1 /*
2 ===========================================================================
3 Copyright (C) 1997-2006 Id Software, Inc.
4
5 This file is part of Quake 2 Tools source code.
6
7 Quake 2 Tools source code is free software; you can redistribute it
8 and/or modify it under the terms of the GNU General Public License as
9 published by the Free Software Foundation; either version 2 of the License,
10 or (at your option) any later version.
11
12 Quake 2 Tools source code is distributed in the hope that it will be
13 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with Quake 2 Tools source code; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 ===========================================================================
21 */
22
23 // mathlib.c -- math primitives
24
25 #include "cmdlib.h"
26 #include "mathlib.h"
27
28 vec3_t vec3_origin = {0.0f,0.0f,0.0f};
29
30
VectorLength(vec3_t v)31 float VectorLength(vec3_t v)
32 {
33 int i;
34 float length;
35
36 length = 0.0f;
37 for (i=0 ; i< 3 ; i++)
38 length += v[i]*v[i];
39 length = (float)sqrt (length);
40
41 return length;
42 }
43
VectorCompare(vec3_t v1,vec3_t v2)44 qboolean VectorCompare (vec3_t v1, vec3_t v2)
45 {
46 int i;
47
48 for (i=0 ; i<3 ; i++)
49 if (fabs(v1[i]-v2[i]) > EQUAL_EPSILON)
50 return false;
51
52 return true;
53 }
54
Q_rint(vec_t in)55 vec_t Q_rint (vec_t in)
56 {
57 return (float)floor (in + 0.5);
58 }
59
VectorMA(vec3_t va,float scale,vec3_t vb,vec3_t vc)60 void VectorMA (vec3_t va, float scale, vec3_t vb, vec3_t vc)
61 {
62 vc[0] = va[0] + scale*vb[0];
63 vc[1] = va[1] + scale*vb[1];
64 vc[2] = va[2] + scale*vb[2];
65 }
66
CrossProduct(vec3_t v1,vec3_t v2,vec3_t cross)67 void CrossProduct (vec3_t v1, vec3_t v2, vec3_t cross)
68 {
69 cross[0] = v1[1]*v2[2] - v1[2]*v2[1];
70 cross[1] = v1[2]*v2[0] - v1[0]*v2[2];
71 cross[2] = v1[0]*v2[1] - v1[1]*v2[0];
72 }
73
_DotProduct(vec3_t v1,vec3_t v2)74 vec_t _DotProduct (vec3_t v1, vec3_t v2)
75 {
76 return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2];
77 }
78
_VectorSubtract(vec3_t va,vec3_t vb,vec3_t out)79 void _VectorSubtract (vec3_t va, vec3_t vb, vec3_t out)
80 {
81 out[0] = va[0]-vb[0];
82 out[1] = va[1]-vb[1];
83 out[2] = va[2]-vb[2];
84 }
85
_VectorAdd(vec3_t va,vec3_t vb,vec3_t out)86 void _VectorAdd (vec3_t va, vec3_t vb, vec3_t out)
87 {
88 out[0] = va[0]+vb[0];
89 out[1] = va[1]+vb[1];
90 out[2] = va[2]+vb[2];
91 }
92
_VectorCopy(vec3_t in,vec3_t out)93 void _VectorCopy (vec3_t in, vec3_t out)
94 {
95 out[0] = in[0];
96 out[1] = in[1];
97 out[2] = in[2];
98 }
99
VectorNormalize(vec3_t v)100 vec_t VectorNormalize (vec3_t v)
101 {
102 int i;
103 float length;
104
105 length = 0.0f;
106 for (i=0 ; i< 3 ; i++)
107 length += v[i]*v[i];
108 length = (float)sqrt (length);
109 if (length == 0)
110 return (vec_t)0;
111
112 for (i=0 ; i< 3 ; i++)
113 v[i] /= length;
114
115 return length;
116 }
117
VectorInverse(vec3_t v)118 void VectorInverse (vec3_t v)
119 {
120 v[0] = -v[0];
121 v[1] = -v[1];
122 v[2] = -v[2];
123 }
124
VectorScale(vec3_t v,vec_t scale,vec3_t out)125 void VectorScale (vec3_t v, vec_t scale, vec3_t out)
126 {
127 out[0] = v[0] * scale;
128 out[1] = v[1] * scale;
129 out[2] = v[2] * scale;
130 }
131
132