src/rt/rv3.c

/* Copyright (c) 1994 Regents of the University of California */

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

/*
 *  rv3.c - miscellaneous routines for rview.
 *
 *     5/11/87
 */

#include  "ray.h"

#include  "octree.h"

#include  "rpaint.h"

#include  "random.h"

#ifndef WFLUSH
#ifdef SPEED
#define WFLUSH          (5*SPEED)
#else
#define WFLUSH          100             /* flush after this many rays */
#endif
#endif

#ifdef  SMLFLT
#define  sscanvec(s,v)  (sscanf(s,"%f %f %f",v,v+1,v+2)==3)
#else
#define  sscanvec(s,v)  (sscanf(s,"%lf %lf %lf",v,v+1,v+2)==3)
#endif


getrect(s, r)                           /* get a box */
char  *s;
register RECT  *r;
{
        int  x0, y0, x1, y1;

        if (*s && !strncmp(s, "all", strlen(s))) {
                r->l = r->d = 0;
                r->r = hresolu;
                r->u = vresolu;
                return(0);
        }
        if (sscanf(s, "%d %d %d %d", &x0, &y0, &x1, &y1) != 4) {
                if (dev->getcur == NULL)
                        return(-1);
                (*dev->comout)("Pick first corner\n");
                if ((*dev->getcur)(&x0, &y0) == ABORT)
                        return(-1);
                (*dev->comout)("Pick second corner\n");
                if ((*dev->getcur)(&x1, &y1) == ABORT)
                        return(-1);
        }
        if (x0 < x1) {
                r->l = x0;
                r->r = x1;
        } else {
                r->l = x1;
                r->r = x0;
        }
        if (y0 < y1) {
                r->d = y0;
                r->u = y1;
        } else {
                r->d = y1;
                r->u = y0;
        }
        if (r->l < 0) r->l = 0;
        if (r->d < 0) r->d = 0;
        if (r->r > hresolu) r->r = hresolu;
        if (r->u > vresolu) r->u = vresolu;
        if (r->l > r->r) r->l = r->r;
        if (r->d > r->u) r->d = r->u;
        return(0);
}


getinterest(s, direc, vec, mp)          /* get area of interest */
char  *s;
int  direc;
FVECT  vec;
double  *mp;
{
        int  x, y;
        RAY  thisray;
        register int  i;

        if (sscanf(s, "%lf", mp) != 1)
                *mp = 1.0;
        else if (*mp < -FTINY)          /* negative zoom is reduction */
                *mp = -1.0 / *mp;
        else if (*mp <= FTINY) {        /* too small */
                error(COMMAND, "illegal magnification");
                return(-1);
        }
        if (!sscanvec(sskip(s), vec)) {
                if (dev->getcur == NULL)
                        return(-1);
                (*dev->comout)("Pick view center\n");
                if ((*dev->getcur)(&x, &y) == ABORT)
                        return(-1);
                if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
                        &ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
                        error(COMMAND, "not on image");
                        return(-1);
                }
                if (!direc || ourview.type == VT_PAR) {
                        rayorigin(&thisray, NULL, PRIMARY, 1.0);
                        if (!localhit(&thisray, &thescene)) {
                                error(COMMAND, "not a local object");
                                return(-1);
                        }
                }
                if (direc)
                        if (ourview.type == VT_PAR)
                                for (i = 0; i < 3; i++)
                                        vec[i] = thisray.rop[i] - ourview.vp[i];
                        else
                                VCOPY(vec, thisray.rdir);
                else
                        VCOPY(vec, thisray.rop);
        } else if (direc)
                        for (i = 0; i < 3; i++)
                                vec[i] -= ourview.vp[i];
        return(0);
}


float *         /* keep consistent with COLOR typedef */
greyof(col)                             /* convert color to greyscale */
register COLOR  col;
{
        static COLOR  gcol;
        double  b;

        b = bright(col);
        setcolor(gcol, b, b, b);
        return(gcol);
}


paint(p, xmin, ymin, xmax, ymax)        /* compute and paint a rectangle */
register PNODE  *p;
int  xmin, ymin, xmax, ymax;
{
        extern unsigned long  nrays;
        static unsigned long  lastflush = 0;
        static RAY  thisray;
        double  h, v;

        if (xmax - xmin <= 0 || ymax - ymin <= 0) {     /* empty */
                p->x = xmin;
                p->y = ymin;
                setcolor(p->v, 0.0, 0.0, 0.0);
                return;
        }
                                                /* jitter ray direction */
        h = xmin + (xmax-xmin)*frandom();
        v = ymin + (ymax-ymin)*frandom();
        
        if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir, &ourview,
                        h/hresolu, v/vresolu)) < -FTINY) {
                setcolor(thisray.rcol, 0.0, 0.0, 0.0);
        } else {
                rayorigin(&thisray, NULL, PRIMARY, 1.0);
                samplendx++;
                rayvalue(&thisray);
        }

        p->x = h;
        p->y = v;
        copycolor(p->v, thisray.rcol);
        scalecolor(p->v, exposure);

        (*dev->paintr)(greyscale?greyof(p->v):p->v, xmin, ymin, xmax, ymax);

        if (dev->flush != NULL && nrays - lastflush >= WFLUSH) {
                lastflush = nrays;
                (*dev->flush)();
        }
}


newimage()                              /* start a new image */
{
                                                /* free old image */
        freepkids(&ptrunk);
                                                /* save reserve memory */
        fillreserves();
                                                /* compute resolution */
        hresolu = dev->xsiz;
        vresolu = dev->ysiz;
        normaspect(viewaspect(&ourview), &dev->pixaspect, &hresolu, &vresolu);
        pframe.l = pframe.d = 0;
        pframe.r = hresolu; pframe.u = vresolu;
        pdepth = 0;
                                                /* clear device */
        (*dev->clear)(hresolu, vresolu);
                                                /* get first value */
        paint(&ptrunk, 0, 0, hresolu, vresolu);
}


redraw()                                /* redraw the image */
{
        (*dev->clear)(hresolu, vresolu);
        (*dev->comout)("redrawing...\n");
        repaint(0, 0, hresolu, vresolu);
        (*dev->comout)("\n");
}


repaint(xmin, ymin, xmax, ymax)                 /* repaint a region */
int  xmin, ymin, xmax, ymax;
{
        RECT  reg;

        reg.l = xmin; reg.r = xmax;
        reg.d = ymin; reg.u = ymax;

        paintrect(&ptrunk, 0, 0, hresolu, vresolu, &reg);
}


paintrect(p, xmin, ymin, xmax, ymax, r)         /* paint picture rectangle */
register PNODE  *p;
int  xmin, ymin, xmax, ymax;
register RECT  *r;
{
        int  mx, my;

        if (xmax - xmin <= 0 || ymax - ymin <= 0)
                return;

        if (p->kid == NULL) {
                (*dev->paintr)(greyscale?greyof(p->v):p->v,
                                xmin, ymin, xmax, ymax);        /* do this */
                return;
        }
        mx = (xmin + xmax) >> 1;                                /* do kids */
        my = (ymin + ymax) >> 1;
        if (mx > r->l) {
                if (my > r->d)
                        paintrect(p->kid+DL, xmin, ymin, mx, my, r);
                if (my < r->u)
                        paintrect(p->kid+UL, xmin, my, mx, ymax, r);
        }
        if (mx < r->r) {
                if (my > r->d)
                        paintrect(p->kid+DR, mx, ymin, xmax, my, r);
                if (my < r->u)
                        paintrect(p->kid+UR, mx, my, xmax, ymax, r);
        }
}


PNODE *
findrect(x, y, p, r, pd)                /* find a rectangle */
int  x, y;
register PNODE  *p;
register RECT  *r;
int  pd;
{
        int  mx, my;

        while (p->kid != NULL && pd--) {

                mx = (r->l + r->r) >> 1;
                my = (r->d + r->u) >> 1;

                if (x < mx) {
                        r->r = mx;
                        if (y < my) {
                                r->u = my;
                                p = p->kid+DL;
                        } else {
                                r->d = my;
                                p = p->kid+UL;
                        }
                } else {
                        r->l = mx;
                        if (y < my) {
                                r->u = my;
                                p = p->kid+DR;
                        } else {
                                r->d = my;
                                p = p->kid+UR;
                        }
                }
        }
        return(p);
}


scalepict(p, sf)                        /* scale picture values */
register PNODE  *p;
double  sf;
{
        scalecolor(p->v, sf);           /* do this node */

        if (p->kid == NULL)
                return;
                                        /* do children */
        scalepict(p->kid+DL, sf);
        scalepict(p->kid+DR, sf);
        scalepict(p->kid+UL, sf);
        scalepict(p->kid+UR, sf);
}


getpictcolrs(yoff, scan, p, xsiz, ysiz) /* get scanline from picture */
int  yoff;
register COLR  *scan;
register PNODE  *p;
int  xsiz, ysiz;
{
        register int  mx;
        int  my;

        if (p->kid == NULL) {                   /* do this node */
                setcolr(scan[0], colval(p->v,RED),
                                colval(p->v,GRN),
                                colval(p->v,BLU));
                for (mx = 1; mx < xsiz; mx++)
                        copycolr(scan[mx], scan[0]);
                return;
        }
                                                /* do kids */
        mx = xsiz >> 1;
        my = ysiz >> 1;
        if (yoff < my) {
                getpictcolrs(yoff, scan, p->kid+DL, mx, my);
                getpictcolrs(yoff, scan+mx, p->kid+DR, xsiz-mx, my);
        } else {
                getpictcolrs(yoff-my, scan, p->kid+UL, mx, ysiz-my);
                getpictcolrs(yoff-my, scan+mx, p->kid+UR, xsiz-mx, ysiz-my);
        }
}


pcopy(p1, p2)                           /* copy paint node p1 into p2 */
register PNODE  *p1, *p2;
{
        copycolor(p2->v, p1->v);
        p2->x = p1->x;
        p2->y = p1->y;
}


freepkids(p)                            /* free pnode's children */
register PNODE  *p;
{
        if (p->kid == NULL)
                return;
        freepkids(p->kid+DL);
        freepkids(p->kid+DR);
        freepkids(p->kid+UL);
        freepkids(p->kid+UR);
        free((char *)p->kid);
        p->kid = NULL;
}


newview(vp)                             /* change viewing parameters */
register VIEW  *vp;
{
        char  *err;

        if ((err = setview(vp)) != NULL) {
                sprintf(errmsg, "view not set - %s", err);
                error(COMMAND, errmsg);
        } else if (bcmp((char *)vp, (char *)&ourview, sizeof(VIEW))) {
                copystruct(&oldview, &ourview);
                copystruct(&ourview, vp);
                newimage();
        }
}


moveview(angle, elev, mag, vc)                  /* move viewpoint */
double  angle, elev, mag;
FVECT  vc;
{
        double  d;
        FVECT  v1;
        VIEW  nv;
        register int  i;

        VCOPY(nv.vup, ourview.vup);
        nv.hoff = ourview.hoff; nv.voff = ourview.voff;
        spinvector(nv.vdir, ourview.vdir, ourview.vup, angle*(PI/180.));
        if (elev != 0.0) {
                fcross(v1, ourview.vup, nv.vdir);
                normalize(v1);
                spinvector(nv.vdir, nv.vdir, v1, elev*(PI/180.));
        }
        if ((nv.type = ourview.type) == VT_PAR) {
                nv.horiz = ourview.horiz / mag;
                nv.vert = ourview.vert / mag;
                d = 0.0;                        /* don't move closer */
                for (i = 0; i < 3; i++)
                        d += (vc[i] - ourview.vp[i])*ourview.vdir[i];
                nv.vfore = ourview.vfore;
                nv.vaft = ourview.vaft;
        } else {
                nv.horiz = ourview.horiz;
                nv.vert = ourview.vert;
                d = sqrt(dist2(ourview.vp, vc)) / mag;
                nv.vfore = ourview.vfore + d - d*mag;
                if (nv.vfore < 0.0) nv.vfore = 0.0;
                nv.vaft = ourview.vaft + d - d*mag;
                if (nv.vaft < nv.vfore) nv.vaft = 0.0;
        }
        for (i = 0; i < 3; i++)
                nv.vp[i] = vc[i] - d*nv.vdir[i];
        newview(&nv);
}


zoomview(vp, zf)                        /* zoom in our out */
register VIEW  *vp;
double  zf;
{
        switch (vp->type) {
        case VT_PAR:                            /* parallel view */
        case VT_ANG:                            /* angular fisheye */
                vp->horiz /= zf;
                vp->vert /= zf;
                return;
        case VT_PER:                            /* perspective view */
                vp->horiz = atan(tan(vp->horiz*(PI/180./2.))/zf) /
                                (PI/180./2.);
                vp->vert = atan(tan(vp->vert*(PI/180./2.))/zf) /
                                (PI/180./2.);
                return;
        case VT_HEM:                            /* hemispherical fisheye */
                vp->horiz = sin(vp->horiz*(PI/180./2.))/zf;
                if (vp->horiz >= 1.0-FTINY)
                        vp->horiz = 180.;
                else
                        vp->horiz = asin(vp->horiz) / (PI/180./2.);
                vp->vert = sin(vp->vert*(PI/180./2.))/zf;
                if (vp->vert >= 1.0-FTINY)
                        vp->vert = 180.;
                else
                        vp->vert = asin(vp->vert) / (PI/180./2.);
                return;
        }
}
Revision:	2.7
Committed:	Thu Dec 22 11:46:19 1994 UTC (29 years, 4 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.6:	+6 -0 lines
Log Message:	made view changes properly manage fore and aft clipping planes
#	User	Rev	Content
1	greg	2.6	/* Copyright (c) 1994 Regents of the University of California */
2	greg	1.1
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* rv3.c - miscellaneous routines for rview.
9			*
10			* 5/11/87
11			*/
12
13			#include "ray.h"
14
15	greg	1.7	#include "octree.h"
16
17	greg	1.1	#include "rpaint.h"
18
19			#include "random.h"
20	greg	1.7
21	greg	1.13	#ifndef WFLUSH
22	greg	2.4	#ifdef SPEED
23			#define WFLUSH (5*SPEED)
24			#else
25			#define WFLUSH 100 /* flush after this many rays */
26			#endif
27	greg	1.13	#endif
28	greg	1.7
29	greg	2.2	#ifdef SMLFLT
30			#define sscanvec(s,v) (sscanf(s,"%f %f %f",v,v+1,v+2)==3)
31			#else
32			#define sscanvec(s,v) (sscanf(s,"%lf %lf %lf",v,v+1,v+2)==3)
33			#endif
34	greg	1.13
35	greg	2.2
36	greg	1.7	getrect(s, r) /* get a box */
37			char *s;
38			register RECT *r;
39			{
40			int x0, y0, x1, y1;
41
42			if (*s && !strncmp(s, "all", strlen(s))) {
43			r->l = r->d = 0;
44	greg	1.9	r->r = hresolu;
45			r->u = vresolu;
46	greg	1.7	return(0);
47			}
48			if (sscanf(s, "%d %d %d %d", &x0, &y0, &x1, &y1) != 4) {
49			if (dev->getcur == NULL)
50			return(-1);
51			(*dev->comout)("Pick first corner\n");
52			if ((*dev->getcur)(&x0, &y0) == ABORT)
53			return(-1);
54			(*dev->comout)("Pick second corner\n");
55			if ((*dev->getcur)(&x1, &y1) == ABORT)
56			return(-1);
57			}
58			if (x0 < x1) {
59			r->l = x0;
60			r->r = x1;
61			} else {
62			r->l = x1;
63			r->r = x0;
64			}
65			if (y0 < y1) {
66			r->d = y0;
67			r->u = y1;
68			} else {
69			r->d = y1;
70			r->u = y0;
71			}
72			if (r->l < 0) r->l = 0;
73			if (r->d < 0) r->d = 0;
74	greg	1.9	if (r->r > hresolu) r->r = hresolu;
75			if (r->u > vresolu) r->u = vresolu;
76	greg	1.7	if (r->l > r->r) r->l = r->r;
77			if (r->d > r->u) r->d = r->u;
78			return(0);
79			}
80
81
82			getinterest(s, direc, vec, mp) /* get area of interest */
83			char *s;
84			int direc;
85			FVECT vec;
86			double *mp;
87			{
88			int x, y;
89			RAY thisray;
90			register int i;
91
92			if (sscanf(s, "%lf", mp) != 1)
93			*mp = 1.0;
94			else if (mp < -FTINY) / negative zoom is reduction */
95			mp = -1.0 / mp;
96			else if (mp <= FTINY) { / too small */
97			error(COMMAND, "illegal magnification");
98			return(-1);
99			}
100	greg	2.2	if (!sscanvec(sskip(s), vec)) {
101	greg	1.7	if (dev->getcur == NULL)
102			return(-1);
103			(*dev->comout)("Pick view center\n");
104			if ((*dev->getcur)(&x, &y) == ABORT)
105			return(-1);
106	greg	2.6	if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
107			&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
108	greg	1.17	error(COMMAND, "not on image");
109			return(-1);
110			}
111	greg	1.7	if (!direc \|\| ourview.type == VT_PAR) {
112			rayorigin(&thisray, NULL, PRIMARY, 1.0);
113			if (!localhit(&thisray, &thescene)) {
114			error(COMMAND, "not a local object");
115			return(-1);
116			}
117			}
118			if (direc)
119			if (ourview.type == VT_PAR)
120			for (i = 0; i < 3; i++)
121			vec[i] = thisray.rop[i] - ourview.vp[i];
122			else
123			VCOPY(vec, thisray.rdir);
124			else
125			VCOPY(vec, thisray.rop);
126			} else if (direc)
127			for (i = 0; i < 3; i++)
128			vec[i] -= ourview.vp[i];
129			return(0);
130			}
131	greg	1.1
132
133			float * /* keep consistent with COLOR typedef */
134			greyof(col) /* convert color to greyscale */
135			register COLOR col;
136			{
137			static COLOR gcol;
138			double b;
139
140			b = bright(col);
141			setcolor(gcol, b, b, b);
142			return(gcol);
143			}
144
145
146			paint(p, xmin, ymin, xmax, ymax) /* compute and paint a rectangle */
147			register PNODE *p;
148			int xmin, ymin, xmax, ymax;
149			{
150	greg	2.5	extern unsigned long nrays;
151			static unsigned long lastflush = 0;
152	greg	1.1	static RAY thisray;
153			double h, v;
154
155			if (xmax - xmin <= 0 \|\| ymax - ymin <= 0) { /* empty */
156			p->x = xmin;
157			p->y = ymin;
158			setcolor(p->v, 0.0, 0.0, 0.0);
159			return;
160			}
161			/* jitter ray direction */
162	greg	1.15	h = xmin + (xmax-xmin)*frandom();
163			v = ymin + (ymax-ymin)*frandom();
164	greg	1.1
165	greg	2.6	if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir, &ourview,
166			h/hresolu, v/vresolu)) < -FTINY) {
167	greg	1.17	setcolor(thisray.rcol, 0.0, 0.0, 0.0);
168			} else {
169			rayorigin(&thisray, NULL, PRIMARY, 1.0);
170	greg	1.20	samplendx++;
171	greg	1.17	rayvalue(&thisray);
172			}
173	greg	1.1
174	greg	1.15	p->x = h;
175			p->y = v;
176	greg	1.1	copycolor(p->v, thisray.rcol);
177			scalecolor(p->v, exposure);
178
179			(*dev->paintr)(greyscale?greyof(p->v):p->v, xmin, ymin, xmax, ymax);
180	greg	1.13
181			if (dev->flush != NULL && nrays - lastflush >= WFLUSH) {
182			lastflush = nrays;
183			(*dev->flush)();
184			}
185	greg	1.1	}
186
187
188			newimage() /* start a new image */
189			{
190			/* free old image */
191			freepkids(&ptrunk);
192	greg	1.19	/* save reserve memory */
193			fillreserves();
194	greg	1.9	/* compute resolution */
195	greg	1.10	hresolu = dev->xsiz;
196			vresolu = dev->ysiz;
197	greg	1.11	normaspect(viewaspect(&ourview), &dev->pixaspect, &hresolu, &vresolu);
198	greg	1.1	pframe.l = pframe.d = 0;
199	greg	1.9	pframe.r = hresolu; pframe.u = vresolu;
200	greg	1.1	pdepth = 0;
201			/* clear device */
202	greg	1.9	(*dev->clear)(hresolu, vresolu);
203	greg	1.1	/* get first value */
204	greg	1.9	paint(&ptrunk, 0, 0, hresolu, vresolu);
205	greg	1.1	}
206
207
208			redraw() /* redraw the image */
209			{
210	greg	1.9	(*dev->clear)(hresolu, vresolu);
211	greg	1.1	(*dev->comout)("redrawing...\n");
212	greg	1.9	repaint(0, 0, hresolu, vresolu);
213	greg	1.1	(*dev->comout)("\n");
214			}
215
216
217			repaint(xmin, ymin, xmax, ymax) /* repaint a region */
218			int xmin, ymin, xmax, ymax;
219			{
220			RECT reg;
221
222			reg.l = xmin; reg.r = xmax;
223			reg.d = ymin; reg.u = ymax;
224
225	greg	1.9	paintrect(&ptrunk, 0, 0, hresolu, vresolu, &reg);
226	greg	1.1	}
227
228
229			paintrect(p, xmin, ymin, xmax, ymax, r) /* paint picture rectangle */
230			register PNODE *p;
231			int xmin, ymin, xmax, ymax;
232			register RECT *r;
233			{
234			int mx, my;
235
236			if (xmax - xmin <= 0 \|\| ymax - ymin <= 0)
237			return;
238
239			if (p->kid == NULL) {
240			(*dev->paintr)(greyscale?greyof(p->v):p->v,
241			xmin, ymin, xmax, ymax); /* do this */
242			return;
243			}
244			mx = (xmin + xmax) >> 1; /* do kids */
245			my = (ymin + ymax) >> 1;
246			if (mx > r->l) {
247			if (my > r->d)
248			paintrect(p->kid+DL, xmin, ymin, mx, my, r);
249			if (my < r->u)
250			paintrect(p->kid+UL, xmin, my, mx, ymax, r);
251			}
252			if (mx < r->r) {
253			if (my > r->d)
254			paintrect(p->kid+DR, mx, ymin, xmax, my, r);
255			if (my < r->u)
256			paintrect(p->kid+UR, mx, my, xmax, ymax, r);
257			}
258			}
259
260
261			PNODE *
262			findrect(x, y, p, r, pd) /* find a rectangle */
263			int x, y;
264			register PNODE *p;
265			register RECT *r;
266			int pd;
267			{
268			int mx, my;
269
270			while (p->kid != NULL && pd--) {
271
272			mx = (r->l + r->r) >> 1;
273			my = (r->d + r->u) >> 1;
274
275			if (x < mx) {
276			r->r = mx;
277			if (y < my) {
278			r->u = my;
279			p = p->kid+DL;
280			} else {
281			r->d = my;
282			p = p->kid+UL;
283			}
284			} else {
285			r->l = mx;
286			if (y < my) {
287			r->u = my;
288			p = p->kid+DR;
289			} else {
290			r->d = my;
291			p = p->kid+UR;
292			}
293			}
294			}
295			return(p);
296			}
297
298
299			scalepict(p, sf) /* scale picture values */
300			register PNODE *p;
301			double sf;
302			{
303			scalecolor(p->v, sf); /* do this node */
304
305			if (p->kid == NULL)
306			return;
307			/* do children */
308			scalepict(p->kid+DL, sf);
309			scalepict(p->kid+DR, sf);
310			scalepict(p->kid+UL, sf);
311			scalepict(p->kid+UR, sf);
312			}
313
314
315			getpictcolrs(yoff, scan, p, xsiz, ysiz) /* get scanline from picture */
316			int yoff;
317			register COLR *scan;
318			register PNODE *p;
319			int xsiz, ysiz;
320			{
321			register int mx;
322			int my;
323
324			if (p->kid == NULL) { /* do this node */
325			setcolr(scan[0], colval(p->v,RED),
326			colval(p->v,GRN),
327			colval(p->v,BLU));
328			for (mx = 1; mx < xsiz; mx++)
329			copycolr(scan[mx], scan[0]);
330			return;
331			}
332			/* do kids */
333			mx = xsiz >> 1;
334			my = ysiz >> 1;
335			if (yoff < my) {
336			getpictcolrs(yoff, scan, p->kid+DL, mx, my);
337			getpictcolrs(yoff, scan+mx, p->kid+DR, xsiz-mx, my);
338			} else {
339			getpictcolrs(yoff-my, scan, p->kid+UL, mx, ysiz-my);
340			getpictcolrs(yoff-my, scan+mx, p->kid+UR, xsiz-mx, ysiz-my);
341			}
342			}
343
344
345			pcopy(p1, p2) /* copy paint node p1 into p2 */
346			register PNODE p1, p2;
347			{
348			copycolor(p2->v, p1->v);
349			p2->x = p1->x;
350			p2->y = p1->y;
351			}
352
353
354			freepkids(p) /* free pnode's children */
355			register PNODE *p;
356			{
357			if (p->kid == NULL)
358			return;
359			freepkids(p->kid+DL);
360			freepkids(p->kid+DR);
361			freepkids(p->kid+UL);
362			freepkids(p->kid+UR);
363			free((char *)p->kid);
364			p->kid = NULL;
365			}
366
367
368			newview(vp) /* change viewing parameters */
369			register VIEW *vp;
370			{
371			char *err;
372
373	greg	1.6	if ((err = setview(vp)) != NULL) {
374	greg	1.1	sprintf(errmsg, "view not set - %s", err);
375			error(COMMAND, errmsg);
376	greg	1.12	} else if (bcmp((char )vp, (char )&ourview, sizeof(VIEW))) {
377			copystruct(&oldview, &ourview);
378			copystruct(&ourview, vp);
379	greg	1.14	newimage();
380	greg	1.1	}
381			}
382
383
384	greg	1.4	moveview(angle, elev, mag, vc) /* move viewpoint */
385			double angle, elev, mag;
386	greg	1.1	FVECT vc;
387			{
388			double d;
389	greg	1.4	FVECT v1;
390	greg	1.1	VIEW nv;
391			register int i;
392
393			VCOPY(nv.vup, ourview.vup);
394	greg	1.9	nv.hoff = ourview.hoff; nv.voff = ourview.voff;
395	greg	1.1	spinvector(nv.vdir, ourview.vdir, ourview.vup, angle*(PI/180.));
396	greg	1.4	if (elev != 0.0) {
397	greg	1.5	fcross(v1, ourview.vup, nv.vdir);
398	greg	1.4	normalize(v1);
399			spinvector(nv.vdir, nv.vdir, v1, elev*(PI/180.));
400			}
401	greg	1.1	if ((nv.type = ourview.type) == VT_PAR) {
402			nv.horiz = ourview.horiz / mag;
403			nv.vert = ourview.vert / mag;
404	greg	1.3	d = 0.0; /* don't move closer */
405	greg	1.2	for (i = 0; i < 3; i++)
406	greg	1.3	d += (vc[i] - ourview.vp[i])*ourview.vdir[i];
407	greg	2.7	nv.vfore = ourview.vfore;
408			nv.vaft = ourview.vaft;
409	greg	1.1	} else {
410			nv.horiz = ourview.horiz;
411			nv.vert = ourview.vert;
412	greg	1.2	d = sqrt(dist2(ourview.vp, vc)) / mag;
413	greg	2.7	nv.vfore = ourview.vfore + d - d*mag;
414			if (nv.vfore < 0.0) nv.vfore = 0.0;
415			nv.vaft = ourview.vaft + d - d*mag;
416			if (nv.vaft < nv.vfore) nv.vaft = 0.0;
417	greg	1.1	}
418	greg	1.2	for (i = 0; i < 3; i++)
419			nv.vp[i] = vc[i] - d*nv.vdir[i];
420	greg	1.1	newview(&nv);
421	greg	1.17	}
422
423
424			zoomview(vp, zf) /* zoom in our out */
425			register VIEW *vp;
426			double zf;
427			{
428			switch (vp->type) {
429			case VT_PAR: /* parallel view */
430			case VT_ANG: /* angular fisheye */
431			vp->horiz /= zf;
432			vp->vert /= zf;
433			return;
434			case VT_PER: /* perspective view */
435			vp->horiz = atan(tan(vp->horiz*(PI/180./2.))/zf) /
436			(PI/180./2.);
437			vp->vert = atan(tan(vp->vert*(PI/180./2.))/zf) /
438			(PI/180./2.);
439			return;
440			case VT_HEM: /* hemispherical fisheye */
441			vp->horiz = sin(vp->horiz*(PI/180./2.))/zf;
442			if (vp->horiz >= 1.0-FTINY)
443			vp->horiz = 180.;
444			else
445			vp->horiz = asin(vp->horiz) / (PI/180./2.);
446			vp->vert = sin(vp->vert*(PI/180./2.))/zf;
447			if (vp->vert >= 1.0-FTINY)
448			vp->vert = 180.;
449			else
450			vp->vert = asin(vp->vert) / (PI/180./2.);
451			return;
452			}
453	greg	1.1	}