Last change
on this file since 9483 was 732, checked in by tbretz, 24 years ago |
*** empty log message ***
|
-
Property svn:executable
set to
*
|
File size:
906 bytes
|
Line | |
---|
1 | #include "slalib.h"
|
---|
2 | #include "slamac.h"
|
---|
3 | void slaVn ( float v[3], float uv[3], float *vm )
|
---|
4 | /*
|
---|
5 | ** - - - - - -
|
---|
6 | ** s l a V n
|
---|
7 | ** - - - - - -
|
---|
8 | **
|
---|
9 | ** Normalizes a 3-vector also giving the modulus.
|
---|
10 | **
|
---|
11 | ** (single precision)
|
---|
12 | **
|
---|
13 | ** Given:
|
---|
14 | ** v float[3] vector
|
---|
15 | **
|
---|
16 | ** Returned:
|
---|
17 | ** uv float[3] unit vector in direction of v
|
---|
18 | ** *vm float modulus of v
|
---|
19 | **
|
---|
20 | ** Note: v and uv may be the same array.
|
---|
21 | **
|
---|
22 | ** If the modulus of v is zero, uv is set to zero as well.
|
---|
23 | **
|
---|
24 | ** Last revision: 6 November 1999
|
---|
25 | **
|
---|
26 | ** Copyright P.T.Wallace. All rights reserved.
|
---|
27 | */
|
---|
28 | {
|
---|
29 | int i;
|
---|
30 | float w1, w2;
|
---|
31 |
|
---|
32 | /* Modulus */
|
---|
33 | w1 = 0.0f;
|
---|
34 | for ( i = 0; i < 3; i++ ) {
|
---|
35 | w2 = v[i];
|
---|
36 | w1 = w1 + w2 * w2;
|
---|
37 | }
|
---|
38 | w1 = (float) sqrt ( w1 );
|
---|
39 | *vm = w1;
|
---|
40 |
|
---|
41 | /* Normalize the vector */
|
---|
42 | if ( w1 <= 0.0f ) {
|
---|
43 | w1 = 1.0f;
|
---|
44 | }
|
---|
45 | for ( i = 0; i < 3; i++ ) {
|
---|
46 | uv[i] = v[i] / w1;
|
---|
47 | }
|
---|
48 | }
|
---|
Note:
See
TracBrowser
for help on using the repository browser.