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
#	User	Rev	Content
1	greg	2.2	/* 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			* 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	greg	2.2	extern double sqrt();
52	greg	1.4	int sgn0, sgn1;
53	greg	1.1	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	greg	2.2	if (o->otype == OBJ_CYLINDER \| o->otype == OBJ_TUBE) {
64	greg	1.1	if (o->oargs.nfargs != 7)
65			goto argcerr;
66	greg	1.4	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	greg	1.1	goto raderr;
73	greg	2.2	co->p0 = 0; co->p1 = 3;
74	greg	1.1	co->r0 = co->r1 = 6;
75			} else {
76			if (o->oargs.nfargs != 8)
77			goto argcerr;
78	greg	1.4	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	greg	1.1	goto raderr;
86	greg	2.2	if (sgn0 < 0 \| sgn1 < 0) {
87	greg	1.4	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	greg	2.2	if (co->ca[7] - co->ca[6] > FTINY) {
95	greg	1.4	if (o->otype == OBJ_RING)
96	greg	2.2	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	greg	1.4	goto raderr;
111			o->otype = o->otype == OBJ_CONE ?
112			OBJ_CYLINDER : OBJ_TUBE;
113			o->oargs.nfargs = 7;
114	greg	2.2	co->p0 = 0; co->p1 = 3;
115			co->r0 = co->r1 = 6;
116	greg	1.4	}
117	greg	1.1	}
118			/* get axis orientation */
119	greg	2.2	if (o->otype == OBJ_RING)
120	greg	1.1	VCOPY(co->ad, o->oargs.farg+3);
121	greg	2.2	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	greg	1.1	}
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	greg	2.2	co->sl = CO_R1(co) - CO_R0(co);
133			} else if (o->otype == OBJ_CONE \| o->otype == OBJ_CUP) {
134	greg	1.1	co->sl = co->ca[7] - co->ca[6];
135			co->sl = sqrt(co->slco->sl + co->alco->al);
136	greg	2.2	} else { /* OBJ_CYLINDER or OBJ_TUBE */
137	greg	1.1	co->sl = co->al;
138			}
139			co->tm = NULL;
140	greg	1.2	o->os = (char *)co;
141	greg	1.1	}
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	greg	1.5	if (o->os == NULL)
159			return;
160	greg	1.1	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	greg	2.2	extern double sqrt();
171	greg	1.6	MAT4 m4;
172	greg	1.1	register double d;
173			register int i;
174
175	greg	2.2	co->tm = (FLOAT (*)[4])malloc(sizeof(MAT4));
176	greg	1.1	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	greg	2.2	d = CO_R0(co) / (CO_R1(co) - CO_R0(co));
185	greg	1.1	for (i = 0; i < 3; i++)
186	greg	2.2	co->tm[3][i] = d*(CO_P1(co)[i] - CO_P0(co)[i])
187			- CO_P0(co)[i];
188	greg	1.1
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	greg	2.2	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	greg	1.1	}
216			}