--- /dev/null
+/*
+libanim - hierarchical keyframe animation library
+Copyright (C) 2012-2015 John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published
+by the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include "track.h"
+#include "dynarr.h"
+
+static int keycmp(const void *a, const void *b);
+static int find_prev_key(struct anm_keyframe *arr, int start, int end, anm_time_t tm);
+
+static float interp_step(float v0, float v1, float v2, float v3, float t);
+static float interp_linear(float v0, float v1, float v2, float v3, float t);
+static float interp_cubic(float v0, float v1, float v2, float v3, float t);
+
+static anm_time_t remap_extend(anm_time_t tm, anm_time_t start, anm_time_t end);
+static anm_time_t remap_clamp(anm_time_t tm, anm_time_t start, anm_time_t end);
+static anm_time_t remap_repeat(anm_time_t tm, anm_time_t start, anm_time_t end);
+static anm_time_t remap_pingpong(anm_time_t tm, anm_time_t start, anm_time_t end);
+
+/* XXX keep this in sync with enum anm_interpolator at track.h */
+static float (*interp[])(float, float, float, float, float) = {
+ interp_step,
+ interp_linear,
+ interp_cubic,
+ 0
+};
+
+/* XXX keep this in sync with enum anm_extrapolator at track.h */
+static anm_time_t (*remap_time[])(anm_time_t, anm_time_t, anm_time_t) = {
+ remap_extend,
+ remap_clamp,
+ remap_repeat,
+ remap_pingpong,
+ 0
+};
+
+int anm_init_track(struct anm_track *track)
+{
+ memset(track, 0, sizeof *track);
+
+ if(!(track->keys = dynarr_alloc(0, sizeof *track->keys))) {
+ return -1;
+ }
+ track->interp = ANM_INTERP_LINEAR;
+ track->extrap = ANM_EXTRAP_CLAMP;
+ return 0;
+}
+
+void anm_destroy_track(struct anm_track *track)
+{
+ dynarr_free(track->keys);
+}
+
+struct anm_track *anm_create_track(void)
+{
+ struct anm_track *track;
+
+ if((track = malloc(sizeof *track))) {
+ if(anm_init_track(track) == -1) {
+ free(track);
+ return 0;
+ }
+ }
+ return track;
+}
+
+void anm_free_track(struct anm_track *track)
+{
+ anm_destroy_track(track);
+ free(track);
+}
+
+void anm_copy_track(struct anm_track *dest, const struct anm_track *src)
+{
+ free(dest->name);
+ if(dest->keys) {
+ dynarr_free(dest->keys);
+ }
+
+ if(src->name) {
+ dest->name = malloc(strlen(src->name) + 1);
+ strcpy(dest->name, src->name);
+ }
+
+ dest->count = src->count;
+ dest->keys = dynarr_alloc(src->count, sizeof *dest->keys);
+ memcpy(dest->keys, src->keys, src->count * sizeof *dest->keys);
+
+ dest->def_val = src->def_val;
+ dest->interp = src->interp;
+ dest->extrap = src->extrap;
+}
+
+int anm_set_track_name(struct anm_track *track, const char *name)
+{
+ char *tmp;
+
+ if(!(tmp = malloc(strlen(name) + 1))) {
+ return -1;
+ }
+ free(track->name);
+ track->name = tmp;
+ return 0;
+}
+
+const char *anm_get_track_name(struct anm_track *track)
+{
+ return track->name;
+}
+
+void anm_set_track_interpolator(struct anm_track *track, enum anm_interpolator in)
+{
+ track->interp = in;
+}
+
+void anm_set_track_extrapolator(struct anm_track *track, enum anm_extrapolator ex)
+{
+ track->extrap = ex;
+}
+
+anm_time_t anm_remap_time(struct anm_track *track, anm_time_t tm, anm_time_t start, anm_time_t end)
+{
+ return remap_time[track->extrap](tm, start, end);
+}
+
+void anm_set_track_default(struct anm_track *track, float def)
+{
+ track->def_val = def;
+}
+
+int anm_set_keyframe(struct anm_track *track, struct anm_keyframe *key)
+{
+ int idx = anm_get_key_interval(track, key->time);
+
+ /* if we got a valid keyframe index, compare them... */
+ if(idx >= 0 && idx < track->count && keycmp(key, track->keys + idx) == 0) {
+ /* ... it's the same key, just update the value */
+ track->keys[idx].val = key->val;
+ } else {
+ /* ... it's a new key, add it and re-sort them */
+ void *tmp;
+ if(!(tmp = dynarr_push(track->keys, key))) {
+ return -1;
+ }
+ track->keys = tmp;
+ /* TODO lazy qsort */
+ qsort(track->keys, ++track->count, sizeof *track->keys, keycmp);
+ }
+ return 0;
+}
+
+static int keycmp(const void *a, const void *b)
+{
+ return ((struct anm_keyframe*)a)->time - ((struct anm_keyframe*)b)->time;
+}
+
+struct anm_keyframe *anm_get_keyframe(struct anm_track *track, int idx)
+{
+ if(idx < 0 || idx >= track->count) {
+ return 0;
+ }
+ return track->keys + idx;
+}
+
+int anm_get_key_interval(struct anm_track *track, anm_time_t tm)
+{
+ int last;
+
+ if(!track->count || tm < track->keys[0].time) {
+ return -1;
+ }
+
+ last = track->count - 1;
+ if(tm > track->keys[last].time) {
+ return last;
+ }
+
+ return find_prev_key(track->keys, 0, last, tm);
+}
+
+static int find_prev_key(struct anm_keyframe *arr, int start, int end, anm_time_t tm)
+{
+ int mid;
+
+ if(end - start <= 1) {
+ return start;
+ }
+
+ mid = (start + end) / 2;
+ if(tm < arr[mid].time) {
+ return find_prev_key(arr, start, mid, tm);
+ }
+ if(tm > arr[mid].time) {
+ return find_prev_key(arr, mid, end, tm);
+ }
+ return mid;
+}
+
+int anm_set_value(struct anm_track *track, anm_time_t tm, float val)
+{
+ struct anm_keyframe key;
+ key.time = tm;
+ key.val = val;
+
+ return anm_set_keyframe(track, &key);
+}
+
+float anm_get_value(struct anm_track *track, anm_time_t tm)
+{
+ int idx0, idx1, last_idx;
+ anm_time_t tstart, tend;
+ float t, dt;
+ float v0, v1, v2, v3;
+
+ if(!track->count) {
+ return track->def_val;
+ }
+
+ last_idx = track->count - 1;
+
+ tstart = track->keys[0].time;
+ tend = track->keys[last_idx].time;
+
+ if(tstart == tend) {
+ return track->keys[0].val;
+ }
+
+ tm = remap_time[track->extrap](tm, tstart, tend);
+
+ idx0 = anm_get_key_interval(track, tm);
+ assert(idx0 >= 0 && idx0 < track->count);
+ idx1 = idx0 + 1;
+
+ if(idx0 == last_idx) {
+ return track->keys[idx0].val;
+ }
+
+ dt = (float)(track->keys[idx1].time - track->keys[idx0].time);
+ t = (float)(tm - track->keys[idx0].time) / dt;
+
+ v1 = track->keys[idx0].val;
+ v2 = track->keys[idx1].val;
+
+ /* get the neigboring values to allow for cubic interpolation */
+ v0 = idx0 > 0 ? track->keys[idx0 - 1].val : v1;
+ v3 = idx1 < last_idx ? track->keys[idx1 + 1].val : v2;
+
+ return interp[track->interp](v0, v1, v2, v3, t);
+}
+
+
+static float interp_step(float v0, float v1, float v2, float v3, float t)
+{
+ return v1;
+}
+
+static float interp_linear(float v0, float v1, float v2, float v3, float t)
+{
+ return v1 + (v2 - v1) * t;
+}
+
+static float interp_cubic(float a, float b, float c, float d, float t)
+{
+ float x, y, z, w;
+ float tsq = t * t;
+
+ x = -a + 3.0 * b - 3.0 * c + d;
+ y = 2.0 * a - 5.0 * b + 4.0 * c - d;
+ z = c - a;
+ w = 2.0 * b;
+
+ return 0.5 * (x * tsq * t + y * tsq + z * t + w);
+}
+
+static anm_time_t remap_extend(anm_time_t tm, anm_time_t start, anm_time_t end)
+{
+ return remap_repeat(tm, start, end);
+}
+
+static anm_time_t remap_clamp(anm_time_t tm, anm_time_t start, anm_time_t end)
+{
+ if(start == end) {
+ return start;
+ }
+ return tm < start ? start : (tm >= end ? end : tm);
+}
+
+static anm_time_t remap_repeat(anm_time_t tm, anm_time_t start, anm_time_t end)
+{
+ anm_time_t x, interv = end - start;
+
+ if(interv == 0) {
+ return start;
+ }
+
+ x = (tm - start) % interv;
+ if(x < 0) {
+ x += interv;
+ }
+ return x + start;
+
+ /*if(tm < start) {
+ while(tm < start) {
+ tm += interv;
+ }
+ return tm;
+ }
+ return (tm - start) % interv + start;*/
+}
+
+static anm_time_t remap_pingpong(anm_time_t tm, anm_time_t start, anm_time_t end)
+{
+ anm_time_t interv = end - start;
+ anm_time_t x = remap_repeat(tm, start, end + interv);
+
+ return x > end ? end + interv - x : x;
+}
projects / dosdemo / blobdiff