src/common/cone.c

/* Copyright (c) 1992 Regents of the University of California */

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

/*
 *  cone.c - routines for making cones
 *
 *     2/12/86
 */

#include  "standard.h"

#include  "object.h"

#include  "otypes.h"

#include  "cone.h"

/*
 *     In general, a cone may be any one of a cone, a cylinder, a ring,
 *  a cup (inverted cone), or a tube (inverted cylinder).
 *     Most cones are specified with a starting point and radius and
 *  an ending point and radius.  In the cases of a cylinder or tube,
 *  only one radius is needed.  In the case of a ring, a normal direction
 *  is specified instead of a second endpoint.
 *
 *      mtype (cone|cup) name
 *      0
 *      0
 *      8 P0x P0y P0z P1x P1y P1z R0 R1
 *
 *      mtype (cylinder|tube) name
 *      0
 *      0
 *      7 P0x P0y P0z P1x P1y P1z R
 *
 *      mtype ring name
 *      0
 *      0
 *      8 Px Py Pz Nx Ny Nz R0 R1
 */


CONE *
getcone(o, getxf)                       /* get cone structure */
register OBJREC  *o;
int  getxf;
{
        extern double  sqrt();
        int  sgn0, sgn1;
        register CONE  *co;

        if ((co = (CONE *)o->os) == NULL) {

                co = (CONE *)malloc(sizeof(CONE));
                if (co == NULL)
                        error(SYSTEM, "out of memory in makecone");

                co->ca = o->oargs.farg;
                                                /* get radii */
                if (o->otype == OBJ_CYLINDER | o->otype == OBJ_TUBE) {
                        if (o->oargs.nfargs != 7)
                                goto argcerr;
                        if (co->ca[6] < -FTINY) {
                                objerror(o, WARNING, "negative radius");
                                o->otype = o->otype == OBJ_CYLINDER ?
                                                OBJ_TUBE : OBJ_CYLINDER;
                                co->ca[6] = -co->ca[6];
                        } else if (co->ca[6] <= FTINY)
                                goto raderr;
                        co->p0 = 0; co->p1 = 3;
                        co->r0 = co->r1 = 6;
                } else {
                        if (o->oargs.nfargs != 8)
                                goto argcerr;
                        if (co->ca[6] < -FTINY) sgn0 = -1;
                        else if (co->ca[6] > FTINY) sgn0 = 1;
                        else sgn0 = 0;
                        if (co->ca[7] < -FTINY) sgn1 = -1;
                        else if (co->ca[7] > FTINY) sgn1 = 1;
                        else sgn1 = 0;
                        if (sgn0+sgn1 == 0)
                                goto raderr;
                        if (sgn0 < 0 | sgn1 < 0) {
                                objerror(o, o->otype==OBJ_RING?USER:WARNING,
                                        "negative radii");
                                o->otype = o->otype == OBJ_CONE ?
                                                OBJ_CUP : OBJ_CONE;
                        }
                        co->ca[6] = co->ca[6]*sgn0;
                        co->ca[7] = co->ca[7]*sgn1;
                        if (co->ca[7] - co->ca[6] > FTINY) {
                                if (o->otype == OBJ_RING)
                                        co->p0 = co->p1 = 0;
                                else {
                                        co->p0 = 0; co->p1 = 3;
                                }
                                co->r0 = 6; co->r1 = 7;
                        } else if (co->ca[6] - co->ca[7] > FTINY) {
                                if (o->otype == OBJ_RING)
                                        co->p0 = co->p1 = 0;
                                else {
                                        co->p0 = 3; co->p1 = 0;
                                }
                                co->r0 = 7; co->r1 = 6;
                        } else {
                                if (o->otype == OBJ_RING)
                                        goto raderr;
                                o->otype = o->otype == OBJ_CONE ?
                                                OBJ_CYLINDER : OBJ_TUBE;
                                o->oargs.nfargs = 7;
                                co->p0 = 0; co->p1 = 3;
                                co->r0 = co->r1 = 6;
                        }
                }
                                                /* get axis orientation */
                if (o->otype == OBJ_RING)
                        VCOPY(co->ad, o->oargs.farg+3);
                else {
                        co->ad[0] = CO_P1(co)[0] - CO_P0(co)[0];
                        co->ad[1] = CO_P1(co)[1] - CO_P0(co)[1];
                        co->ad[2] = CO_P1(co)[2] - CO_P0(co)[2];
                }
                co->al = normalize(co->ad);
                if (co->al == 0.0)
                        objerror(o, USER, "zero orientation");
                                        /* compute axis and side lengths */
                if (o->otype == OBJ_RING) {
                        co->al = 0.0;
                        co->sl = CO_R1(co) - CO_R0(co);
                } else if (o->otype == OBJ_CONE | o->otype == OBJ_CUP) {
                        co->sl = co->ca[7] - co->ca[6];
                        co->sl = sqrt(co->sl*co->sl + co->al*co->al);
                } else { /* OBJ_CYLINDER or OBJ_TUBE */
                        co->sl = co->al;
                }
                co->tm = NULL;
                o->os = (char *)co;
        }
        if (getxf && co->tm == NULL)
                conexform(co);
        return(co);

argcerr:
        objerror(o, USER, "bad # arguments");
raderr:
        objerror(o, USER, "illegal radii");
}


freecone(o)                     /* free memory associated with cone */
OBJREC  *o;
{
        register CONE  *co = (CONE *)o->os;

        if (o->os == NULL)
                return;
        if (co->tm != NULL)
                free((char *)co->tm);
        free(o->os);
        o->os = NULL;
}


conexform(co)                   /* get cone transformation matrix */
register CONE  *co;
{
        extern double  sqrt();
        MAT4  m4;
        register double  d;
        register int  i;

        co->tm = (FLOAT (*)[4])malloc(sizeof(MAT4));
        if (co->tm == NULL)
                error(SYSTEM, "out of memory in conexform");

                                /* translate to origin */
        setident4(co->tm);
        if (co->r0 == co->r1)
                d = 0.0;
        else
                d = CO_R0(co) / (CO_R1(co) - CO_R0(co));
        for (i = 0; i < 3; i++)
                co->tm[3][i] = d*(CO_P1(co)[i] - CO_P0(co)[i])
                                - CO_P0(co)[i];
        
                                /* rotate to positive z-axis */
        setident4(m4);
        d = co->ad[1]*co->ad[1] + co->ad[2]*co->ad[2];
        if (d <= FTINY*FTINY) {
                m4[0][0] = 0.0;
                m4[0][2] = co->ad[0];
                m4[2][0] = -co->ad[0];
                m4[2][2] = 0.0;
        } else {
                d = sqrt(d);
                m4[0][0] = d;
                m4[1][0] = -co->ad[0]*co->ad[1]/d;
                m4[2][0] = -co->ad[0]*co->ad[2]/d;
                m4[1][1] = co->ad[2]/d;
                m4[2][1] = -co->ad[1]/d;
                m4[0][2] = co->ad[0];
                m4[1][2] = co->ad[1];
                m4[2][2] = co->ad[2];
        }
        multmat4(co->tm, co->tm, m4);

                                /* scale z-axis */
        if (co->p0 != co->p1 & co->r0 != co->r1) {
                setident4(m4);
                m4[2][2] = (CO_R1(co) - CO_R0(co)) / co->al;
                multmat4(co->tm, co->tm, m4);
        }
}
Revision:	2.2
Committed:	Sun Sep 6 11:53:47 1992 UTC (31 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.1:	+39 -33 lines
Log Message:	major aesthetic changes -- made R0 always smaller than R1
#	Content
1	/* Copyright (c) 1992 Regents of the University of California */
2
3	#ifndef lint
4	static char SCCSid[] = "$SunId$ LBL";
5	#endif
6
7	/*
8	* cone.c - routines for making cones
9	*
10	* 2/12/86
11	*/
12
13	#include "standard.h"
14
15	#include "object.h"
16
17	#include "otypes.h"
18
19	#include "cone.h"
20
21	/*
22	* In general, a cone may be any one of a cone, a cylinder, a ring,
23	* a cup (inverted cone), or a tube (inverted cylinder).
24	* Most cones are specified with a starting point and radius and
25	* an ending point and radius. In the cases of a cylinder or tube,
26	* only one radius is needed. In the case of a ring, a normal direction
27	* is specified instead of a second endpoint.
28	*
29	* mtype (cone\|cup) name
30	* 0
31	* 0
32	* 8 P0x P0y P0z P1x P1y P1z R0 R1
33	*
34	* mtype (cylinder\|tube) name
35	* 0
36	* 0
37	* 7 P0x P0y P0z P1x P1y P1z R
38	*
39	* mtype ring name
40	* 0
41	* 0
42	* 8 Px Py Pz Nx Ny Nz R0 R1
43	*/
44
45
46	CONE *
47	getcone(o, getxf) /* get cone structure */
48	register OBJREC *o;
49	int getxf;
50	{
51	extern double sqrt();
52	int sgn0, sgn1;
53	register CONE *co;
54
55	if ((co = (CONE *)o->os) == NULL) {
56
57	co = (CONE *)malloc(sizeof(CONE));
58	if (co == NULL)
59	error(SYSTEM, "out of memory in makecone");
60
61	co->ca = o->oargs.farg;
62	/* get radii */
63	if (o->otype == OBJ_CYLINDER \| o->otype == OBJ_TUBE) {
64	if (o->oargs.nfargs != 7)
65	goto argcerr;
66	if (co->ca[6] < -FTINY) {
67	objerror(o, WARNING, "negative radius");
68	o->otype = o->otype == OBJ_CYLINDER ?
69	OBJ_TUBE : OBJ_CYLINDER;
70	co->ca[6] = -co->ca[6];
71	} else if (co->ca[6] <= FTINY)
72	goto raderr;
73	co->p0 = 0; co->p1 = 3;
74	co->r0 = co->r1 = 6;
75	} else {
76	if (o->oargs.nfargs != 8)
77	goto argcerr;
78	if (co->ca[6] < -FTINY) sgn0 = -1;
79	else if (co->ca[6] > FTINY) sgn0 = 1;
80	else sgn0 = 0;
81	if (co->ca[7] < -FTINY) sgn1 = -1;
82	else if (co->ca[7] > FTINY) sgn1 = 1;
83	else sgn1 = 0;
84	if (sgn0+sgn1 == 0)
85	goto raderr;
86	if (sgn0 < 0 \| sgn1 < 0) {
87	objerror(o, o->otype==OBJ_RING?USER:WARNING,
88	"negative radii");
89	o->otype = o->otype == OBJ_CONE ?
90	OBJ_CUP : OBJ_CONE;
91	}
92	co->ca[6] = co->ca[6]*sgn0;
93	co->ca[7] = co->ca[7]*sgn1;
94	if (co->ca[7] - co->ca[6] > FTINY) {
95	if (o->otype == OBJ_RING)
96	co->p0 = co->p1 = 0;
97	else {
98	co->p0 = 0; co->p1 = 3;
99	}
100	co->r0 = 6; co->r1 = 7;
101	} else if (co->ca[6] - co->ca[7] > FTINY) {
102	if (o->otype == OBJ_RING)
103	co->p0 = co->p1 = 0;
104	else {
105	co->p0 = 3; co->p1 = 0;
106	}
107	co->r0 = 7; co->r1 = 6;
108	} else {
109	if (o->otype == OBJ_RING)
110	goto raderr;
111	o->otype = o->otype == OBJ_CONE ?
112	OBJ_CYLINDER : OBJ_TUBE;
113	o->oargs.nfargs = 7;
114	co->p0 = 0; co->p1 = 3;
115	co->r0 = co->r1 = 6;
116	}
117	}
118	/* get axis orientation */
119	if (o->otype == OBJ_RING)
120	VCOPY(co->ad, o->oargs.farg+3);
121	else {
122	co->ad[0] = CO_P1(co)[0] - CO_P0(co)[0];
123	co->ad[1] = CO_P1(co)[1] - CO_P0(co)[1];
124	co->ad[2] = CO_P1(co)[2] - CO_P0(co)[2];
125	}
126	co->al = normalize(co->ad);
127	if (co->al == 0.0)
128	objerror(o, USER, "zero orientation");
129	/* compute axis and side lengths */
130	if (o->otype == OBJ_RING) {
131	co->al = 0.0;
132	co->sl = CO_R1(co) - CO_R0(co);
133	} else if (o->otype == OBJ_CONE \| o->otype == OBJ_CUP) {
134	co->sl = co->ca[7] - co->ca[6];
135	co->sl = sqrt(co->slco->sl + co->alco->al);
136	} else { /* OBJ_CYLINDER or OBJ_TUBE */
137	co->sl = co->al;
138	}
139	co->tm = NULL;
140	o->os = (char *)co;
141	}
142	if (getxf && co->tm == NULL)
143	conexform(co);
144	return(co);
145
146	argcerr:
147	objerror(o, USER, "bad # arguments");
148	raderr:
149	objerror(o, USER, "illegal radii");
150	}
151
152
153	freecone(o) /* free memory associated with cone */
154	OBJREC *o;
155	{
156	register CONE co = (CONE )o->os;
157
158	if (o->os == NULL)
159	return;
160	if (co->tm != NULL)
161	free((char *)co->tm);
162	free(o->os);
163	o->os = NULL;
164	}
165
166
167	conexform(co) /* get cone transformation matrix */
168	register CONE *co;
169	{
170	extern double sqrt();
171	MAT4 m4;
172	register double d;
173	register int i;
174
175	co->tm = (FLOAT (*)[4])malloc(sizeof(MAT4));
176	if (co->tm == NULL)
177	error(SYSTEM, "out of memory in conexform");
178
179	/* translate to origin */
180	setident4(co->tm);
181	if (co->r0 == co->r1)
182	d = 0.0;
183	else
184	d = CO_R0(co) / (CO_R1(co) - CO_R0(co));
185	for (i = 0; i < 3; i++)
186	co->tm[3][i] = d*(CO_P1(co)[i] - CO_P0(co)[i])
187	- CO_P0(co)[i];
188
189	/* rotate to positive z-axis */
190	setident4(m4);
191	d = co->ad[1]co->ad[1] + co->ad[2]co->ad[2];
192	if (d <= FTINY*FTINY) {
193	m4[0][0] = 0.0;
194	m4[0][2] = co->ad[0];
195	m4[2][0] = -co->ad[0];
196	m4[2][2] = 0.0;
197	} else {
198	d = sqrt(d);
199	m4[0][0] = d;
200	m4[1][0] = -co->ad[0]*co->ad[1]/d;
201	m4[2][0] = -co->ad[0]*co->ad[2]/d;
202	m4[1][1] = co->ad[2]/d;
203	m4[2][1] = -co->ad[1]/d;
204	m4[0][2] = co->ad[0];
205	m4[1][2] = co->ad[1];
206	m4[2][2] = co->ad[2];
207	}
208	multmat4(co->tm, co->tm, m4);
209
210	/* scale z-axis */
211	if (co->p0 != co->p1 & co->r0 != co->r1) {
212	setident4(m4);
213	m4[2][2] = (CO_R1(co) - CO_R0(co)) / co->al;
214	multmat4(co->tm, co->tm, m4);
215	}
216	}