src/hd/rhd_qtree.c

/* Copyright (c) 1997 Silicon Graphics, Inc. */

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

/*
 * Quadtree driver support routines.
 */

#include "standard.h"
#include "rhd_qtree.h"

RTREE   qtrunk;                 /* our quadtree trunk */
double  qtDepthEps = .02;       /* epsilon to compare depths (z fraction) */
int     qtMinNodesiz = 2;       /* minimum node dimension (pixels) */

static RLEAF    *leafpile;      /* our collection of leaf values */
static int      nleaves;        /* count of leaves in our pile */
static int      bleaf, tleaf;   /* bottom and top (next) leaf index (ring) */

#define TBUNDLESIZ      409     /* number of twigs in a bundle */

static RTREE    **twigbundle;   /* free twig blocks (NULL term.) */
static int      nexttwig;       /* next free twig */

static RTREE    emptytree;      /* empty tree for test below */

#define is_stump(t)     (!bcmp((char *)(t), (char *)&emptytree, sizeof(RTREE)))


static RTREE *
newtwig()                       /* allocate a twig */
{
        register int    bi;

        if (twigbundle == NULL) {       /* initialize */
                twigbundle = (RTREE **)malloc(sizeof(RTREE *));
                if (twigbundle == NULL)
                        goto memerr;
                twigbundle[0] = NULL;
        }
        bi = nexttwig / TBUNDLESIZ;
        if (twigbundle[bi] == NULL) {   /* new block */
                twigbundle = (RTREE **)realloc((char *)twigbundle,
                                        (bi+2)*sizeof(RTREE *));
                if (twigbundle == NULL)
                        goto memerr;
                twigbundle[bi] = (RTREE *)calloc(TBUNDLESIZ, sizeof(RTREE));
                if (twigbundle[bi] == NULL)
                        goto memerr;
                twigbundle[bi+1] = NULL;
        }
                                /* nexttwig++ % TBUNDLESIZ */
        return(twigbundle[bi] + (nexttwig++ - bi*TBUNDLESIZ));
memerr:
        error(SYSTEM, "out of memory in newtwig");
}


qtFreeTree(really)              /* free allocated twigs */
int     really;
{
        register int    i;

        tmClearHisto();
        bzero((char *)&qtrunk, sizeof(RTREE));
        nexttwig = 0;
        if (twigbundle == NULL)
                return;
        if (!really) {          /* just clear allocated blocks */
                for (i = 0; twigbundle[i] != NULL; i++)
                        bzero((char *)twigbundle[i], TBUNDLESIZ*sizeof(RTREE));
                return;
        }
                                /* else "really" means free up memory */
        for (i = 0; twigbundle[i] != NULL; i++)
                free((char *)twigbundle[i]);
        free((char *)twigbundle);
        twigbundle = NULL;
}


static RLEAF *
newleaf()                       /* allocate a leaf from our pile */
{
        RLEAF   *lp;
        
        lp = leafpile + tleaf++;
        if (tleaf >= nleaves)           /* get next leaf in ring */
                tleaf = 0;
        if (tleaf == bleaf)             /* need to shake some free */
                qtCompost(LFREEPCT);
        return(lp);
}


int
qtAllocLeaves(n)                /* allocate space for n leaves */
int     n;
{
        unsigned        nbytes;
        register unsigned       i;

        qtFreeTree(0);          /* make sure tree is empty */
        if (n <= 0)
                return(0);
        if (nleaves >= n)
                return(nleaves);
        else if (nleaves > 0)
                free((char *)leafpile);
                                /* round space up to nearest power of 2 */
        nbytes = n*sizeof(RLEAF) + 8;
        for (i = 1024; nbytes > i; i <<= 1)
                ;
        n = (i - 8) / sizeof(RLEAF);
        leafpile = (RLEAF *)malloc(n*sizeof(RLEAF));
        if (leafpile == NULL)
                return(-1);
        nleaves = n;
        bleaf = tleaf = 0;
        return(nleaves);
}


qtFreeLeaves()                  /* free our allocated leaves and twigs */
{
        qtFreeTree(1);          /* free tree also */
        if (nleaves <= 0)
                return;
        free((char *)leafpile);
        leafpile = NULL;
        nleaves = 0;
}


static
shaketree(tp)                   /* shake dead leaves from tree */
register RTREE  *tp;
{
        register int    i, li;

        for (i = 0; i < 4; i++)
                if (tp->flgs & BRF(i))
                        shaketree(tp->k[i].b);
                else if (tp->k[i].l != NULL) {
                        li = tp->k[i].l - leafpile;
                        if (bleaf < tleaf ? (li < bleaf || li >= tleaf) :
                                        (li < bleaf && li >= tleaf)) {
                                tmAddHisto(&tp->k[i].l->brt, 1, -1);
                                tp->k[i].l = NULL;
                        }
                }
}


int
qtCompost(pct)                  /* free up some leaves */
int     pct;
{
        int     nused, nclear;

        if (is_stump(&qtrunk))
                return(0);
                                /* figure out how many leaves to clear */
        nclear = nleaves * pct / 100;
        nused = tleaf > bleaf ? tleaf-bleaf : tleaf+nleaves-bleaf;
        nclear -= nleaves - nused;      /* less what's already free */
        if (nclear <= 0)
                return(0);
        if (nclear >= nused) {  /* clear them all */
                qtFreeTree(0);
                bleaf = tleaf = 0;
                return(nused);
        }
                                /* else clear leaves from bottom */
        bleaf += nclear;
        if (bleaf >= nleaves) bleaf -= nleaves;
        shaketree(&qtrunk);
        return(nclear);
}


RLEAF *
qtFindLeaf(x, y)                /* find closest leaf to (x,y) */
int     x, y;
{
        register RTREE  *tp = &qtrunk;
        RLEAF   *lp = NULL;
        int     x0=0, y0=0, x1=odev.hres, y1=odev.vres;
        int     mx, my;
        register int    q;
                                        /* check limits */
        if (x < 0 || x >= odev.hres || y < 0 || y >= odev.vres)
                return(NULL);
                                        /* find nearby leaf in our tree */
        for ( ; ; ) {
                for (q = 0; q < 4; q++)         /* find any leaf this level */
                        if (!(tp->flgs & BRF(q)) && tp->k[q].l != NULL) {
                                lp = tp->k[q].l;
                                break;
                        }
                q = 0;                          /* which quadrant are we? */
                mx = (x0 + x1) >> 1;
                my = (y0 + y1) >> 1;
                if (x < mx) x1 = mx;
                else {x0 = mx; q |= 01;}
                if (y < my) y1 = my;
                else {y0 = my; q |= 02;}
                if (tp->flgs & BRF(q)) {        /* branch down if not a leaf */
                        tp = tp->k[q].b;
                        continue;
                }
                if (tp->k[q].l != NULL)         /* good shot! */
                        return(tp->k[q].l);
                return(lp);                     /* else return what we have */
        }
}


static
addleaf(lp)                     /* add a leaf to our tree */
RLEAF   *lp;
{
        register RTREE  *tp = &qtrunk;
        int     x0=0, y0=0, x1=odev.hres, y1=odev.vres;
        RLEAF   *lo = NULL;
        int     x, y, mx, my;
        double  z;
        FVECT   ip, wp;
        register int    q;
                                        /* compute leaf location */
        VCOPY(wp, lp->wp);
        viewloc(ip, &odev.v, wp);
        if (ip[2] <= 0. || ip[0] < 0. || ip[0] >= 1.
                        || ip[1] < 0. || ip[1] >= 1.)
                return;
        x = ip[0] * odev.hres;
        y = ip[1] * odev.vres;
        z = ip[2];
                                        /* find the place for it */
        for ( ; ; ) {
                q = 0;                          /* which quadrant? */
                mx = (x0 + x1) >> 1;
                my = (y0 + y1) >> 1;
                if (x < mx) x1 = mx;
                else {x0 = mx; q |= 01;}
                if (y < my) y1 = my;
                else {y0 = my; q |= 02;}
                if (tp->flgs & BRF(q)) {        /* move to next branch */
                        tp->flgs |= CHF(q);             /* not sure; guess */
                        tp = tp->k[q].b;
                        continue;
                }
                if (tp->k[q].l == NULL) {       /* found stem for leaf */
                        tp->k[q].l = lp;
                        tp->flgs |= CHF(q);
                        break;
                }       
                                                /* check existing leaf */
                if (lo != tp->k[q].l) {
                        lo = tp->k[q].l;
                        VCOPY(wp, lo->wp);
                        viewloc(ip, &odev.v, wp);
                }
                                                /* is node minimum size? */
                if (x1-x0 <= qtMinNodesiz || y1-y0 <= qtMinNodesiz) {
                        if (z > (1.-qtDepthEps)*ip[2])  /* who is closer? */
                                return;                 /* old one is */
                        tp->k[q].l = lp;                /* new one is */
                        tp->flgs |= CHF(q);
                        tmAddHisto(&lo->brt, 1, -1);    /* drop old one */
                        break;
                }
                tp->flgs |= CHBRF(q);           /* else grow tree */
                tp = tp->k[q].b = newtwig();
                tp->flgs |= CH_ANY;             /* all new */
                q = 0;                          /* old leaf -> new branch */
                mx = ip[0] * odev.hres;
                my = ip[1] * odev.vres;
                if (mx >= (x0 + x1) >> 1) q |= 01;
                if (my >= (y0 + y1) >> 1) q |= 02;
                tp->k[q].l = lo;
        }
        tmAddHisto(&lp->brt, 1, 1);     /* add leaf to histogram */
}


dev_value(c, p)                 /* add a pixel value to our output queue */
COLR    c;
FVECT   p;
{
        register RLEAF  *lp;

        lp = newleaf();
        VCOPY(lp->wp, p);
        tmCvColrs(&lp->brt, lp->chr, c, 1);
        addleaf(lp);
}


qtReplant()                     /* replant our tree using new view */
{
        register int    i;

        if (bleaf == tleaf)             /* anything to replant? */
                return;
        qtFreeTree(0);                  /* blow the tree away */
                                        /* now rebuild it */
        for (i = bleaf; i != tleaf; ) {
                addleaf(leafpile+i);
                if (++i >= nleaves) i = 0;
        }
        tmComputeMapping(0., 0., 0.);   /* update the display */
        qtUpdate();
}


static
redraw(ca, tp, x0, y0, x1, y1, l)       /* redraw portion of a tree */
BYTE    ca[3];          /* returned average color */
register RTREE  *tp;
int     x0, y0, x1, y1;
int     l[2][2];
{
        int     csm[3], nc;
        BYTE    rgb[3];
        int     quads = CH_ANY;
        int     mx, my;
        register int    i;
                                        /* compute midpoint */
        mx = (x0 + x1) >> 1;
        my = (y0 + y1) >> 1;
                                        /* see what to do */
        if (l[0][0] >= mx)
                quads &= ~(CHF(2)|CHF(0));
        else if (l[0][1] <= mx)
                quads &= ~(CHF(3)|CHF(1));
        if (l[1][0] >= my)
                quads &= ~(CHF(1)|CHF(0));
        else if (l[1][1] <= my)
                quads &= ~(CHF(3)|CHF(2));
        tp->flgs &= ~quads;             /* mark them done */
        csm[0] = csm[1] = csm[2] = nc = 0;
                                        /* do leaves first */
        for (i = 0; i < 4; i++)
                if (quads & CHF(i) && !(tp->flgs & BRF(i)) &&
                                tp->k[i].l != NULL) {
                        tmMapPixels(rgb, &tp->k[i].l->brt, tp->k[i].l->chr, 1);
                        dev_paintr(rgb, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my);
                        csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
                        nc++;
                        quads &= ~CHF(i);
                }
                                        /* now do branches */
        for (i = 0; i < 4; i++)
                if (quads & CHF(i) && tp->flgs & BRF(i)) {
                        redraw(rgb, tp->k[i].b, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my, l);
                        csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
                        nc++;
                        quads &= ~CHF(i);
                }
        if (nc > 1) {
                ca[0] = csm[0]/nc; ca[1] = csm[1]/nc; ca[2] = csm[2]/nc;
        } else {
                ca[0] = csm[0]; ca[1] = csm[1]; ca[2] = csm[2];
        }
        if (!quads) return;
                                        /* fill in gaps with average */
        for (i = 0; i < 4; i++)
                if (quads & CHF(i))
                        dev_paintr(ca, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my);
}


static
update(ca, tp, x0, y0, x1, y1)  /* update tree display as needed */
BYTE    ca[3];          /* returned average color */
register RTREE  *tp;
int     x0, y0, x1, y1;
{
        int     csm[3], nc;
        BYTE    rgb[3];
        int     gaps = 0;
        int     mx, my;
        register int    i;
                                        /* compute midpoint */
        mx = (x0 + x1) >> 1;
        my = (y0 + y1) >> 1;
        csm[0] = csm[1] = csm[2] = nc = 0;
                                        /* do leaves first */
        for (i = 0; i < 4; i++)
                if ((tp->flgs & CHBRF(i)) == CHF(i)) {
                        if (tp->k[i].l == NULL) {
                                gaps |= 1<<i;   /* empty stem */
                                continue;
                        }
                        tmMapPixels(rgb, &tp->k[i].l->brt, tp->k[i].l->chr, 1);
                        dev_paintr(rgb, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my);
                        csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
                        nc++;
                }
                                        /* now do branches */
        for (i = 0; i < 4; i++)
                if ((tp->flgs & CHBRF(i)) == CHBRF(i)) {
                        update(rgb, tp->k[i].b, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my);
                        csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
                        nc++;
                }
        if (nc > 1) {
                ca[0] = csm[0]/nc; ca[1] = csm[1]/nc; ca[2] = csm[2]/nc;
        } else {
                ca[0] = csm[0]; ca[1] = csm[1]; ca[2] = csm[2];
        }
                                        /* fill in gaps with average */
        for (i = 0; gaps && i < 4; gaps >>= 1, i++)
                if (gaps & 01)
                        dev_paintr(ca, i&01 ? mx : x0, i&02 ? my : y0,
                                        i&01 ? x1 : mx, i&02 ? y1 : my);
        tp->flgs &= ~CH_ANY;            /* all done */
}


qtRedraw(x0, y0, x1, y1)        /* redraw part of our screen */
int     x0, y0, x1, y1;
{
        int     lim[2][2];
        BYTE    ca[3];

        if (is_stump(&qtrunk))
                return;
        if ((lim[0][0]=x0) <= 0 & (lim[1][0]=y0) <= 0 &
                (lim[0][1]=x1) >= odev.hres-1 & (lim[1][1]=y1) >= odev.vres-1
                        || tmTop->lumap == NULL)
                if (tmComputeMapping(0., 0., 0.) != TM_E_OK)
                        return;
        redraw(ca, &qtrunk, 0, 0, odev.hres, odev.vres, lim);
}


qtUpdate()                      /* update our tree display */
{
        BYTE    ca[3];

        if (is_stump(&qtrunk))
                return;
        if (tmTop->lumap == NULL)
                tmComputeMapping(0., 0., 0.);
        update(ca, &qtrunk, 0, 0, odev.hres, odev.vres);
}
Revision:	3.4
Committed:	Fri Nov 21 09:52:06 1997 UTC (26 years, 5 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 3.3:	+18 -10 lines
Log Message:	fixed bug in newleaf()
#	User	Rev	Content
1	gregl	3.1	/* Copyright (c) 1997 Silicon Graphics, Inc. */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ SGI";
5			#endif
6
7			/*
8			* Quadtree driver support routines.
9			*/
10
11			#include "standard.h"
12			#include "rhd_qtree.h"
13
14	gregl	3.2	RTREE qtrunk; /* our quadtree trunk */
15			double qtDepthEps = .02; /* epsilon to compare depths (z fraction) */
16			int qtMinNodesiz = 2; /* minimum node dimension (pixels) */
17
18	gregl	3.1	static RLEAF leafpile; / our collection of leaf values */
19			static int nleaves; /* count of leaves in our pile */
20			static int bleaf, tleaf; /* bottom and top (next) leaf index (ring) */
21
22			#define TBUNDLESIZ 409 /* number of twigs in a bundle */
23
24			static RTREE *twigbundle; / free twig blocks (NULL term.) */
25			static int nexttwig; /* next free twig */
26
27			static RTREE emptytree; /* empty tree for test below */
28
29			#define is_stump(t) (!bcmp((char )(t), (char )&emptytree, sizeof(RTREE)))
30
31
32			static RTREE *
33			newtwig() /* allocate a twig */
34			{
35			register int bi;
36
37			if (twigbundle == NULL) { /* initialize */
38			twigbundle = (RTREE *)malloc(sizeof(RTREE ));
39			if (twigbundle == NULL)
40			goto memerr;
41			twigbundle[0] = NULL;
42			}
43			bi = nexttwig / TBUNDLESIZ;
44			if (twigbundle[bi] == NULL) { /* new block */
45			twigbundle = (RTREE *)realloc((char )twigbundle,
46			(bi+2)sizeof(RTREE ));
47			if (twigbundle == NULL)
48			goto memerr;
49			twigbundle[bi] = (RTREE *)calloc(TBUNDLESIZ, sizeof(RTREE));
50			if (twigbundle[bi] == NULL)
51			goto memerr;
52			twigbundle[bi+1] = NULL;
53			}
54			/* nexttwig++ % TBUNDLESIZ */
55			return(twigbundle[bi] + (nexttwig++ - bi*TBUNDLESIZ));
56			memerr:
57			error(SYSTEM, "out of memory in newtwig");
58			}
59
60
61	gregl	3.3	qtFreeTree(really) /* free allocated twigs */
62	gregl	3.1	int really;
63			{
64			register int i;
65
66	gregl	3.4	tmClearHisto();
67	gregl	3.1	bzero((char *)&qtrunk, sizeof(RTREE));
68			nexttwig = 0;
69			if (twigbundle == NULL)
70			return;
71			if (!really) { /* just clear allocated blocks */
72			for (i = 0; twigbundle[i] != NULL; i++)
73			bzero((char )twigbundle[i], TBUNDLESIZsizeof(RTREE));
74			return;
75			}
76			/* else "really" means free up memory */
77			for (i = 0; twigbundle[i] != NULL; i++)
78			free((char *)twigbundle[i]);
79			free((char *)twigbundle);
80			twigbundle = NULL;
81			}
82
83
84			static RLEAF *
85			newleaf() /* allocate a leaf from our pile */
86			{
87	gregl	3.4	RLEAF *lp;
88
89			lp = leafpile + tleaf++;
90			if (tleaf >= nleaves) /* get next leaf in ring */
91	gregl	3.1	tleaf = 0;
92			if (tleaf == bleaf) /* need to shake some free */
93			qtCompost(LFREEPCT);
94	gregl	3.4	return(lp);
95	gregl	3.1	}
96
97
98			int
99			qtAllocLeaves(n) /* allocate space for n leaves */
100			int n;
101			{
102			unsigned nbytes;
103			register unsigned i;
104
105	gregl	3.3	qtFreeTree(0); /* make sure tree is empty */
106	gregl	3.1	if (n <= 0)
107			return(0);
108			if (nleaves >= n)
109			return(nleaves);
110			else if (nleaves > 0)
111			free((char *)leafpile);
112			/* round space up to nearest power of 2 */
113			nbytes = n*sizeof(RLEAF) + 8;
114			for (i = 1024; nbytes > i; i <<= 1)
115			;
116			n = (i - 8) / sizeof(RLEAF);
117			leafpile = (RLEAF )malloc(nsizeof(RLEAF));
118			if (leafpile == NULL)
119			return(-1);
120			nleaves = n;
121			bleaf = tleaf = 0;
122			return(nleaves);
123			}
124
125
126			qtFreeLeaves() /* free our allocated leaves and twigs */
127			{
128	gregl	3.3	qtFreeTree(1); /* free tree also */
129	gregl	3.1	if (nleaves <= 0)
130			return;
131			free((char *)leafpile);
132			leafpile = NULL;
133			nleaves = 0;
134			}
135
136
137			static
138			shaketree(tp) /* shake dead leaves from tree */
139			register RTREE *tp;
140			{
141			register int i, li;
142
143			for (i = 0; i < 4; i++)
144	gregl	3.2	if (tp->flgs & BRF(i))
145			shaketree(tp->k[i].b);
146			else if (tp->k[i].l != NULL) {
147	gregl	3.1	li = tp->k[i].l - leafpile;
148			if (bleaf < tleaf ? (li < bleaf \|\| li >= tleaf) :
149			(li < bleaf && li >= tleaf)) {
150			tmAddHisto(&tp->k[i].l->brt, 1, -1);
151			tp->k[i].l = NULL;
152			}
153			}
154			}
155
156
157			int
158			qtCompost(pct) /* free up some leaves */
159			int pct;
160			{
161			int nused, nclear;
162	gregl	3.4
163			if (is_stump(&qtrunk))
164			return(0);
165	gregl	3.1	/* figure out how many leaves to clear */
166			nclear = nleaves * pct / 100;
167	gregl	3.4	nused = tleaf > bleaf ? tleaf-bleaf : tleaf+nleaves-bleaf;
168			nclear -= nleaves - nused; /* less what's already free */
169	gregl	3.1	if (nclear <= 0)
170			return(0);
171			if (nclear >= nused) { /* clear them all */
172	gregl	3.3	qtFreeTree(0);
173	gregl	3.1	bleaf = tleaf = 0;
174			return(nused);
175			}
176			/* else clear leaves from bottom */
177	gregl	3.4	bleaf += nclear;
178			if (bleaf >= nleaves) bleaf -= nleaves;
179	gregl	3.1	shaketree(&qtrunk);
180			return(nclear);
181			}
182
183
184	gregl	3.3	RLEAF *
185			qtFindLeaf(x, y) /* find closest leaf to (x,y) */
186			int x, y;
187			{
188			register RTREE *tp = &qtrunk;
189			RLEAF *lp = NULL;
190			int x0=0, y0=0, x1=odev.hres, y1=odev.vres;
191			int mx, my;
192			register int q;
193			/* check limits */
194			if (x < 0 \|\| x >= odev.hres \|\| y < 0 \|\| y >= odev.vres)
195			return(NULL);
196			/* find nearby leaf in our tree */
197			for ( ; ; ) {
198			for (q = 0; q < 4; q++) /* find any leaf this level */
199			if (!(tp->flgs & BRF(q)) && tp->k[q].l != NULL) {
200			lp = tp->k[q].l;
201			break;
202			}
203			q = 0; /* which quadrant are we? */
204			mx = (x0 + x1) >> 1;
205			my = (y0 + y1) >> 1;
206			if (x < mx) x1 = mx;
207			else {x0 = mx; q \|= 01;}
208			if (y < my) y1 = my;
209			else {y0 = my; q \|= 02;}
210			if (tp->flgs & BRF(q)) { /* branch down if not a leaf */
211			tp = tp->k[q].b;
212			continue;
213			}
214			if (tp->k[q].l != NULL) /* good shot! */
215			return(tp->k[q].l);
216			return(lp); /* else return what we have */
217			}
218			}
219
220
221	gregl	3.1	static
222			addleaf(lp) /* add a leaf to our tree */
223			RLEAF *lp;
224			{
225			register RTREE *tp = &qtrunk;
226			int x0=0, y0=0, x1=odev.hres, y1=odev.vres;
227			RLEAF *lo = NULL;
228			int x, y, mx, my;
229			double z;
230			FVECT ip, wp;
231			register int q;
232			/* compute leaf location */
233			VCOPY(wp, lp->wp);
234			viewloc(ip, &odev.v, wp);
235			if (ip[2] <= 0. \|\| ip[0] < 0. \|\| ip[0] >= 1.
236			\|\| ip[1] < 0. \|\| ip[1] >= 1.)
237			return;
238			x = ip[0] * odev.hres;
239			y = ip[1] * odev.vres;
240			z = ip[2];
241			/* find the place for it */
242			for ( ; ; ) {
243			q = 0; /* which quadrant? */
244			mx = (x0 + x1) >> 1;
245			my = (y0 + y1) >> 1;
246			if (x < mx) x1 = mx;
247			else {x0 = mx; q \|= 01;}
248			if (y < my) y1 = my;
249			else {y0 = my; q \|= 02;}
250			if (tp->flgs & BRF(q)) { /* move to next branch */
251			tp->flgs \|= CHF(q); /* not sure; guess */
252			tp = tp->k[q].b;
253			continue;
254			}
255			if (tp->k[q].l == NULL) { /* found stem for leaf */
256			tp->k[q].l = lp;
257			tp->flgs \|= CHF(q);
258			break;
259			}
260			/* check existing leaf */
261			if (lo != tp->k[q].l) {
262			lo = tp->k[q].l;
263			VCOPY(wp, lo->wp);
264			viewloc(ip, &odev.v, wp);
265			}
266			/* is node minimum size? */
267			if (x1-x0 <= qtMinNodesiz \|\| y1-y0 <= qtMinNodesiz) {
268			if (z > (1.-qtDepthEps)ip[2]) / who is closer? */
269			return; /* old one is */
270			tp->k[q].l = lp; /* new one is */
271			tp->flgs \|= CHF(q);
272			tmAddHisto(&lo->brt, 1, -1); /* drop old one */
273			break;
274			}
275			tp->flgs \|= CHBRF(q); /* else grow tree */
276			tp = tp->k[q].b = newtwig();
277			tp->flgs \|= CH_ANY; /* all new */
278			q = 0; /* old leaf -> new branch */
279			mx = ip[0] * odev.hres;
280			my = ip[1] * odev.vres;
281			if (mx >= (x0 + x1) >> 1) q \|= 01;
282			if (my >= (y0 + y1) >> 1) q \|= 02;
283			tp->k[q].l = lo;
284			}
285			tmAddHisto(&lp->brt, 1, 1); /* add leaf to histogram */
286			}
287
288
289			dev_value(c, p) /* add a pixel value to our output queue */
290			COLR c;
291			FVECT p;
292			{
293			register RLEAF *lp;
294
295			lp = newleaf();
296			VCOPY(lp->wp, p);
297			tmCvColrs(&lp->brt, lp->chr, c, 1);
298			addleaf(lp);
299			}
300
301
302			qtReplant() /* replant our tree using new view */
303			{
304			register int i;
305
306			if (bleaf == tleaf) /* anything to replant? */
307			return;
308	gregl	3.3	qtFreeTree(0); /* blow the tree away */
309	gregl	3.1	/* now rebuild it */
310			for (i = bleaf; i != tleaf; ) {
311			addleaf(leafpile+i);
312			if (++i >= nleaves) i = 0;
313			}
314			tmComputeMapping(0., 0., 0.); /* update the display */
315			qtUpdate();
316			}
317
318
319			static
320			redraw(ca, tp, x0, y0, x1, y1, l) /* redraw portion of a tree */
321			BYTE ca[3]; /* returned average color */
322			register RTREE *tp;
323			int x0, y0, x1, y1;
324			int l[2][2];
325			{
326			int csm[3], nc;
327			BYTE rgb[3];
328			int quads = CH_ANY;
329			int mx, my;
330			register int i;
331			/* compute midpoint */
332			mx = (x0 + x1) >> 1;
333			my = (y0 + y1) >> 1;
334			/* see what to do */
335			if (l[0][0] >= mx)
336			quads &= ~(CHF(2)\|CHF(0));
337			else if (l[0][1] <= mx)
338			quads &= ~(CHF(3)\|CHF(1));
339			if (l[1][0] >= my)
340			quads &= ~(CHF(1)\|CHF(0));
341			else if (l[1][1] <= my)
342			quads &= ~(CHF(3)\|CHF(2));
343			tp->flgs &= ~quads; /* mark them done */
344			csm[0] = csm[1] = csm[2] = nc = 0;
345			/* do leaves first */
346			for (i = 0; i < 4; i++)
347			if (quads & CHF(i) && !(tp->flgs & BRF(i)) &&
348			tp->k[i].l != NULL) {
349			tmMapPixels(rgb, &tp->k[i].l->brt, tp->k[i].l->chr, 1);
350			dev_paintr(rgb, i&01 ? mx : x0, i&02 ? my : y0,
351			i&01 ? x1 : mx, i&02 ? y1 : my);
352			csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
353			nc++;
354			quads &= ~CHF(i);
355			}
356			/* now do branches */
357			for (i = 0; i < 4; i++)
358			if (quads & CHF(i) && tp->flgs & BRF(i)) {
359			redraw(rgb, tp->k[i].b, i&01 ? mx : x0, i&02 ? my : y0,
360			i&01 ? x1 : mx, i&02 ? y1 : my, l);
361			csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
362			nc++;
363			quads &= ~CHF(i);
364			}
365			if (nc > 1) {
366			ca[0] = csm[0]/nc; ca[1] = csm[1]/nc; ca[2] = csm[2]/nc;
367			} else {
368			ca[0] = csm[0]; ca[1] = csm[1]; ca[2] = csm[2];
369			}
370			if (!quads) return;
371			/* fill in gaps with average */
372			for (i = 0; i < 4; i++)
373			if (quads & CHF(i))
374			dev_paintr(ca, i&01 ? mx : x0, i&02 ? my : y0,
375			i&01 ? x1 : mx, i&02 ? y1 : my);
376			}
377
378
379			static
380			update(ca, tp, x0, y0, x1, y1) /* update tree display as needed */
381			BYTE ca[3]; /* returned average color */
382			register RTREE *tp;
383			int x0, y0, x1, y1;
384			{
385			int csm[3], nc;
386			BYTE rgb[3];
387			int gaps = 0;
388			int mx, my;
389			register int i;
390			/* compute midpoint */
391			mx = (x0 + x1) >> 1;
392			my = (y0 + y1) >> 1;
393			csm[0] = csm[1] = csm[2] = nc = 0;
394			/* do leaves first */
395			for (i = 0; i < 4; i++)
396			if ((tp->flgs & CHBRF(i)) == CHF(i)) {
397			if (tp->k[i].l == NULL) {
398			gaps \|= 1<<i; /* empty stem */
399			continue;
400			}
401			tmMapPixels(rgb, &tp->k[i].l->brt, tp->k[i].l->chr, 1);
402			dev_paintr(rgb, i&01 ? mx : x0, i&02 ? my : y0,
403			i&01 ? x1 : mx, i&02 ? y1 : my);
404			csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
405			nc++;
406			}
407			/* now do branches */
408			for (i = 0; i < 4; i++)
409			if ((tp->flgs & CHBRF(i)) == CHBRF(i)) {
410			update(rgb, tp->k[i].b, i&01 ? mx : x0, i&02 ? my : y0,
411			i&01 ? x1 : mx, i&02 ? y1 : my);
412			csm[0] += rgb[0]; csm[1] += rgb[1]; csm[2] += rgb[2];
413			nc++;
414			}
415			if (nc > 1) {
416			ca[0] = csm[0]/nc; ca[1] = csm[1]/nc; ca[2] = csm[2]/nc;
417			} else {
418			ca[0] = csm[0]; ca[1] = csm[1]; ca[2] = csm[2];
419			}
420			/* fill in gaps with average */
421			for (i = 0; gaps && i < 4; gaps >>= 1, i++)
422			if (gaps & 01)
423			dev_paintr(ca, i&01 ? mx : x0, i&02 ? my : y0,
424			i&01 ? x1 : mx, i&02 ? y1 : my);
425			tp->flgs &= ~CH_ANY; /* all done */
426			}
427
428
429			qtRedraw(x0, y0, x1, y1) /* redraw part of our screen */
430			int x0, y0, x1, y1;
431			{
432			int lim[2][2];
433			BYTE ca[3];
434
435			if (is_stump(&qtrunk))
436			return;
437	gregl	3.4	if ((lim[0][0]=x0) <= 0 & (lim[1][0]=y0) <= 0 &
438			(lim[0][1]=x1) >= odev.hres-1 & (lim[1][1]=y1) >= odev.vres-1
439			\|\| tmTop->lumap == NULL)
440			if (tmComputeMapping(0., 0., 0.) != TM_E_OK)
441			return;
442	gregl	3.1	redraw(ca, &qtrunk, 0, 0, odev.hres, odev.vres, lim);
443			}
444
445
446			qtUpdate() /* update our tree display */
447			{
448			BYTE ca[3];
449
450			if (is_stump(&qtrunk))
451			return;
452			if (tmTop->lumap == NULL)
453			tmComputeMapping(0., 0., 0.);
454			update(ca, &qtrunk, 0, 0, odev.hres, odev.vres);
455			}