libanim

annotate src/track.h @ 49:fb9659ca5cf2

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added ping-pong extrapolator
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 13 Apr 2013 07:27:32 +0300
parents f561282b13e8
children 821411647b40
rev   line source
nuclear@0 1 /* An animation track defines the values of a single scalar over time
nuclear@0 2 * and supports various interpolation and extrapolation modes.
nuclear@0 3 */
nuclear@0 4 #ifndef LIBANIM_TRACK_H_
nuclear@0 5 #define LIBANIM_TRACK_H_
nuclear@0 6
nuclear@0 7 #include <limits.h>
nuclear@0 8 #include "config.h"
nuclear@0 9
nuclear@0 10 enum anm_interpolator {
nuclear@0 11 ANM_INTERP_STEP,
nuclear@0 12 ANM_INTERP_LINEAR,
nuclear@0 13 ANM_INTERP_CUBIC
nuclear@0 14 };
nuclear@0 15
nuclear@0 16 enum anm_extrapolator {
nuclear@0 17 ANM_EXTRAP_EXTEND, /* extend to infinity */
nuclear@0 18 ANM_EXTRAP_CLAMP, /* clamp to last value */
nuclear@12 19 ANM_EXTRAP_REPEAT, /* repeat motion */
nuclear@12 20 ANM_EXTRAP_PINGPONG /* repeat with mirroring */
nuclear@0 21 };
nuclear@0 22
nuclear@0 23 typedef long anm_time_t;
nuclear@0 24 #define ANM_TIME_INVAL LONG_MIN
nuclear@0 25
nuclear@0 26 #define ANM_SEC2TM(x) ((anm_time_t)((x) * 1000))
nuclear@0 27 #define ANM_MSEC2TM(x) ((anm_time_t)(x))
nuclear@0 28 #define ANM_TM2SEC(x) ((x) / 1000.0)
nuclear@0 29 #define ANM_TM2MSEC(x) (x)
nuclear@0 30
nuclear@0 31 struct anm_keyframe {
nuclear@0 32 anm_time_t time;
nuclear@0 33 float val;
nuclear@0 34 };
nuclear@0 35
nuclear@0 36 struct anm_track {
nuclear@0 37 char *name;
nuclear@0 38 int count;
nuclear@0 39 struct anm_keyframe *keys;
nuclear@0 40
nuclear@0 41 float def_val;
nuclear@0 42
nuclear@0 43 enum anm_interpolator interp;
nuclear@0 44 enum anm_extrapolator extrap;
nuclear@0 45 };
nuclear@0 46
nuclear@0 47 #ifdef __cplusplus
nuclear@0 48 extern "C" {
nuclear@0 49 #endif
nuclear@0 50
nuclear@0 51 /* track constructor and destructor */
nuclear@0 52 int anm_init_track(struct anm_track *track);
nuclear@0 53 void anm_destroy_track(struct anm_track *track);
nuclear@0 54
nuclear@0 55 /* helper functions that use anm_init_track and anm_destroy_track internally */
nuclear@0 56 struct anm_track *anm_create_track(void);
nuclear@0 57 void anm_free_track(struct anm_track *track);
nuclear@0 58
nuclear@2 59 /* copies track src to dest
nuclear@2 60 * XXX: dest must have been initialized first
nuclear@2 61 */
nuclear@2 62 void anm_copy_track(struct anm_track *dest, struct anm_track *src);
nuclear@2 63
nuclear@0 64 int anm_set_track_name(struct anm_track *track, const char *name);
nuclear@0 65 const char *anm_get_track_name(struct anm_track *track);
nuclear@0 66
nuclear@0 67 void anm_set_track_interpolator(struct anm_track *track, enum anm_interpolator in);
nuclear@0 68 void anm_set_track_extrapolator(struct anm_track *track, enum anm_extrapolator ex);
nuclear@0 69
nuclear@0 70 anm_time_t anm_remap_time(struct anm_track *track, anm_time_t tm, anm_time_t start, anm_time_t end);
nuclear@0 71
nuclear@0 72 void anm_set_track_default(struct anm_track *track, float def);
nuclear@0 73
nuclear@0 74 /* set or update a keyframe */
nuclear@0 75 int anm_set_keyframe(struct anm_track *track, struct anm_keyframe *key);
nuclear@0 76
nuclear@0 77 /* get the idx-th keyframe, returns null if it doesn't exist */
nuclear@0 78 struct anm_keyframe *anm_get_keyframe(struct anm_track *track, int idx);
nuclear@0 79
nuclear@0 80 /* Finds the 0-based index of the intra-keyframe interval which corresponds
nuclear@0 81 * to the specified time. If the time falls exactly onto the N-th keyframe
nuclear@0 82 * the function returns N.
nuclear@0 83 *
nuclear@0 84 * Special cases:
nuclear@0 85 * - if the time is before the first keyframe -1 is returned.
nuclear@0 86 * - if the time is after the last keyframe, the index of the last keyframe
nuclear@0 87 * is returned.
nuclear@0 88 */
nuclear@0 89 int anm_get_key_interval(struct anm_track *track, anm_time_t tm);
nuclear@0 90
nuclear@0 91 int anm_set_value(struct anm_track *track, anm_time_t tm, float val);
nuclear@0 92
nuclear@0 93 /* evaluates and returns the value of the track for a particular time */
nuclear@0 94 float anm_get_value(struct anm_track *track, anm_time_t tm);
nuclear@0 95
nuclear@0 96 #ifdef __cplusplus
nuclear@0 97 }
nuclear@0 98 #endif
nuclear@0 99
nuclear@0 100
nuclear@0 101 #endif /* LIBANIM_TRACK_H_ */