth += refine(p->kid+UL, xmin, my, mx, ymax, pd-1);
434			}
435			if (mx < pframe.r) {
436			if (my > pframe.d)
437			growth += refine(p->kid+DR, mx, ymin, xmax, my, pd-1);
438			if (my < pframe.u)
439			growth += refine(p->kid+UR, mx, my, xmax, ymax, pd-1);
440			}
441			/* recompute sum */
442			if (growth) {
443			setcolor(p->v, 0.0, 0.0, 0.0);
444			for (i = 0; i < 4; i++)
445			addcolor(p->v, p->kid[i].v);
446			scalecolor(p->v, 0.25);
447			}
448			return(growth);
449			}