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/* xscreensaver, Copyright (c) 1998-2002 Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
#ifndef __ROTATOR_H__
#define __ROTATOR_H__
typedef struct rotator rotator;
/* Returns a rotator object, which encapsulates rotation and motion state.
spin_[xyz]_speed indicates the relative speed of rotation.
Specify 0 if you don't want any rotation around that axis.
spin_accel specifies a scaling factor for the acceleration that is
randomly applied to spin: if you want the speed to change faster,
make this > 1.
wander_speed indicates the relative speed through space.
If randomize_initial_state_p is true, then the initial position and
rotation will be randomized (even if the spin speeds are 0.) If it
is false, then all values will be initially zeroed.
*/
extern rotator *make_rotator (double spin_x_speed,
double spin_y_speed,
double spin_z_speed,
double spin_accel,
double wander_speed,
int randomize_initial_state_p);
/* Rotates one step, and returns the new rotation values.
x, y, and z range from 0.0-1.0, the fraction through the circle
(*not* radians or degrees!)
If `update_p' is non-zero, then (maybe) rotate first.
*/
extern void get_rotation (rotator *rot,
double *x_ret, double *y_ret, double *z_ret,
int update_p);
/* Moves one step, and returns the new position values.
x, y, and z range from 0.0-1.0, the fraction through space:
scale those values as needed.
If `update_p' is non-zero, then (maybe) move first.
*/
extern void get_position (rotator *rot,
double *x_ret, double *y_ret, double *z_ret,
int update_p);
/* Destroys and frees a `rotator' object. */
extern void free_rotator (rotator *r);
#endif /* __ROTATOR_H__ */
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