| 1 |
/* Copyright (c) 1986 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 |
double fabs(), sqrt(); |
| 52 |
register CONE *co; |
| 53 |
|
| 54 |
if ((co = (CONE *)o->os) == NULL) { |
| 55 |
|
| 56 |
co = (CONE *)malloc(sizeof(CONE)); |
| 57 |
if (co == NULL) |
| 58 |
error(SYSTEM, "out of memory in makecone"); |
| 59 |
|
| 60 |
co->ca = o->oargs.farg; |
| 61 |
/* get radii */ |
| 62 |
if (o->otype == OBJ_CYLINDER || o->otype == OBJ_TUBE) { |
| 63 |
if (o->oargs.nfargs != 7) |
| 64 |
goto argcerr; |
| 65 |
if (co->ca[6] <= FTINY) |
| 66 |
goto raderr; |
| 67 |
co->r0 = co->r1 = 6; |
| 68 |
} else { |
| 69 |
if (o->oargs.nfargs != 8) |
| 70 |
goto argcerr; |
| 71 |
if (co->ca[6] < 0.0 || co->ca[7] < 0.0) |
| 72 |
goto raderr; |
| 73 |
if (fabs(co->ca[7] - co->ca[6]) <= FTINY) |
| 74 |
goto raderr; |
| 75 |
co->r0 = 6; |
| 76 |
co->r1 = 7; |
| 77 |
} |
| 78 |
/* get axis orientation */ |
| 79 |
co->p0 = 0; |
| 80 |
if (o->otype == OBJ_RING) { |
| 81 |
if (co->ca[6] > co->ca[7]) { /* make r0 smaller */ |
| 82 |
co->r0 = 7; |
| 83 |
co->r1 = 6; |
| 84 |
} |
| 85 |
co->p1 = 0; |
| 86 |
VCOPY(co->ad, o->oargs.farg+3); |
| 87 |
} else { |
| 88 |
co->p1 = 3; |
| 89 |
co->ad[0] = co->ca[3] - co->ca[0]; |
| 90 |
co->ad[1] = co->ca[4] - co->ca[1]; |
| 91 |
co->ad[2] = co->ca[5] - co->ca[2]; |
| 92 |
} |
| 93 |
co->al = normalize(co->ad); |
| 94 |
if (co->al == 0.0) |
| 95 |
objerror(o, USER, "zero orientation"); |
| 96 |
/* compute axis and side lengths */ |
| 97 |
if (o->otype == OBJ_RING) { |
| 98 |
co->al = 0.0; |
| 99 |
co->sl = co->ca[co->r1] - co->ca[co->r0]; |
| 100 |
} else if (o->otype == OBJ_CONE || o->otype == OBJ_CUP) { |
| 101 |
co->sl = co->ca[7] - co->ca[6]; |
| 102 |
co->sl = sqrt(co->sl*co->sl + co->al*co->al); |
| 103 |
} else { /* OBJ_CYLINDER || OBJ_TUBE */ |
| 104 |
co->sl = co->al; |
| 105 |
} |
| 106 |
co->tm = NULL; |
| 107 |
(CONE *)o->os = co; |
| 108 |
} |
| 109 |
if (getxf && co->tm == NULL) |
| 110 |
conexform(co); |
| 111 |
return(co); |
| 112 |
|
| 113 |
argcerr: |
| 114 |
objerror(o, USER, "bad # arguments"); |
| 115 |
raderr: |
| 116 |
objerror(o, USER, "illegal radii"); |
| 117 |
} |
| 118 |
|
| 119 |
|
| 120 |
freecone(o) /* free memory associated with cone */ |
| 121 |
OBJREC *o; |
| 122 |
{ |
| 123 |
register CONE *co = (CONE *)o->os; |
| 124 |
|
| 125 |
if (co->tm != NULL) |
| 126 |
free((char *)co->tm); |
| 127 |
free(o->os); |
| 128 |
o->os = NULL; |
| 129 |
} |
| 130 |
|
| 131 |
|
| 132 |
conexform(co) /* get cone transformation matrix */ |
| 133 |
register CONE *co; |
| 134 |
{ |
| 135 |
double sqrt(), fabs(); |
| 136 |
double m4[4][4]; |
| 137 |
register double d; |
| 138 |
register int i; |
| 139 |
|
| 140 |
co->tm = (double (*)[4])malloc(sizeof(m4)); |
| 141 |
if (co->tm == NULL) |
| 142 |
error(SYSTEM, "out of memory in conexform"); |
| 143 |
|
| 144 |
/* translate to origin */ |
| 145 |
setident4(co->tm); |
| 146 |
if (co->r0 == co->r1) |
| 147 |
d = 0.0; |
| 148 |
else |
| 149 |
d = co->ca[co->r0] / (co->ca[co->r1] - co->ca[co->r0]); |
| 150 |
for (i = 0; i < 3; i++) |
| 151 |
co->tm[3][i] = d*(co->ca[co->p1+i] - co->ca[co->p0+i]) |
| 152 |
- co->ca[co->p0+i]; |
| 153 |
|
| 154 |
/* rotate to positive z-axis */ |
| 155 |
setident4(m4); |
| 156 |
d = co->ad[1]*co->ad[1] + co->ad[2]*co->ad[2]; |
| 157 |
if (d <= FTINY*FTINY) { |
| 158 |
m4[0][0] = 0.0; |
| 159 |
m4[0][2] = co->ad[0]; |
| 160 |
m4[2][0] = -co->ad[0]; |
| 161 |
m4[2][2] = 0.0; |
| 162 |
} else { |
| 163 |
d = sqrt(d); |
| 164 |
m4[0][0] = d; |
| 165 |
m4[1][0] = -co->ad[0]*co->ad[1]/d; |
| 166 |
m4[2][0] = -co->ad[0]*co->ad[2]/d; |
| 167 |
m4[1][1] = co->ad[2]/d; |
| 168 |
m4[2][1] = -co->ad[1]/d; |
| 169 |
m4[0][2] = co->ad[0]; |
| 170 |
m4[1][2] = co->ad[1]; |
| 171 |
m4[2][2] = co->ad[2]; |
| 172 |
} |
| 173 |
multmat4(co->tm, co->tm, m4); |
| 174 |
|
| 175 |
/* scale z-axis */ |
| 176 |
setident4(m4); |
| 177 |
if (co->p0 != co->p1 && co->r0 != co->r1) { |
| 178 |
d = fabs(co->ca[co->r1] - co->ca[co->r0]); |
| 179 |
m4[2][2] = d/co->al; |
| 180 |
} |
| 181 |
multmat4(co->tm, co->tm, m4); |
| 182 |
} |
