anim_sys.c

Go to the documentation of this file.

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2009 Blender Foundation, Joshua Leung
 * All rights reserved.
 */
 
#include <float.h>
#include <math.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
 
#include "MEM_guardedalloc.h"
 
#include "BLI_alloca.h"
#include "BLI_blenlib.h"
#include "BLI_dynstr.h"
#include "BLI_listbase.h"
#include "BLI_math_rotation.h"
#include "BLI_math_vector.h"
#include "BLI_string_utils.h"
#include "BLI_utildefines.h"
 
#include "BLT_translation.h"
 
#include "DNA_anim_types.h"
#include "DNA_light_types.h"
#include "DNA_material_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_screen_types.h"
#include "DNA_space_types.h"
#include "DNA_texture_types.h"
#include "DNA_world_types.h"
 
#include "BKE_action.h"
#include "BKE_anim_data.h"
#include "BKE_animsys.h"
#include "BKE_context.h"
#include "BKE_fcurve.h"
#include "BKE_global.h"
#include "BKE_lib_id.h"
#include "BKE_lib_query.h"
#include "BKE_main.h"
#include "BKE_material.h"
#include "BKE_nla.h"
#include "BKE_node.h"
#include "BKE_report.h"
#include "BKE_texture.h"
 
#include "DEG_depsgraph.h"
#include "DEG_depsgraph_query.h"
 
#include "RNA_access.h"
 
#include "BLO_read_write.h"
 
#include "nla_private.h"
 
#include "atomic_ops.h"
 
#include "CLG_log.h"
 
static CLG_LogRef LOG = {"bke.anim_sys"};
 
/* *********************************** */
/* KeyingSet API */
 
/* Finding Tools --------------------------- */
 
/* Find the first path that matches the given criteria */
/* TODO: do we want some method to perform partial matches too? */
KS_Path *BKE_keyingset_find_path(KeyingSet *ks,
                                 ID *id,
                                 const char group_name[],
                                 const char rna_path[],
                                 int array_index,
                                 int UNUSED(group_mode))
{
  KS_Path *ksp;
 
  /* sanity checks */
  if (ELEM(NULL, ks, rna_path, id)) {
    return NULL;
  }
 
  /* loop over paths in the current KeyingSet, finding the first one where all settings match
   * (i.e. the first one where none of the checks fail and equal 0)
   */
  for (ksp = ks->paths.first; ksp; ksp = ksp->next) {
    short eq_id = 1, eq_path = 1, eq_index = 1, eq_group = 1;
 
    /* id */
    if (id != ksp->id) {
      eq_id = 0;
    }
 
    /* path */
    if ((ksp->rna_path == NULL) || !STREQ(rna_path, ksp->rna_path)) {
      eq_path = 0;
    }
 
    /* index - need to compare whole-array setting too... */
    if (ksp->array_index != array_index) {
      eq_index = 0;
    }
 
    /* group */
    if (group_name) {
      /* FIXME: these checks need to be coded... for now, it's not too important though */
    }
 
    /* if all aspects are ok, return */
    if (eq_id && eq_path && eq_index && eq_group) {
      return ksp;
    }
  }
 
  /* none found */
  return NULL;
}
 
/* Defining Tools --------------------------- */
 
/* Used to create a new 'custom' KeyingSet for the user,
 * that will be automatically added to the stack */
KeyingSet *BKE_keyingset_add(
    ListBase *list, const char idname[], const char name[], short flag, short keyingflag)
{
  KeyingSet *ks;
 
  /* allocate new KeyingSet */
  ks = MEM_callocN(sizeof(KeyingSet), "KeyingSet");
 
  BLI_strncpy(
      ks->idname, (idname) ? idname : (name) ? name : DATA_("KeyingSet"), sizeof(ks->idname));
  BLI_strncpy(ks->name, (name) ? name : (idname) ? idname : DATA_("Keying Set"), sizeof(ks->name));
 
  ks->flag = flag;
  ks->keyingflag = keyingflag;
  /* NOTE: assume that if one is set one way, the other should be too, so that it'll work */
  ks->keyingoverride = keyingflag;
 
  /* add KeyingSet to list */
  BLI_addtail(list, ks);
 
  /* Make sure KeyingSet has a unique idname */
  BLI_uniquename(
      list, ks, DATA_("KeyingSet"), '.', offsetof(KeyingSet, idname), sizeof(ks->idname));
 
  /* Make sure KeyingSet has a unique label (this helps with identification) */
  BLI_uniquename(list, ks, DATA_("Keying Set"), '.', offsetof(KeyingSet, name), sizeof(ks->name));
 
  /* return new KeyingSet for further editing */
  return ks;
}
 
/* Add a path to a KeyingSet. Nothing is returned for now...
 * Checks are performed to ensure that destination is appropriate for the KeyingSet in question
 */
KS_Path *BKE_keyingset_add_path(KeyingSet *ks,
                                ID *id,
                                const char group_name[],
                                const char rna_path[],
                                int array_index,
                                short flag,
                                short groupmode)
{
  KS_Path *ksp;
 
  /* sanity checks */
  if (ELEM(NULL, ks, rna_path)) {
    CLOG_ERROR(&LOG, "no Keying Set and/or RNA Path to add path with");
    return NULL;
  }
 
  /* ID is required for all types of KeyingSets */
  if (id == NULL) {
    CLOG_ERROR(&LOG, "No ID provided for Keying Set Path");
    return NULL;
  }
 
  /* don't add if there is already a matching KS_Path in the KeyingSet */
  if (BKE_keyingset_find_path(ks, id, group_name, rna_path, array_index, groupmode)) {
    if (G.debug & G_DEBUG) {
      CLOG_ERROR(&LOG, "destination already exists in Keying Set");
    }
    return NULL;
  }
 
  /* allocate a new KeyingSet Path */
  ksp = MEM_callocN(sizeof(KS_Path), "KeyingSet Path");
 
  /* just store absolute info */
  ksp->id = id;
  if (group_name) {
    BLI_strncpy(ksp->group, group_name, sizeof(ksp->group));
  }
  else {
    ksp->group[0] = '\0';
  }
 
  /* store additional info for relative paths (just in case user makes the set relative) */
  if (id) {
    ksp->idtype = GS(id->name);
  }
 
  /* just copy path info */
  /* TODO: should array index be checked too? */
  ksp->rna_path = BLI_strdup(rna_path);
  ksp->array_index = array_index;
 
  /* store flags */
  ksp->flag = flag;
  ksp->groupmode = groupmode;
 
  /* add KeyingSet path to KeyingSet */
  BLI_addtail(&ks->paths, ksp);
 
  /* return this path */
  return ksp;
}
 
/* Free the given Keying Set path */
void BKE_keyingset_free_path(KeyingSet *ks, KS_Path *ksp)
{
  /* sanity check */
  if (ELEM(NULL, ks, ksp)) {
    return;
  }
 
  /* free RNA-path info */
  if (ksp->rna_path) {
    MEM_freeN(ksp->rna_path);
  }
 
  /* free path itself */
  BLI_freelinkN(&ks->paths, ksp);
}
 
/* Copy all KeyingSets in the given list */
void BKE_keyingsets_copy(ListBase *newlist, const ListBase *list)
{
  KeyingSet *ksn;
  KS_Path *kspn;
 
  BLI_duplicatelist(newlist, list);
 
  for (ksn = newlist->first; ksn; ksn = ksn->next) {
    BLI_duplicatelist(&ksn->paths, &ksn->paths);
 
    for (kspn = ksn->paths.first; kspn; kspn = kspn->next) {
      kspn->rna_path = MEM_dupallocN(kspn->rna_path);
    }
  }
}
 
void BKE_keyingsets_foreach_id(LibraryForeachIDData *data, const ListBase *keyingsets)
{
  for (KeyingSet *ksn = keyingsets->first; ksn; ksn = ksn->next) {
    for (KS_Path *kspn = ksn->paths.first; kspn; kspn = kspn->next) {
      BKE_LIB_FOREACHID_PROCESS_ID(data, kspn->id, IDWALK_CB_NOP);
    }
  }
}
 
/* Freeing Tools --------------------------- */
 
/* Free data for KeyingSet but not set itself */
void BKE_keyingset_free(KeyingSet *ks)
{
  KS_Path *ksp, *kspn;
 
  /* sanity check */
  if (ks == NULL) {
    return;
  }
 
  /* free each path as we go to avoid looping twice */
  for (ksp = ks->paths.first; ksp; ksp = kspn) {
    kspn = ksp->next;
    BKE_keyingset_free_path(ks, ksp);
  }
}
 
/* Free all the KeyingSets in the given list */
void BKE_keyingsets_free(ListBase *list)
{
  KeyingSet *ks, *ksn;
 
  /* sanity check */
  if (list == NULL) {
    return;
  }
 
  /* loop over KeyingSets freeing them
   * - BKE_keyingset_free() doesn't free the set itself, but it frees its sub-data
   */
  for (ks = list->first; ks; ks = ksn) {
    ksn = ks->next;
    BKE_keyingset_free(ks);
    BLI_freelinkN(list, ks);
  }
}
 
void BKE_keyingsets_blend_write(BlendWriter *writer, ListBase *list)
{
  LISTBASE_FOREACH (KeyingSet *, ks, list) {
    /* KeyingSet */
    BLO_write_struct(writer, KeyingSet, ks);
 
    /* Paths */
    LISTBASE_FOREACH (KS_Path *, ksp, &ks->paths) {
      /* Path */
      BLO_write_struct(writer, KS_Path, ksp);
 
      if (ksp->rna_path) {
        BLO_write_string(writer, ksp->rna_path);
      }
    }
  }
}
 
void BKE_keyingsets_blend_read_data(BlendDataReader *reader, ListBase *list)
{
  LISTBASE_FOREACH (KeyingSet *, ks, list) {
    /* paths */
    BLO_read_list(reader, &ks->paths);
 
    LISTBASE_FOREACH (KS_Path *, ksp, &ks->paths) {
      /* rna path */
      BLO_read_data_address(reader, &ksp->rna_path);
    }
  }
}
 
void BKE_keyingsets_blend_read_lib(BlendLibReader *reader, ID *id, ListBase *list)
{
  LISTBASE_FOREACH (KeyingSet *, ks, list) {
    LISTBASE_FOREACH (KS_Path *, ksp, &ks->paths) {
      BLO_read_id_address(reader, id->lib, &ksp->id);
    }
  }
}
 
void BKE_keyingsets_blend_read_expand(BlendExpander *expander, ListBase *list)
{
  LISTBASE_FOREACH (KeyingSet *, ks, list) {
    LISTBASE_FOREACH (KS_Path *, ksp, &ks->paths) {
      BLO_expand(expander, ksp->id);
    }
  }
}
 
/* ***************************************** */
/* Evaluation Data-Setting Backend */
 
static bool is_fcurve_evaluatable(FCurve *fcu)
{
  if (fcu->flag & (FCURVE_MUTED | FCURVE_DISABLED)) {
    return false;
  }
  if (fcu->grp != NULL && (fcu->grp->flag & AGRP_MUTED)) {
    return false;
  }
  if (BKE_fcurve_is_empty(fcu)) {
    return false;
  }
  return true;
}
 
bool BKE_animsys_rna_path_resolve(PointerRNA *ptr,
                                  /* typically 'fcu->rna_path', 'fcu->array_index' */
                                  const char *rna_path,
                                  const int array_index,
                                  PathResolvedRNA *r_result)
{
  if (rna_path == NULL) {
    return false;
  }
 
  const char *path = rna_path;
  if (!RNA_path_resolve_property(ptr, path, &r_result->ptr, &r_result->prop)) {
    /* failed to get path */
    /* XXX don't tag as failed yet though, as there are some legit situations (Action Constraint)
     * where some channels will not exist, but shouldn't lock up Action */
    if (G.debug & G_DEBUG) {
      CLOG_WARN(&LOG,
                "Animato: Invalid path. ID = '%s',  '%s[%d]'",
                (ptr->owner_id) ? (ptr->owner_id->name + 2) : "<No ID>",
                path,
                array_index);
    }
    return false;
  }
 
  if (ptr->owner_id != NULL && !RNA_property_animateable(&r_result->ptr, r_result->prop)) {
    return false;
  }
 
  int array_len = RNA_property_array_length(&r_result->ptr, r_result->prop);
  if (array_len && array_index >= array_len) {
    if (G.debug & G_DEBUG) {
      CLOG_WARN(&LOG,
                "Animato: Invalid array index. ID = '%s',  '%s[%d]', array length is %d",
                (ptr->owner_id) ? (ptr->owner_id->name + 2) : "<No ID>",
                path,
                array_index,
                array_len - 1);
    }
    return false;
  }
 
  r_result->prop_index = array_len ? array_index : -1;
  return true;
}
 
/* less than 1.0 evaluates to false, use epsilon to avoid float error */
#define ANIMSYS_FLOAT_AS_BOOL(value) ((value) > ((1.0f - FLT_EPSILON)))
 
bool BKE_animsys_read_from_rna_path(PathResolvedRNA *anim_rna, float *r_value)
{
  PropertyRNA *prop = anim_rna->prop;
  PointerRNA *ptr = &anim_rna->ptr;
  int array_index = anim_rna->prop_index;
  float orig_value;
 
  /* caller must ensure this is animatable */
  BLI_assert(RNA_property_animateable(ptr, prop) || ptr->owner_id == NULL);
 
  switch (RNA_property_type(prop)) {
    case PROP_BOOLEAN: {
      if (array_index != -1) {
        const int orig_value_coerce = RNA_property_boolean_get_index(ptr, prop, array_index);
        orig_value = (float)orig_value_coerce;
      }
      else {
        const int orig_value_coerce = RNA_property_boolean_get(ptr, prop);
        orig_value = (float)orig_value_coerce;
      }
      break;
    }
    case PROP_INT: {
      if (array_index != -1) {
        const int orig_value_coerce = RNA_property_int_get_index(ptr, prop, array_index);
        orig_value = (float)orig_value_coerce;
      }
      else {
        const int orig_value_coerce = RNA_property_int_get(ptr, prop);
        orig_value = (float)orig_value_coerce;
      }
      break;
    }
    case PROP_FLOAT: {
      if (array_index != -1) {
        const float orig_value_coerce = RNA_property_float_get_index(ptr, prop, array_index);
        orig_value = (float)orig_value_coerce;
      }
      else {
        const float orig_value_coerce = RNA_property_float_get(ptr, prop);
        orig_value = (float)orig_value_coerce;
      }
      break;
    }
    case PROP_ENUM: {
      const int orig_value_coerce = RNA_property_enum_get(ptr, prop);
      orig_value = (float)orig_value_coerce;
      break;
    }
    default:
      /* nothing can be done here... so it is unsuccessful? */
      return false;
  }
 
  if (r_value != NULL) {
    *r_value = orig_value;
  }
 
  /* successful */
  return true;
}
 
/* Write the given value to a setting using RNA, and return success */
bool BKE_animsys_write_to_rna_path(PathResolvedRNA *anim_rna, const float value)
{
  PropertyRNA *prop = anim_rna->prop;
  PointerRNA *ptr = &anim_rna->ptr;
  int array_index = anim_rna->prop_index;
 
  /* caller must ensure this is animatable */
  BLI_assert(RNA_property_animateable(ptr, prop) || ptr->owner_id == NULL);
 
  /* Check whether value is new. Otherwise we skip all the updates. */
  float old_value;
  if (!BKE_animsys_read_from_rna_path(anim_rna, &old_value)) {
    return false;
  }
  if (old_value == value) {
    return true;
  }
 
  switch (RNA_property_type(prop)) {
    case PROP_BOOLEAN: {
      const int value_coerce = ANIMSYS_FLOAT_AS_BOOL(value);
      if (array_index != -1) {
        RNA_property_boolean_set_index(ptr, prop, array_index, value_coerce);
      }
      else {
        RNA_property_boolean_set(ptr, prop, value_coerce);
      }
      break;
    }
    case PROP_INT: {
      int value_coerce = (int)value;
      RNA_property_int_clamp(ptr, prop, &value_coerce);
      if (array_index != -1) {
        RNA_property_int_set_index(ptr, prop, array_index, value_coerce);
      }
      else {
        RNA_property_int_set(ptr, prop, value_coerce);
      }
      break;
    }
    case PROP_FLOAT: {
      float value_coerce = value;
      RNA_property_float_clamp(ptr, prop, &value_coerce);
      if (array_index != -1) {
        RNA_property_float_set_index(ptr, prop, array_index, value_coerce);
      }
      else {
        RNA_property_float_set(ptr, prop, value_coerce);
      }
      break;
    }
    case PROP_ENUM: {
      const int value_coerce = (int)value;
      RNA_property_enum_set(ptr, prop, value_coerce);
      break;
    }
    default:
      /* nothing can be done here... so it is unsuccessful? */
      return false;
  }
 
  /* successful */
  return true;
}
 
static bool animsys_construct_orig_pointer_rna(const PointerRNA *ptr, PointerRNA *ptr_orig)
{
  *ptr_orig = *ptr;
  /* NOTE: nlastrip_evaluate_controls() creates PointerRNA with ID of NULL. Technically, this is
   * not a valid pointer, but there are exceptions in various places of this file which handles
   * such pointers.
   * We do special trickery here as well, to quickly go from evaluated to original NlaStrip. */
  if (ptr->owner_id == NULL) {
    if (ptr->type != &RNA_NlaStrip) {
      return false;
    }
    NlaStrip *strip = ((NlaStrip *)ptr_orig->data);
    if (strip->orig_strip == NULL) {
      return false;
    }
    ptr_orig->data = strip->orig_strip;
  }
  else {
    ptr_orig->owner_id = ptr_orig->owner_id->orig_id;
    ptr_orig->data = ptr_orig->owner_id;
  }
  return true;
}
 
static void animsys_write_orig_anim_rna(PointerRNA *ptr,
                                        const char *rna_path,
                                        int array_index,
                                        float value)
{
  PointerRNA ptr_orig;
  if (!animsys_construct_orig_pointer_rna(ptr, &ptr_orig)) {
    return;
  }
  PathResolvedRNA orig_anim_rna;
  /* TODO(sergey): Should be possible to cache resolved path in dependency graph somehow. */
  if (BKE_animsys_rna_path_resolve(&ptr_orig, rna_path, array_index, &orig_anim_rna)) {
    BKE_animsys_write_to_rna_path(&orig_anim_rna, value);
  }
}
 
static void animsys_evaluate_fcurves(PointerRNA *ptr,
                                     ListBase *list,
                                     const AnimationEvalContext *anim_eval_context,
                                     bool flush_to_original)
{
  /* Calculate then execute each curve. */
  LISTBASE_FOREACH (FCurve *, fcu, list) {
 
    if (!is_fcurve_evaluatable(fcu)) {
      continue;
    }
 
    PathResolvedRNA anim_rna;
    if (BKE_animsys_rna_path_resolve(ptr, fcu->rna_path, fcu->array_index, &anim_rna)) {
      const float curval = calculate_fcurve(&anim_rna, fcu, anim_eval_context);
      BKE_animsys_write_to_rna_path(&anim_rna, curval);
      if (flush_to_original) {
        animsys_write_orig_anim_rna(ptr, fcu->rna_path, fcu->array_index, curval);
      }
    }
  }
}
 
/* ***************************************** */
/* Driver Evaluation */
 
AnimationEvalContext BKE_animsys_eval_context_construct(struct Depsgraph *depsgraph,
                                                        float eval_time)
{
  AnimationEvalContext ctx = {
      .depsgraph = depsgraph,
      .eval_time = eval_time,
  };
  return ctx;
}
 
AnimationEvalContext BKE_animsys_eval_context_construct_at(
    const AnimationEvalContext *anim_eval_context, float eval_time)
{
  return BKE_animsys_eval_context_construct(anim_eval_context->depsgraph, eval_time);
}
 
/* Evaluate Drivers */
static void animsys_evaluate_drivers(PointerRNA *ptr,
                                     AnimData *adt,
                                     const AnimationEvalContext *anim_eval_context)
{
  FCurve *fcu;
 
  /* drivers are stored as F-Curves, but we cannot use the standard code, as we need to check if
   * the depsgraph requested that this driver be evaluated...
   */
  for (fcu = adt->drivers.first; fcu; fcu = fcu->next) {
    ChannelDriver *driver = fcu->driver;
    bool ok = false;
 
    /* check if this driver's curve should be skipped */
    if ((fcu->flag & (FCURVE_MUTED | FCURVE_DISABLED)) == 0) {
      /* check if driver itself is tagged for recalculation */
      /* XXX driver recalc flag is not set yet by depsgraph! */
      if ((driver) && !(driver->flag & DRIVER_FLAG_INVALID)) {
        /* evaluate this using values set already in other places
         * NOTE: for 'layering' option later on, we should check if we should remove old value
         * before adding new to only be done when drivers only changed. */
        PathResolvedRNA anim_rna;
        if (BKE_animsys_rna_path_resolve(ptr, fcu->rna_path, fcu->array_index, &anim_rna)) {
          const float curval = calculate_fcurve(&anim_rna, fcu, anim_eval_context);
          ok = BKE_animsys_write_to_rna_path(&anim_rna, curval);
        }
 
        /* set error-flag if evaluation failed */
        if (ok == 0) {
          driver->flag |= DRIVER_FLAG_INVALID;
        }
      }
    }
  }
}
 
/* ***************************************** */
/* Actions Evaluation */
 
/* strictly not necessary for actual "evaluation", but it is a useful safety check
 * to reduce the amount of times that users end up having to "revive" wrongly-assigned
 * actions
 */
static void action_idcode_patch_check(ID *id, bAction *act)
{
  int idcode = 0;
 
  /* just in case */
  if (ELEM(NULL, id, act)) {
    return;
  }
 
  idcode = GS(id->name);
 
  /* the actual checks... hopefully not too much of a performance hit in the long run... */
  if (act->idroot == 0) {
    /* use the current root if not set already
     * (i.e. newly created actions and actions from 2.50-2.57 builds).
     * - this has problems if there are 2 users, and the first one encountered is the invalid one
     *   in which case, the user will need to manually fix this (?)
     */
    act->idroot = idcode;
  }
  else if (act->idroot != idcode) {
    /* only report this error if debug mode is enabled (to save performance everywhere else) */
    if (G.debug & G_DEBUG) {
      printf(
          "AnimSys Safety Check Failed: Action '%s' is not meant to be used from ID-Blocks of "
          "type %d such as '%s'\n",
          act->id.name + 2,
          idcode,
          id->name);
    }
  }
}
 
/* ----------------------------------------- */
 
/* Evaluate Action Group */
void animsys_evaluate_action_group(PointerRNA *ptr,
                                   bAction *act,
                                   bActionGroup *agrp,
                                   const AnimationEvalContext *anim_eval_context)
{
  FCurve *fcu;
 
  /* check if mapper is appropriate for use here (we set to NULL if it's inappropriate) */
  if (ELEM(NULL, act, agrp)) {
    return;
  }
 
  action_idcode_patch_check(ptr->owner_id, act);
 
  /* if group is muted, don't evaluated any of the F-Curve */
  if (agrp->flag & AGRP_MUTED) {
    return;
  }
 
  /* calculate then execute each curve */
  for (fcu = agrp->channels.first; (fcu) && (fcu->grp == agrp); fcu = fcu->next) {
    /* check if this curve should be skipped */
    if ((fcu->flag & (FCURVE_MUTED | FCURVE_DISABLED)) == 0 && !BKE_fcurve_is_empty(fcu)) {
      PathResolvedRNA anim_rna;
      if (BKE_animsys_rna_path_resolve(ptr, fcu->rna_path, fcu->array_index, &anim_rna)) {
        const float curval = calculate_fcurve(&anim_rna, fcu, anim_eval_context);
        BKE_animsys_write_to_rna_path(&anim_rna, curval);
      }
    }
  }
}
 
/* Evaluate Action (F-Curve Bag) */
void animsys_evaluate_action(PointerRNA *ptr,
                             bAction *act,
                             const AnimationEvalContext *anim_eval_context,
                             const bool flush_to_original)
{
  /* check if mapper is appropriate for use here (we set to NULL if it's inappropriate) */
  if (act == NULL) {
    return;
  }
 
  action_idcode_patch_check(ptr->owner_id, act);
 
  /* calculate then execute each curve */
  animsys_evaluate_fcurves(ptr, &act->curves, anim_eval_context, flush_to_original);
}
 
/* ***************************************** */
/* NLA System - Evaluation */
 
/* calculate influence of strip based for given frame based on blendin/out values */
static float nlastrip_get_influence(NlaStrip *strip, float cframe)
{
  /* sanity checks - normalize the blendin/out values? */
  strip->blendin = fabsf(strip->blendin);
  strip->blendout = fabsf(strip->blendout);
 
  /* result depends on where frame is in respect to blendin/out values */
  if (IS_EQF(strip->blendin, 0.0f) == false && (cframe <= (strip->start + strip->blendin))) {
    /* there is some blend-in */
    return fabsf(cframe - strip->start) / (strip->blendin);
  }
  if (IS_EQF(strip->blendout, 0.0f) == false && (cframe >= (strip->end - strip->blendout))) {
    /* there is some blend-out */
    return fabsf(strip->end - cframe) / (strip->blendout);
  }
 
  /* in the middle of the strip, we should be full strength */
  return 1.0f;
}
 
/* evaluate the evaluation time and influence for the strip, storing the results in the strip */
static void nlastrip_evaluate_controls(NlaStrip *strip,
                                       const AnimationEvalContext *anim_eval_context,
                                       const bool flush_to_original)
{
  /* now strip's evaluate F-Curves for these settings (if applicable) */
  if (strip->fcurves.first) {
    PointerRNA strip_ptr;
 
    /* create RNA-pointer needed to set values */
    RNA_pointer_create(NULL, &RNA_NlaStrip, strip, &strip_ptr);
 
    /* execute these settings as per normal */
    animsys_evaluate_fcurves(&strip_ptr, &strip->fcurves, anim_eval_context, flush_to_original);
  }
 
  /* analytically generate values for influence and time (if applicable)
   * - we do this after the F-Curves have been evaluated to override the effects of those
   *   in case the override has been turned off.
   */
  if ((strip->flag & NLASTRIP_FLAG_USR_INFLUENCE) == 0) {
    strip->influence = nlastrip_get_influence(strip, anim_eval_context->eval_time);
  }
 
  /* Bypass evaluation time computation if time mapping is disabled. */
  if ((strip->flag & NLASTRIP_FLAG_NO_TIME_MAP) != 0) {
    strip->strip_time = anim_eval_context->eval_time;
    return;
  }
 
  if ((strip->flag & NLASTRIP_FLAG_USR_TIME) == 0) {
    strip->strip_time = nlastrip_get_frame(
        strip, anim_eval_context->eval_time, NLATIME_CONVERT_EVAL);
  }
 
  /* if user can control the evaluation time (using F-Curves), consider the option which allows
   * this time to be clamped to lie within extents of the action-clip, so that a steady changing
   * rate of progress through several cycles of the clip can be achieved easily.
   */
  /* NOTE: if we add any more of these special cases, we better group them up nicely... */
  if ((strip->flag & NLASTRIP_FLAG_USR_TIME) && (strip->flag & NLASTRIP_FLAG_USR_TIME_CYCLIC)) {
    strip->strip_time = fmod(strip->strip_time - strip->actstart, strip->actend - strip->actstart);
  }
}
 
/* gets the strip active at the current time for a list of strips for evaluation purposes */
NlaEvalStrip *nlastrips_ctime_get_strip(ListBase *list,
                                        ListBase *strips,
                                        short index,
                                        const AnimationEvalContext *anim_eval_context,
                                        const bool flush_to_original)
{
  NlaStrip *strip, *estrip = NULL;
  NlaEvalStrip *nes;
  short side = 0;
  float ctime = anim_eval_context->eval_time;
 
  /* loop over strips, checking if they fall within the range */
  for (strip = strips->first; strip; strip = strip->next) {
    /* check if current time occurs within this strip  */
    if (IN_RANGE_INCL(ctime, strip->start, strip->end) ||
        (strip->flag & NLASTRIP_FLAG_NO_TIME_MAP)) {
      /* this strip is active, so try to use it */
      estrip = strip;
      side = NES_TIME_WITHIN;
      break;
    }
 
    /* if time occurred before current strip... */
    if (ctime < strip->start) {
      if (strip == strips->first) {
        /* before first strip - only try to use it if it extends backwards in time too */
        if (strip->extendmode == NLASTRIP_EXTEND_HOLD) {
          estrip = strip;
        }
 
        /* side is 'before' regardless of whether there's a useful strip */
        side = NES_TIME_BEFORE;
      }
      else {
        /* before next strip - previous strip has ended, but next hasn't begun,
         * so blending mode depends on whether strip is being held or not...
         * - only occurs when no transition strip added, otherwise the transition would have
         *   been picked up above...
         */
        strip = strip->prev;
 
        if (strip->extendmode != NLASTRIP_EXTEND_NOTHING) {
          estrip = strip;
        }
        side = NES_TIME_AFTER;
      }
      break;
    }
 
    /* if time occurred after current strip... */
    if (ctime > strip->end) {
      /* only if this is the last strip should we do anything, and only if that is being held */
      if (strip == strips->last) {
        if (strip->extendmode != NLASTRIP_EXTEND_NOTHING) {
          estrip = strip;
        }
 
        side = NES_TIME_AFTER;
        break;
      }
 
      /* otherwise, skip... as the 'before' case will catch it more elegantly! */
    }
  }
 
  /* check if a valid strip was found
   * - must not be muted (i.e. will have contribution
   */
  if ((estrip == NULL) || (estrip->flag & NLASTRIP_FLAG_MUTED)) {
    return NULL;
  }
 
  /* if ctime was not within the boundaries of the strip, clamp! */
  switch (side) {
    case NES_TIME_BEFORE: /* extend first frame only */
      ctime = estrip->start;
      break;
    case NES_TIME_AFTER: /* extend last frame only */
      ctime = estrip->end;
      break;
  }
 
  /* evaluate strip's evaluation controls
   * - skip if no influence (i.e. same effect as muting the strip)
   * - negative influence is not supported yet... how would that be defined?
   */
  /* TODO: this sounds a bit hacky having a few isolated F-Curves
   * stuck on some data it operates on... */
  AnimationEvalContext clamped_eval_context = BKE_animsys_eval_context_construct_at(
      anim_eval_context, ctime);
  nlastrip_evaluate_controls(estrip, &clamped_eval_context, flush_to_original);
  if (estrip->influence <= 0.0f) {
    return NULL;
  }
 
  /* check if strip has valid data to evaluate,
   * and/or perform any additional type-specific actions
   */
  switch (estrip->type) {
    case NLASTRIP_TYPE_CLIP:
      /* clip must have some action to evaluate */
      if (estrip->act == NULL) {
        return NULL;
      }
      break;
    case NLASTRIP_TYPE_TRANSITION:
      /* there must be strips to transition from and to (i.e. prev and next required) */
      if (ELEM(NULL, estrip->prev, estrip->next)) {
        return NULL;
      }
 
      /* evaluate controls for the relevant extents of the bordering strips... */
      AnimationEvalContext start_eval_context = BKE_animsys_eval_context_construct_at(
          anim_eval_context, estrip->start);
      AnimationEvalContext end_eval_context = BKE_animsys_eval_context_construct_at(
          anim_eval_context, estrip->end);
      nlastrip_evaluate_controls(estrip->prev, &start_eval_context, flush_to_original);
      nlastrip_evaluate_controls(estrip->next, &end_eval_context, flush_to_original);
      break;
  }
 
  /* add to list of strips we need to evaluate */
  nes = MEM_callocN(sizeof(NlaEvalStrip), "NlaEvalStrip");
 
  nes->strip = estrip;
  nes->strip_mode = side;
  nes->track_index = index;
  nes->strip_time = estrip->strip_time;
 
  if (list) {
    BLI_addtail(list, nes);
  }
 
  return nes;
}
 
static NlaEvalStrip *nlastrips_ctime_get_strip_single(
    ListBase *dst_list,
    NlaStrip *single_strip,
    const AnimationEvalContext *anim_eval_context,
    const bool flush_to_original)
{
  ListBase single_tracks_list;
  single_tracks_list.first = single_tracks_list.last = single_strip;
 
  return nlastrips_ctime_get_strip(
      dst_list, &single_tracks_list, -1, anim_eval_context, flush_to_original);
}
 
/* ---------------------- */
 
/* Initialize a valid mask, allocating memory if necessary. */
static void nlavalidmask_init(NlaValidMask *mask, int bits)
{
  if (BLI_BITMAP_SIZE(bits) > sizeof(mask->buffer)) {
    mask->ptr = BLI_BITMAP_NEW(bits, "NlaValidMask");
  }
  else {
    mask->ptr = mask->buffer;
  }
}
 
/* Free allocated memory for the mask. */
static void nlavalidmask_free(NlaValidMask *mask)
{
  if (mask->ptr != mask->buffer) {
    MEM_freeN(mask->ptr);
  }
}
 
/* ---------------------- */
 
/* Hashing functions for NlaEvalChannelKey. */
static uint nlaevalchan_keyhash(const void *ptr)
{
  const NlaEvalChannelKey *key = ptr;
  uint hash = BLI_ghashutil_ptrhash(key->ptr.data);
  return hash ^ BLI_ghashutil_ptrhash(key->prop);
}
 
static bool nlaevalchan_keycmp(const void *a, const void *b)
{
  const NlaEvalChannelKey *A = a;
  const NlaEvalChannelKey *B = b;
 
  return ((A->ptr.data != B->ptr.data) || (A->prop != B->prop));
}
 
/* ---------------------- */
 
/* Allocate a new blending value snapshot for the channel. */
static NlaEvalChannelSnapshot *nlaevalchan_snapshot_new(NlaEvalChannel *nec)
{
  int length = nec->base_snapshot.length;
 
  size_t byte_size = sizeof(NlaEvalChannelSnapshot) + sizeof(float) * length;
  NlaEvalChannelSnapshot *nec_snapshot = MEM_callocN(byte_size, "NlaEvalChannelSnapshot");
 
  nec_snapshot->channel = nec;
  nec_snapshot->length = length;
  nlavalidmask_init(&nec_snapshot->blend_domain, length);
 
  return nec_snapshot;
}
 
/* Free a channel's blending value snapshot. */
static void nlaevalchan_snapshot_free(NlaEvalChannelSnapshot *nec_snapshot)
{
  BLI_assert(!nec_snapshot->is_base);
 
  nlavalidmask_free(&nec_snapshot->blend_domain);
  MEM_freeN(nec_snapshot);
}
 
/* Copy all data in the snapshot. */
static void nlaevalchan_snapshot_copy(NlaEvalChannelSnapshot *dst,
                                      const NlaEvalChannelSnapshot *src)
{
  BLI_assert(dst->channel == src->channel);
 
  memcpy(dst->values, src->values, sizeof(float) * dst->length);
}
 
/* ---------------------- */
 
/* Initialize a blending state snapshot structure. */
static void nlaeval_snapshot_init(NlaEvalSnapshot *snapshot,
                                  NlaEvalData *nlaeval,
                                  NlaEvalSnapshot *base)
{
  snapshot->base = base;
  snapshot->size = MAX2(16, nlaeval->num_channels);
  snapshot->channels = MEM_callocN(sizeof(*snapshot->channels) * snapshot->size,
                                   "NlaEvalSnapshot::channels");
}
 
/* Retrieve the individual channel snapshot. */
static NlaEvalChannelSnapshot *nlaeval_snapshot_get(NlaEvalSnapshot *snapshot, int index)
{
  return (index < snapshot->size) ? snapshot->channels[index] : NULL;
}
 
/* Ensure at least this number of slots exists. */
static void nlaeval_snapshot_ensure_size(NlaEvalSnapshot *snapshot, int size)
{
  if (size > snapshot->size) {
    snapshot->size *= 2;
    CLAMP_MIN(snapshot->size, size);
    CLAMP_MIN(snapshot->size, 16);
 
    size_t byte_size = sizeof(*snapshot->channels) * snapshot->size;
    snapshot->channels = MEM_recallocN_id(
        snapshot->channels, byte_size, "NlaEvalSnapshot::channels");
  }
}
 
/* Retrieve the address of a slot in the blending state snapshot for this channel (may realloc). */
static NlaEvalChannelSnapshot **nlaeval_snapshot_ensure_slot(NlaEvalSnapshot *snapshot,
                                                             NlaEvalChannel *nec)
{
  nlaeval_snapshot_ensure_size(snapshot, nec->owner->num_channels);
  return &snapshot->channels[nec->index];
}
 
/* Retrieve the blending snapshot for the specified channel, with fallback to base. */
static NlaEvalChannelSnapshot *nlaeval_snapshot_find_channel(NlaEvalSnapshot *snapshot,
                                                             NlaEvalChannel *nec)
{
  while (snapshot != NULL) {
    NlaEvalChannelSnapshot *nec_snapshot = nlaeval_snapshot_get(snapshot, nec->index);
    if (nec_snapshot != NULL) {
      return nec_snapshot;
    }
    snapshot = snapshot->base;
  }
 
  return &nec->base_snapshot;
}
 
/* Retrieve or create the channel value snapshot, copying from the other snapshot
 * (or default values) */
static NlaEvalChannelSnapshot *nlaeval_snapshot_ensure_channel(NlaEvalSnapshot *snapshot,
                                                               NlaEvalChannel *nec)
{
  NlaEvalChannelSnapshot **slot = nlaeval_snapshot_ensure_slot(snapshot, nec);
 
  if (*slot == NULL) {
    NlaEvalChannelSnapshot *base_snapshot, *nec_snapshot;
 
    nec_snapshot = nlaevalchan_snapshot_new(nec);
    base_snapshot = nlaeval_snapshot_find_channel(snapshot->base, nec);
 
    nlaevalchan_snapshot_copy(nec_snapshot, base_snapshot);
 
    *slot = nec_snapshot;
  }
 
  return *slot;
}
 
/* Free all memory owned by this blending snapshot structure. */
static void nlaeval_snapshot_free_data(NlaEvalSnapshot *snapshot)
{
  if (snapshot->channels != NULL) {
    for (int i = 0; i < snapshot->size; i++) {
      NlaEvalChannelSnapshot *nec_snapshot = snapshot->channels[i];
      if (nec_snapshot != NULL) {
        nlaevalchan_snapshot_free(nec_snapshot);
      }
    }
 
    MEM_freeN(snapshot->channels);
  }
 
  snapshot->base = NULL;
  snapshot->size = 0;
  snapshot->channels = NULL;
}
 
/* ---------------------- */
 
/* Free memory owned by this evaluation channel. */
static void nlaevalchan_free_data(NlaEvalChannel *nec)
{
  nlavalidmask_free(&nec->domain);
}
 
/* Initialize a full NLA evaluation state structure. */
static void nlaeval_init(NlaEvalData *nlaeval)
{
  memset(nlaeval, 0, sizeof(*nlaeval));
 
  nlaeval->path_hash = BLI_ghash_str_new("NlaEvalData::path_hash");
  nlaeval->key_hash = BLI_ghash_new(
      nlaevalchan_keyhash, nlaevalchan_keycmp, "NlaEvalData::key_hash");
}
 
static void nlaeval_free(NlaEvalData *nlaeval)
{
  /* Delete base snapshot - its channels are part of NlaEvalChannel and shouldn't be freed. */
  MEM_SAFE_FREE(nlaeval->base_snapshot.channels);
 
  /* Delete result snapshot. */
  nlaeval_snapshot_free_data(&nlaeval->eval_snapshot);
 
  /* Delete channels. */
  LISTBASE_FOREACH (NlaEvalChannel *, nec, &nlaeval->channels) {
    nlaevalchan_free_data(nec);
  }
 
  BLI_freelistN(&nlaeval->channels);
  BLI_ghash_free(nlaeval->path_hash, NULL, NULL);
  BLI_ghash_free(nlaeval->key_hash, NULL, NULL);
}
 
/* ---------------------- */
 
static int nlaevalchan_validate_index(const NlaEvalChannel *nec, int index)
{
  if (nec->is_array) {
    if (index >= 0 && index < nec->base_snapshot.length) {
      return index;
    }
 
    return -1;
  }
  return 0;
}
 
static bool nlaevalchan_validate_index_ex(const NlaEvalChannel *nec, const int array_index)
{
  const int index = nlaevalchan_validate_index(nec, array_index);
 
  if (index < 0) {
    if (G.debug & G_DEBUG) {
      ID *id = nec->key.ptr.owner_id;
      CLOG_WARN(&LOG,
                "Animation: Invalid array index. ID = '%s',  '%s[%d]', array length is %d",
                id ? (id->name + 2) : "<No ID>",
                nec->rna_path,
                array_index,
                nec->base_snapshot.length);
    }
 
    return false;
  }
  return true;
}
 
/* Initialize default values for NlaEvalChannel from the property data. */
static void nlaevalchan_get_default_values(NlaEvalChannel *nec, float *r_values)
{
  PointerRNA *ptr = &nec->key.ptr;
  PropertyRNA *prop = nec->key.prop;
  int length = nec->base_snapshot.length;
 
  /* Use unit quaternion for quaternion properties. */
  if (nec->mix_mode == NEC_MIX_QUATERNION) {
    unit_qt(r_values);
    return;
  }
  /* Use all zero for Axis-Angle properties. */
  if (nec->mix_mode == NEC_MIX_AXIS_ANGLE) {
    zero_v4(r_values);
    return;
  }
 
  /* NOTE: while this doesn't work for all RNA properties as default values aren't in fact
   * set properly for most of them, at least the common ones (which also happen to get used
   * in NLA strips a lot, e.g. scale) are set correctly.
   */
  if (RNA_property_array_check(prop)) {
    BLI_assert(length == RNA_property_array_length(ptr, prop));
    bool *tmp_bool;
    int *tmp_int;
 
    switch (RNA_property_type(prop)) {
      case PROP_BOOLEAN:
        tmp_bool = MEM_malloc_arrayN(sizeof(*tmp_bool), length, __func__);
        RNA_property_boolean_get_default_array(ptr, prop, tmp_bool);
        for (int i = 0; i < length; i++) {
          r_values[i] = (float)tmp_bool[i];
        }
        MEM_freeN(tmp_bool);
        break;
      case PROP_INT:
        tmp_int = MEM_malloc_arrayN(sizeof(*tmp_int), length, __func__);
        RNA_property_int_get_default_array(ptr, prop, tmp_int);
        for (int i = 0; i < length; i++) {
          r_values[i] = (float)tmp_int[i];
        }
        MEM_freeN(tmp_int);
        break;
      case PROP_FLOAT:
        RNA_property_float_get_default_array(ptr, prop, r_values);
        break;
      default:
        memset(r_values, 0, sizeof(float) * length);
    }
  }
  else {
    BLI_assert(length == 1);
 
    switch (RNA_property_type(prop)) {
      case PROP_BOOLEAN:
        *r_values = (float)RNA_property_boolean_get_default(ptr, prop);
        break;
      case PROP_INT:
        *r_values = (float)RNA_property_int_get_default(ptr, prop);
        break;
      case PROP_FLOAT:
        *r_values = RNA_property_float_get_default(ptr, prop);
        break;
      case PROP_ENUM:
        *r_values = (float)RNA_property_enum_get_default(ptr, prop);
        break;
      default:
        *r_values = 0.0f;
    }
  }
 
  /* Ensure multiplicative properties aren't reset to 0. */
  if (nec->mix_mode == NEC_MIX_MULTIPLY) {
    for (int i = 0; i < length; i++) {
      if (r_values[i] == 0.0f) {
        r_values[i] = 1.0f;
      }
    }
  }
}
 
static char nlaevalchan_detect_mix_mode(NlaEvalChannelKey *key, int length)
{
  PropertySubType subtype = RNA_property_subtype(key->prop);
 
  if (subtype == PROP_QUATERNION && length == 4) {
    return NEC_MIX_QUATERNION;
  }
  if (subtype == PROP_AXISANGLE && length == 4) {
    return NEC_MIX_AXIS_ANGLE;
  }
  if (RNA_property_flag(key->prop) & PROP_PROPORTIONAL) {
    return NEC_MIX_MULTIPLY;
  }
  return NEC_MIX_ADD;
}
 
/* Verify that an appropriate NlaEvalChannel for this property exists. */
static NlaEvalChannel *nlaevalchan_verify_key(NlaEvalData *nlaeval,
                                              const char *path,
                                              NlaEvalChannelKey *key)
{
  /* Look it up in the key hash. */
  NlaEvalChannel **p_key_nec;
  NlaEvalChannelKey **p_key;
  bool found_key = BLI_ghash_ensure_p_ex(
      nlaeval->key_hash, key, (void ***)&p_key, (void ***)&p_key_nec);
 
  if (found_key) {
    return *p_key_nec;
  }
 
  /* Create the channel. */
  bool is_array = RNA_property_array_check(key->prop);
  int length = is_array ? RNA_property_array_length(&key->ptr, key->prop) : 1;
 
  NlaEvalChannel *nec = MEM_callocN(sizeof(NlaEvalChannel) + sizeof(float) * length,
                                    "NlaEvalChannel");
 
  /* Initialize the channel. */
  nec->rna_path = path;
  nec->key = *key;
 
  nec->owner = nlaeval;
  nec->index = nlaeval->num_channels++;
  nec->is_array = is_array;
 
  nec->mix_mode = nlaevalchan_detect_mix_mode(key, length);
 
  nlavalidmask_init(&nec->domain, length);
 
  nec->base_snapshot.channel = nec;
  nec->base_snapshot.length = length;
  nec->base_snapshot.is_base = true;
 
  nlaevalchan_get_default_values(nec, nec->base_snapshot.values);
 
  /* Store channel in data structures. */
  BLI_addtail(&nlaeval->channels, nec);
 
  *nlaeval_snapshot_ensure_slot(&nlaeval->base_snapshot, nec) = &nec->base_snapshot;
 
  *p_key_nec = nec;
  *p_key = &nec->key;
 
  return nec;
}
 
/* Verify that an appropriate NlaEvalChannel for this path exists. */
static NlaEvalChannel *nlaevalchan_verify(PointerRNA *ptr, NlaEvalData *nlaeval, const char *path)
{
  if (path == NULL) {
    return NULL;
  }
 
  /* Lookup the path in the path based hash. */
  NlaEvalChannel **p_path_nec;
  bool found_path = BLI_ghash_ensure_p(nlaeval->path_hash, (void *)path, (void ***)&p_path_nec);
 
  if (found_path) {
    return *p_path_nec;
  }
 
  /* Cache NULL result for now. */
  *p_path_nec = NULL;
 
  /* Resolve the property and look it up in the key hash. */
  NlaEvalChannelKey key;
 
  if (!RNA_path_resolve_property(ptr, path, &key.ptr, &key.prop)) {
    /* Report failure to resolve the path. */
    if (G.debug & G_DEBUG) {
      CLOG_WARN(&LOG,
                "Animato: Invalid path. ID = '%s',  '%s'",
                (ptr->owner_id) ? (ptr->owner_id->name + 2) : "<No ID>",
                path);
    }
 
    return NULL;
  }
 
  /* Check that the property can be animated. */
  if (ptr->owner_id != NULL && !RNA_property_animateable(&key.ptr, key.prop)) {
    return NULL;
  }
 
  NlaEvalChannel *nec = nlaevalchan_verify_key(nlaeval, path, &key);
 
  if (nec->rna_path == NULL) {
    nec->rna_path = path;
  }
 
  return *p_path_nec = nec;
}
 
/* ---------------------- */
 
/* Blend the lower nla stack value and upper strip value of a channel according to mode and
 * influence. */
static float nla_blend_value(const int blendmode,
                             const float lower_value,
                             const float strip_value,
                             const float influence)
{
  /* Optimization: no need to try applying if there is no influence. */
  if (IS_EQF(influence, 0.0f)) {
    return lower_value;
  }
 
  /* Perform blending. */
  switch (blendmode) {
    case NLASTRIP_MODE_ADD:
      /* Simply add the scaled value on to the stack. */
      return lower_value + (strip_value * influence);
 
    case NLASTRIP_MODE_SUBTRACT:
      /* Simply subtract the scaled value from the stack. */
      return lower_value - (strip_value * influence);
 
    case NLASTRIP_MODE_MULTIPLY:
      /* Multiply the scaled value with the stack. */
      return influence * (lower_value * strip_value) + (1 - influence) * lower_value;
 
    case NLASTRIP_MODE_COMBINE:
      BLI_assert(!"combine mode");
      ATTR_FALLTHROUGH;
 
    default:
      /* TODO: Do we really want to blend by default? it seems more uses might prefer add... */
      /* Do linear interpolation. The influence of the accumulated data (elsewhere, that is called
       * dstweight) is 1 - influence, since the strip's influence is srcweight.
       */
      return lower_value * (1.0f - influence) + (strip_value * influence);
  }
}
 
/* Blend the lower nla stack value and upper strip value of a channel according to mode and
 * influence. */
static float nla_combine_value(const int mix_mode,
                               float base_value,
                               const float lower_value,
                               const float strip_value,
                               const float influence)
{
  /* Optimization: No need to try applying if there is no influence. */
  if (IS_EQF(influence, 0.0f)) {
    return lower_value;
  }
 
  /* Perform blending */
  switch (mix_mode) {
    case NEC_MIX_ADD:
    case NEC_MIX_AXIS_ANGLE:
      return lower_value + (strip_value - base_value) * influence;
 
    case NEC_MIX_MULTIPLY:
      if (IS_EQF(base_value, 0.0f)) {
        base_value = 1.0f;
      }
      return lower_value * powf(strip_value / base_value, influence);
 
    default:
      BLI_assert(!"invalid mix mode");
      return lower_value;
  }
}
 
static bool nla_blend_get_inverted_strip_value(const int blendmode,
                                               const float lower_value,
                                               const float blended_value,
                                               const float influence,
                                               float *r_strip_value)
{
  if (IS_EQF(influence, 0.0f)) {
    return false;
  }
 
  switch (blendmode) {
    case NLASTRIP_MODE_ADD:
      *r_strip_value = (blended_value - lower_value) / influence;
      return true;
 
    case NLASTRIP_MODE_SUBTRACT:
      *r_strip_value = (lower_value - blended_value) / influence;
      return true;
 
    case NLASTRIP_MODE_MULTIPLY:
      if (IS_EQF(lower_value, 0.0f)) {
        /* Resolve 0/0 to 1. */
        if (IS_EQF(blended_value, 0.0f)) {
          *r_strip_value = 1.0f;
          return true;
        }
        /* Division by zero. */
        return false;
      }
 
      *r_strip_value = ((blended_value - lower_value) / (influence * lower_value)) + 1.0f;
      return true;
 
    case NLASTRIP_MODE_COMBINE:
      BLI_assert(!"combine mode");
      ATTR_FALLTHROUGH;
 
    default:
 
      *r_strip_value = (blended_value - lower_value * (1.0f - influence)) / influence;
      return true;
  }
}
 
static bool nla_combine_get_inverted_strip_value(const int mix_mode,
                                                 float base_value,
                                                 const float lower_value,
                                                 const float blended_value,
                                                 const float influence,
                                                 float *r_strip_value)
{
  /* No solution if strip had no influence. */
  if (IS_EQF(influence, 0.0f)) {
    return false;
  }
 
  switch (mix_mode) {
    case NEC_MIX_ADD:
    case NEC_MIX_AXIS_ANGLE:
      *r_strip_value = base_value + (blended_value - lower_value) / influence;
      return true;
 
    case NEC_MIX_MULTIPLY:
      if (IS_EQF(base_value, 0.0f)) {
        base_value = 1.0f;
      }
      /* Division by zero. */
      if (IS_EQF(lower_value, 0.0f)) {
        /* Resolve 0/0 to 1. */
        if (IS_EQF(blended_value, 0.0f)) {
          *r_strip_value = base_value;
          return true;
        }
        /* Division by zero. */
        return false;
      }
 
      *r_strip_value = base_value * powf(blended_value / lower_value, 1.0f / influence);
      return true;
 
    default:
      BLI_assert(!"invalid mix mode");
      return false;
  }
}
 
static void nla_combine_quaternion(const float lower_values[4],
                                   const float strip_values[4],
                                   const float influence,
                                   float r_blended_value[4])
{
  float tmp_lower[4], tmp_strip_values[4];
 
  normalize_qt_qt(tmp_lower, lower_values);
  normalize_qt_qt(tmp_strip_values, strip_values);
 
  pow_qt_fl_normalized(tmp_strip_values, influence);
  mul_qt_qtqt(r_blended_value, tmp_lower, tmp_strip_values);
}
 
static bool nla_combine_quaternion_get_inverted_strip_values(const float lower_values[4],
                                                             const float blended_values[4],
                                                             const float influence,
                                                             float r_strip_values[4])
{
  /* blended_value = lower_values @ r_strip_values^infl
   * inv(lower_values) @ blended_value = r_strip_values^infl
   * (inv(lower_values) @ blended_value) ^ (1/inf) = r_strip_values
   *
   * Returns: r_strip_values = (inv(lower_values) @ blended_value) ^ (1/inf) */
  if (IS_EQF(influence, 0.0f)) {
    return false;
  }
  float tmp_lower[4], tmp_blended[4];
 
  normalize_qt_qt(tmp_lower, lower_values);
  normalize_qt_qt(tmp_blended, blended_values);
  invert_qt_normalized(tmp_lower);
 
  mul_qt_qtqt(r_strip_values, tmp_lower, tmp_blended);
  pow_qt_fl_normalized(r_strip_values, 1.0f / influence);
 
  return true;
}
 
/* ---------------------- */
/* F-Modifier stack joining/separation utilities -
 * should we generalize these for BLI_listbase.h interface? */
 
/* Temporarily join two lists of modifiers together, storing the result in a third list */
static void nlaeval_fmodifiers_join_stacks(ListBase *result, ListBase *list1, ListBase *list2)
{
  FModifier *fcm1, *fcm2;
 
  /* if list1 is invalid...  */
  if (ELEM(NULL, list1, list1->first)) {
    if (list2 && list2->first) {
      result->first = list2->first;
      result->last = list2->last;
    }
  }
  /* if list 2 is invalid... */
  else if (ELEM(NULL, list2, list2->first)) {
    result->first = list1->first;
    result->last = list1->last;
  }
  else {
    /* list1 should be added first, and list2 second,
     * with the endpoints of these being the endpoints for result
     * - the original lists must be left unchanged though, as we need that fact for restoring.
     */
    result->first = list1->first;
    result->last = list2->last;
 
    fcm1 = list1->last;
    fcm2 = list2->first;
 
    fcm1->next = fcm2;
    fcm2->prev = fcm1;
  }
}
 
/* Split two temporary lists of modifiers */
static void nlaeval_fmodifiers_split_stacks(ListBase *list1, ListBase *list2)
{
  FModifier *fcm1, *fcm2;
 
  /* if list1/2 is invalid... just skip */
  if (ELEM(NULL, list1, list2)) {
    return;
  }
  if (ELEM(NULL, list1->first, list2->first)) {
    return;
  }
 
  /* get endpoints */
  fcm1 = list1->last;
  fcm2 = list2->first;
 
  /* clear their links */
  fcm1->next = NULL;
  fcm2->prev = NULL;
}
 
/* ---------------------- */
 
static void nlasnapshot_from_action(PointerRNA *ptr,
                                    NlaEvalData *channels,
                                    ListBase *modifiers,
                                    bAction *action,
                                    const float evaltime,
                                    NlaEvalSnapshot *r_snapshot)
{
  FCurve *fcu;
 
  action_idcode_patch_check(ptr->owner_id, action);
 
  /* Evaluate modifiers which modify time to evaluate the base curves at. */
  FModifiersStackStorage storage;
  storage.modifier_count = BLI_listbase_count(modifiers);
  storage.size_per_modifier = evaluate_fmodifiers_storage_size_per_modifier(modifiers);
  storage.buffer = alloca(storage.modifier_count * storage.size_per_modifier);
 
  const float modified_evaltime = evaluate_time_fmodifiers(
      &storage, modifiers, NULL, 0.0f, evaltime);
 
  for (fcu = action->curves.first; fcu; fcu = fcu->next) {
    if (!is_fcurve_evaluatable(fcu)) {
      continue;
    }
 
    NlaEvalChannel *nec = nlaevalchan_verify(ptr, channels, fcu->rna_path);
 
    /* Invalid path or property cannot be animated. */
    if (nec == NULL) {
      continue;
    }
 
    if (!nlaevalchan_validate_index_ex(nec, fcu->array_index)) {
      continue;
    }
 
    NlaEvalChannelSnapshot *necs = nlaeval_snapshot_ensure_channel(r_snapshot, nec);
 
    float value = evaluate_fcurve(fcu, modified_evaltime);
    evaluate_value_fmodifiers(&storage, modifiers, fcu, &value, evaltime);
    necs->values[fcu->array_index] = value;
 
    if (nec->mix_mode == NEC_MIX_QUATERNION) {
      BLI_bitmap_set_all(necs->blend_domain.ptr, true, 4);
    }
    else {
      BLI_BITMAP_ENABLE(necs->blend_domain.ptr, fcu->array_index);
    }
  }
}
 
/* evaluate action-clip strip */
static void nlastrip_evaluate_actionclip(PointerRNA *ptr,
                                         NlaEvalData *channels,
                                         ListBase *modifiers,
                                         NlaEvalStrip *nes,
                                         NlaEvalSnapshot *snapshot)
{
 
  NlaStrip *strip = nes->strip;
 
  /* sanity checks for action */
  if (strip == NULL) {
    return;
  }
 
  if (strip->act == NULL) {
    CLOG_ERROR(&LOG, "NLA-Strip Eval Error: Strip '%s' has no Action", strip->name);
    return;
  }
 
  ListBase tmp_modifiers = {NULL, NULL};
 
  /* join this strip's modifiers to the parent's modifiers (own modifiers first) */
  nlaeval_fmodifiers_join_stacks(&tmp_modifiers, &strip->modifiers, modifiers);
 
  NlaEvalSnapshot strip_snapshot;
  nlaeval_snapshot_init(&strip_snapshot, channels, NULL);
 
  nlasnapshot_from_action(
      ptr, channels, &tmp_modifiers, strip->act, strip->strip_time, &strip_snapshot);
  nlasnapshot_blend(
      channels, snapshot, &strip_snapshot, strip->blendmode, strip->influence, snapshot);
 
  nlaeval_snapshot_free_data(&strip_snapshot);
 
  /* unlink this strip's modifiers from the parent's modifiers again */
  nlaeval_fmodifiers_split_stacks(&strip->modifiers, modifiers);
}
 
/* evaluate transition strip */
static void nlastrip_evaluate_transition(PointerRNA *ptr,
                                         NlaEvalData *channels,
                                         ListBase *modifiers,
                                         NlaEvalStrip *nes,
                                         NlaEvalSnapshot *snapshot,
                                         const AnimationEvalContext *anim_eval_context,
                                         const bool flush_to_original)
{
  ListBase tmp_modifiers = {NULL, NULL};
  NlaEvalSnapshot snapshot1, snapshot2;
  NlaEvalStrip tmp_nes;
  NlaStrip *s1, *s2;
 
  /* join this strip's modifiers to the parent's modifiers (own modifiers first) */
  nlaeval_fmodifiers_join_stacks(&tmp_modifiers, &nes->strip->modifiers, modifiers);
 
  /* get the two strips to operate on
   * - we use the endpoints of the strips directly flanking our strip
   *   using these as the endpoints of the transition (destination and source)
   * - these should have already been determined to be valid...
   * - if this strip is being played in reverse, we need to swap these endpoints
   *   otherwise they will be interpolated wrong
   */
  if (nes->strip->flag & NLASTRIP_FLAG_REVERSE) {
    s1 = nes->strip->next;
    s2 = nes->strip->prev;
  }
  else {
    s1 = nes->strip->prev;
    s2 = nes->strip->next;
  }
 
  /* prepare template for 'evaluation strip'
   * - based on the transition strip's evaluation strip data
   * - strip_mode is NES_TIME_TRANSITION_* based on which endpoint
   * - strip_time is the 'normalized' (i.e. in-strip) time for evaluation,
   *   which doubles up as an additional weighting factor for the strip influences
   *   which allows us to appear to be 'interpolating' between the two extremes
   */
  tmp_nes = *nes;
 
  /* evaluate these strips into a temp-buffer (tmp_channels) */
  /* FIXME: modifier evaluation here needs some work... */
  /* first strip */
  tmp_nes.strip_mode = NES_TIME_TRANSITION_START;
  tmp_nes.strip = s1;
  tmp_nes.strip_time = s1->strip_time;
  nlaeval_snapshot_init(&snapshot1, channels, snapshot);
  nlastrip_evaluate(
      ptr, channels, &tmp_modifiers, &tmp_nes, &snapshot1, anim_eval_context, flush_to_original);
 
  /* second strip */
  tmp_nes.strip_mode = NES_TIME_TRANSITION_END;
  tmp_nes.strip = s2;
  tmp_nes.strip_time = s2->strip_time;
  nlaeval_snapshot_init(&snapshot2, channels, snapshot);
  nlastrip_evaluate(
      ptr, channels, &tmp_modifiers, &tmp_nes, &snapshot2, anim_eval_context, flush_to_original);
 
  nlasnapshot_ensure_channels(channels, &snapshot2);
  nlasnapshot_enable_all_blend_domain(&snapshot2);
  nlasnapshot_blend(
      channels, &snapshot1, &snapshot2, NLASTRIP_MODE_REPLACE, nes->strip_time, snapshot);
 
  nlaeval_snapshot_free_data(&snapshot1);
  nlaeval_snapshot_free_data(&snapshot2);
 
  /* unlink this strip's modifiers from the parent's modifiers again */
  nlaeval_fmodifiers_split_stacks(&nes->strip->modifiers, modifiers);
}
 
/* evaluate meta-strip */
static void nlastrip_evaluate_meta(PointerRNA *ptr,
                                   NlaEvalData *channels,
                                   ListBase *modifiers,
                                   NlaEvalStrip *nes,
                                   NlaEvalSnapshot *snapshot,
                                   const AnimationEvalContext *anim_eval_context,
                                   const bool flush_to_original)
{
  ListBase tmp_modifiers = {NULL, NULL};
  NlaStrip *strip = nes->strip;
  NlaEvalStrip *tmp_nes;
  float evaltime;
 
  /* meta-strip was calculated normally to have some time to be evaluated at
   * and here we 'look inside' the meta strip, treating it as a decorated window to
   * its child strips, which get evaluated as if they were some tracks on a strip
   * (but with some extra modifiers to apply).
   *
   * NOTE: keep this in sync with animsys_evaluate_nla()
   */
 
  /* join this strip's modifiers to the parent's modifiers (own modifiers first) */
  nlaeval_fmodifiers_join_stacks(&tmp_modifiers, &strip->modifiers, modifiers);
 
  /* find the child-strip to evaluate */
  evaltime = (nes->strip_time * (strip->end - strip->start)) + strip->start;
  AnimationEvalContext child_context = BKE_animsys_eval_context_construct_at(anim_eval_context,
                                                                             evaltime);
  tmp_nes = nlastrips_ctime_get_strip(NULL, &strip->strips, -1, &child_context, flush_to_original);
 
  /* directly evaluate child strip into accumulation buffer...
   * - there's no need to use a temporary buffer (as it causes issues [T40082])
   */
  if (tmp_nes) {
    nlastrip_evaluate(
        ptr, channels, &tmp_modifiers, tmp_nes, snapshot, &child_context, flush_to_original);
 
    /* free temp eval-strip */
    MEM_freeN(tmp_nes);
  }
 
  /* unlink this strip's modifiers from the parent's modifiers again */
  nlaeval_fmodifiers_split_stacks(&strip->modifiers, modifiers);
}
 
/* evaluates the given evaluation strip */
void nlastrip_evaluate(PointerRNA *ptr,
                       NlaEvalData *channels,
                       ListBase *modifiers,
                       NlaEvalStrip *nes,
                       NlaEvalSnapshot *snapshot,
                       const AnimationEvalContext *anim_eval_context,
                       const bool flush_to_original)
{
  NlaStrip *strip = nes->strip;
 
  /* To prevent potential infinite recursion problems
   * (i.e. transition strip, beside meta strip containing a transition
   * several levels deep inside it),
   * we tag the current strip as being evaluated, and clear this when we leave.
   */
  /* TODO: be careful with this flag, since some edit tools may be running and have
   * set this while animation playback was running. */
  if (strip->flag & NLASTRIP_FLAG_EDIT_TOUCHED) {
    return;
  }
  strip->flag |= NLASTRIP_FLAG_EDIT_TOUCHED;
 
  /* actions to take depend on the type of strip */
  switch (strip->type) {
    case NLASTRIP_TYPE_CLIP: /* action-clip */
      nlastrip_evaluate_actionclip(ptr, channels, modifiers, nes, snapshot);
      break;
    case NLASTRIP_TYPE_TRANSITION: /* transition */
      nlastrip_evaluate_transition(
          ptr, channels, modifiers, nes, snapshot, anim_eval_context, flush_to_original);
      break;
    case NLASTRIP_TYPE_META: /* meta */
      nlastrip_evaluate_meta(
          ptr, channels, modifiers, nes, snapshot, anim_eval_context, flush_to_original);
      break;
 
    default: /* do nothing */
      break;
  }
 
  /* clear temp recursion safe-check */
  strip->flag &= ~NLASTRIP_FLAG_EDIT_TOUCHED;
}
 
/* write the accumulated settings to */
void nladata_flush_channels(PointerRNA *ptr,
                            NlaEvalData *channels,
                            NlaEvalSnapshot *snapshot,
                            const bool flush_to_original)
{
  /* sanity checks */
  if (channels == NULL) {
    return;
  }
 
  /* for each channel with accumulated values, write its value on the property it affects */
  LISTBASE_FOREACH (NlaEvalChannel *, nec, &channels->channels) {
    NlaEvalChannelSnapshot *nec_snapshot = nlaeval_snapshot_find_channel(snapshot, nec);
 
    PathResolvedRNA rna = {nec->key.ptr, nec->key.prop, -1};
 
    for (int i = 0; i < nec_snapshot->length; i++) {
      if (BLI_BITMAP_TEST(nec->domain.ptr, i)) {
        float value = nec_snapshot->values[i];
        if (nec->is_array) {
          rna.prop_index = i;
        }
        BKE_animsys_write_to_rna_path(&rna, value);
        if (flush_to_original) {
          animsys_write_orig_anim_rna(ptr, nec->rna_path, rna.prop_index, value);
        }
      }
    }
  }
}
 
/* ---------------------- */
 
static void nla_eval_domain_action(PointerRNA *ptr,
                                   NlaEvalData *channels,
                                   bAction *act,
                                   GSet *touched_actions)
{
  if (!BLI_gset_add(touched_actions, act)) {
    return;
  }
 
  LISTBASE_FOREACH (FCurve *, fcu, &act->curves) {
    /* check if this curve should be skipped */
    if (!is_fcurve_evaluatable(fcu)) {
      continue;
    }
 
    NlaEvalChannel *nec = nlaevalchan_verify(ptr, channels, fcu->rna_path);
 
    if (nec != NULL) {
      /* For quaternion properties, enable all sub-channels. */
      if (nec->mix_mode == NEC_MIX_QUATERNION) {
        BLI_bitmap_set_all(nec->domain.ptr, true, 4);
        continue;
      }
 
      int idx = nlaevalchan_validate_index(nec, fcu->array_index);
 
      if (idx >= 0) {
        BLI_BITMAP_ENABLE(nec->domain.ptr, idx);
      }
    }
  }
}
 
static void nla_eval_domain_strips(PointerRNA *ptr,
                                   NlaEvalData *channels,
                                   ListBase *strips,
                                   GSet *touched_actions)
{
  LISTBASE_FOREACH (NlaStrip *, strip, strips) {
    /* check strip's action */
    if (strip->act) {
      nla_eval_domain_action(ptr, channels, strip->act, touched_actions);
    }
 
    /* check sub-strips (if metas) */
    nla_eval_domain_strips(ptr, channels, &strip->strips, touched_actions);
  }
}
 
static void animsys_evaluate_nla_domain(PointerRNA *ptr, NlaEvalData *channels, AnimData *adt)
{
  GSet *touched_actions = BLI_gset_ptr_new(__func__);
 
  if (adt->action) {
    nla_eval_domain_action(ptr, channels, adt->action, touched_actions);
  }
 
  /* NLA Data - Animation Data for Strips */
  LISTBASE_FOREACH (NlaTrack *, nlt, &adt->nla_tracks) {
    /* solo and muting are mutually exclusive... */
    if (adt->flag & ADT_NLA_SOLO_TRACK) {
      /* skip if there is a solo track, but this isn't it */
      if ((nlt->flag & NLATRACK_SOLO) == 0) {
        continue;
      }
      /* else - mute doesn't matter */
    }
    else {
      /* no solo tracks - skip track if muted */
      if (nlt->flag & NLATRACK_MUTED) {
        continue;
      }
    }
 
    nla_eval_domain_strips(ptr, channels, &nlt->strips, touched_actions);
  }
 
  BLI_gset_free(touched_actions, NULL);
}
 
/* ---------------------- */
 
static void animsys_create_tweak_strip(const AnimData *adt,
                                       const bool keyframing_to_strip,
                                       NlaStrip *r_tweak_strip)
 
{
  /* Copy active strip so we can modify how it evaluates without affecting user data. */
  memcpy(r_tweak_strip, adt->actstrip, sizeof(NlaStrip));
  r_tweak_strip->next = r_tweak_strip->prev = NULL;
 
  /* If tweaked strip is syncing action length, then evaluate using action length. */
  if (r_tweak_strip->flag & NLASTRIP_FLAG_SYNC_LENGTH) {
    BKE_nlastrip_recalculate_bounds_sync_action(r_tweak_strip);
  }
 
  /* Strips with a user-defined time curve don't get properly remapped for editing
   * at the moment, so mapping them just for display may be confusing. */
  const bool is_inplace_tweak = !(adt->flag & ADT_NLA_EDIT_NOMAP) &&
                                !(adt->actstrip->flag & NLASTRIP_FLAG_USR_TIME);
 
  if (!is_inplace_tweak) {
    /* Use Hold due to no proper remapping yet (the note above). */
    r_tweak_strip->extendmode = NLASTRIP_EXTEND_HOLD;
 
    /* Disable range. */
    r_tweak_strip->flag |= NLASTRIP_FLAG_NO_TIME_MAP;
  }
 
  if (keyframing_to_strip) {
    r_tweak_strip->extendmode = (is_inplace_tweak &&
                                 !(r_tweak_strip->flag & NLASTRIP_FLAG_SYNC_LENGTH)) ?
                                    NLASTRIP_EXTEND_NOTHING :
                                    NLASTRIP_EXTEND_HOLD;
  }
}
 
static void animsys_create_action_track_strip(const AnimData *adt,
                                              const bool keyframing_to_strip,
                                              NlaStrip *r_action_strip)
{
  memset(r_action_strip, 0, sizeof(NlaStrip));
 
  bAction *action = adt->action;
 
  if ((adt->flag & ADT_NLA_EDIT_ON)) {
    action = adt->tmpact;
  }
 
  /* Set settings of dummy NLA strip from AnimData settings. */
  r_action_strip->act = action;
 
  /* Action range is calculated taking F-Modifiers into account
   * (which making new strips doesn't do due to the troublesome nature of that). */
  calc_action_range(r_action_strip->act, &r_action_strip->actstart, &r_action_strip->actend, 1);
  r_action_strip->start = r_action_strip->actstart;
  r_action_strip->end = (IS_EQF(r_action_strip->actstart, r_action_strip->actend)) ?
                            (r_action_strip->actstart + 1.0f) :
                            (r_action_strip->actend);
 
  r_action_strip->blendmode = adt->act_blendmode;
  r_action_strip->extendmode = adt->act_extendmode;
  r_action_strip->influence = adt->act_influence;
 
  /* NOTE: must set this, or else the default setting overrides,
   * and this setting doesn't work. */
  r_action_strip->flag |= NLASTRIP_FLAG_USR_INFLUENCE;
 
  /* Unless extendmode is Nothing (might be useful for flattening NLA evaluation), disable range.
   * Extendmode Nothing and Hold will behave as normal. Hold Forward will behave just like Hold.
   */
  if (r_action_strip->extendmode != NLASTRIP_EXTEND_NOTHING) {
    r_action_strip->flag |= NLASTRIP_FLAG_NO_TIME_MAP;
  }
 
  const bool tweaking = (adt->flag & ADT_NLA_EDIT_ON) != 0;
  const bool soloing = (adt->flag & ADT_NLA_SOLO_TRACK) != 0;
  const bool actionstrip_evaluated = r_action_strip->act && !soloing && !tweaking;
  if (!actionstrip_evaluated) {
    r_action_strip->flag |= NLASTRIP_FLAG_MUTED;
  }
 
  if (keyframing_to_strip) {
    r_action_strip->extendmode = NLASTRIP_EXTEND_HOLD;
  }
}
 
static bool is_nlatrack_evaluatable(const AnimData *adt, const NlaTrack *nlt)
{
  /* Skip disabled tracks unless it contains the tweaked strip. */
  const bool contains_tweak_strip = (adt->flag & ADT_NLA_EDIT_ON) && adt->act_track &&
                                    (nlt->index == adt->act_track->index);
  if ((nlt->flag & NLATRACK_DISABLED) && !contains_tweak_strip) {
    return false;
  }
 
  /* Solo and muting are mutually exclusive. */
  if (adt->flag & ADT_NLA_SOLO_TRACK) {
    /* Skip if there is a solo track, but this isn't it. */
    if ((nlt->flag & NLATRACK_SOLO) == 0) {
      return false;
    }
  }
  else {
    /* Skip track if muted. */
    if (nlt->flag & NLATRACK_MUTED) {
      return false;
    }
  }
 
  return true;
}
 
static bool is_action_track_evaluated_without_nla(const AnimData *adt,
                                                  const bool any_strip_evaluated)
{
  if (adt->action == NULL) {
    return false;
  }
 
  if (any_strip_evaluated) {
    return false;
  }
 
  if ((adt->flag & (ADT_NLA_SOLO_TRACK | ADT_NLA_EDIT_ON)) != 0) {
    return false;
  }
 
  return true;
}
 
static NlaTrack *nlatrack_find_tweaked(const AnimData *adt)
{
  NlaTrack *nlt;
 
  if (adt == NULL) {
    return NULL;
  }
 
  /* Since the track itself gets disabled, we want the first disabled. */
  for (nlt = adt->nla_tracks.first; nlt; nlt = nlt->next) {
    if (nlt->flag & NLATRACK_DISABLED) {
      return nlt;
    }
  }
 
  return NULL;
}
 
static bool animsys_evaluate_nla_for_flush(NlaEvalData *echannels,
                                           PointerRNA *ptr,
                                           const AnimData *adt,
                                           const AnimationEvalContext *anim_eval_context,
                                           const bool flush_to_original)
{
  NlaTrack *nlt;
  short track_index = 0;
  bool has_strips = false;
  ListBase estrips = {NULL, NULL};
  NlaEvalStrip *nes;
 
  NlaStrip tweak_strip;
 
  NlaTrack *tweaked_track = nlatrack_find_tweaked(adt);
 
  /* Get the stack of strips to evaluate at current time (influence calculated here). */
  for (nlt = adt->nla_tracks.first; nlt; nlt = nlt->next, track_index++) {
 
    if (!is_nlatrack_evaluatable(adt, nlt)) {
      continue;
    }
 
    if (nlt->strips.first) {
      has_strips = true;
    }
 
    if (nlt == tweaked_track) {
      animsys_create_tweak_strip(adt, false, &tweak_strip);
      nes = nlastrips_ctime_get_strip_single(
          &estrips, &tweak_strip, anim_eval_context, flush_to_original);
    }
    else {
      nes = nlastrips_ctime_get_strip(
          &estrips, &nlt->strips, track_index, anim_eval_context, flush_to_original);
    }
    if (nes) {
      nes->track = nlt;
    }
  }
 
  if (is_action_track_evaluated_without_nla(adt, has_strips)) {
    BLI_freelistN(&estrips);
    return false;
  }
 
  NlaStrip action_strip = {0};
  animsys_create_action_track_strip(adt, false, &action_strip);
  nlastrips_ctime_get_strip_single(&estrips, &action_strip, anim_eval_context, flush_to_original);
 
  /* Per strip, evaluate and accumulate on top of existing channels. */
  for (nes = estrips.first; nes; nes = nes->next) {
    nlastrip_evaluate(ptr,
                      echannels,
                      NULL,
                      nes,
                      &echannels->eval_snapshot,
                      anim_eval_context,
                      flush_to_original);
  }
 
  /* Free temporary evaluation data that's not used elsewhere. */
  BLI_freelistN(&estrips);
  return true;
}
 
static void animsys_evaluate_nla_for_keyframing(PointerRNA *ptr,
                                                const AnimData *adt,
                                                const AnimationEvalContext *anim_eval_context,
                                                NlaKeyframingContext *r_context)
{
  if (!r_context) {
    return;
  }
 
  /* Early out. If NLA track is soloing and tweaked action isn't it, then don't allow keyframe
   * insertion. */
  if (adt->flag & ADT_NLA_SOLO_TRACK) {
    if (!(adt->act_track && (adt->act_track->flag & NLATRACK_SOLO))) {
      r_context->eval_strip = NULL;
      return;
    }
  }
 
  NlaTrack *nlt;
  short track_index = 0;
  bool has_strips = false;
 
  ListBase lower_estrips = {NULL, NULL};
  NlaEvalStrip *nes;
 
  NlaTrack *tweaked_track = nlatrack_find_tweaked(adt);
 
  /* Get the lower stack of strips to evaluate at current time (influence calculated here). */
  for (nlt = adt->nla_tracks.first; nlt; nlt = nlt->next, track_index++) {
 
    if (!is_nlatrack_evaluatable(adt, nlt)) {
      continue;
    }
 
    /* Tweaked strip effect should not be stored in any snapshot. */
    if (nlt == tweaked_track) {
      break;
    }
 
    if (nlt->strips.first) {
      has_strips = true;
    }
 
    /* Get strip to evaluate for this channel. */
    nes = nlastrips_ctime_get_strip(
        &lower_estrips, &nlt->strips, track_index, anim_eval_context, false);
    if (nes) {
      nes->track = nlt;
    }
  }
 
  if (is_action_track_evaluated_without_nla(adt, has_strips)) {
    BLI_freelistN(&lower_estrips);
    return;
  }
 
  /* Write r_context->eval_strip. */
  if (adt->flag & ADT_NLA_EDIT_ON) {
 
    NlaStrip *tweak_strip = &r_context->strip;
    animsys_create_tweak_strip(adt, true, tweak_strip);
    r_context->eval_strip = nlastrips_ctime_get_strip_single(
        NULL, tweak_strip, anim_eval_context, false);
  }
  else {
 
    NlaStrip *action_strip = &r_context->strip;
    animsys_create_action_track_strip(adt, true, action_strip);
    r_context->eval_strip = nlastrips_ctime_get_strip_single(
        NULL, action_strip, anim_eval_context, false);
  }
 
  /* If NULL, then keyframing will fail. No need to do any more processing. */
  if (!r_context->eval_strip) {
    BLI_freelistN(&lower_estrips);
    return;
  }
 
  /* If tweak strip is full REPLACE, then lower strips not needed. */
  if (r_context->strip.blendmode == NLASTRIP_MODE_REPLACE &&
      IS_EQF(r_context->strip.influence, 1.0f)) {
    BLI_freelistN(&lower_estrips);
    return;
  }
 
  /* For each strip, evaluate then accumulate on top of existing channels. */
  for (nes = lower_estrips.first; nes; nes = nes->next) {
    nlastrip_evaluate(ptr,
                      &r_context->lower_eval_data,
                      NULL,
                      nes,
                      &r_context->lower_eval_data.eval_snapshot,
                      anim_eval_context,
                      false);
  }
 
  /* Free temporary evaluation data that's not used elsewhere. */
  BLI_freelistN(&lower_estrips);
}
 
/* NLA Evaluation function (mostly for use through do_animdata)
 * - All channels that will be affected are not cleared anymore. Instead, we just evaluate into
 *   some temp channels, where values can be accumulated in one go.
 */
static void animsys_calculate_nla(PointerRNA *ptr,
                                  AnimData *adt,
                                  const AnimationEvalContext *anim_eval_context,
                                  const bool flush_to_original)
{
  NlaEvalData echannels;
 
  nlaeval_init(&echannels);
 
  /* evaluate the NLA stack, obtaining a set of values to flush */
  if (animsys_evaluate_nla_for_flush(&echannels, ptr, adt, anim_eval_context, flush_to_original)) {
    /* reset any channels touched by currently inactive actions to default value */
    animsys_evaluate_nla_domain(ptr, &echannels, adt);
 
    /* flush effects of accumulating channels in NLA to the actual data they affect */
    nladata_flush_channels(ptr, &echannels, &echannels.eval_snapshot, flush_to_original);
  }
  else {
    /* special case - evaluate as if there isn't any NLA data */
    /* TODO: this is really just a stop-gap measure... */
    if (G.debug & G_DEBUG) {
      CLOG_WARN(&LOG, "NLA Eval: Stopgap for active action on NLA Stack - no strips case");
    }
 
    animsys_evaluate_action(ptr, adt->action, anim_eval_context, flush_to_original);
  }
 
  /* free temp data */
  nlaeval_free(&echannels);
}
 
/* ---------------------- */
 
void nlasnapshot_enable_all_blend_domain(NlaEvalSnapshot *snapshot)
{
  for (int i = 0; i < snapshot->size; i++) {
    NlaEvalChannelSnapshot *necs = nlaeval_snapshot_get(snapshot, i);
    if (necs == NULL) {
      continue;
    }
 
    BLI_bitmap_set_all(necs->blend_domain.ptr, true, necs->length);
  }
}
 
void nlasnapshot_ensure_channels(NlaEvalData *eval_data, NlaEvalSnapshot *snapshot)
{
  LISTBASE_FOREACH (NlaEvalChannel *, nec, &eval_data->channels) {
    nlaeval_snapshot_ensure_channel(snapshot, nec);
  }
}
 
void nlasnapshot_blend(NlaEvalData *eval_data,
                       NlaEvalSnapshot *lower_snapshot,
                       NlaEvalSnapshot *upper_snapshot,
                       const short upper_blendmode,
                       const float upper_influence,
                       NlaEvalSnapshot *r_blended_snapshot)
{
  nlaeval_snapshot_ensure_size(r_blended_snapshot, eval_data->num_channels);
 
  const bool zero_upper_influence = IS_EQF(upper_influence, 0.0f);
 
  LISTBASE_FOREACH (NlaEvalChannel *, nec, &eval_data->channels) {
    const int length = nec->base_snapshot.length;
 
    NlaEvalChannelSnapshot *upper_necs = nlaeval_snapshot_get(upper_snapshot, nec->index);
    NlaEvalChannelSnapshot *lower_necs = nlaeval_snapshot_get(lower_snapshot, nec->index);
    if (upper_necs == NULL && lower_necs == NULL) {
      continue;
    }
 
    if (lower_necs == NULL) {
      lower_necs = nlaeval_snapshot_find_channel(lower_snapshot->base, nec);
    }
 
    NlaEvalChannelSnapshot *result_necs = nlaeval_snapshot_ensure_channel(r_blended_snapshot, nec);
 
    memcpy(result_necs->values, lower_necs->values, length * sizeof(float));
    if (upper_necs == NULL || zero_upper_influence) {
      continue;
    }
 
    if (upper_blendmode == NLASTRIP_MODE_COMBINE) {
      const int mix_mode = nec->mix_mode;
      if (mix_mode == NEC_MIX_QUATERNION) {
        if (!BLI_BITMAP_TEST_BOOL(upper_necs->blend_domain.ptr, 0)) {
          continue;
        }
 
        nla_combine_quaternion(
            lower_necs->values, upper_necs->values, upper_influence, result_necs->values);
      }
      else {
        for (int j = 0; j < length; j++) {
          if (!BLI_BITMAP_TEST_BOOL(upper_necs->blend_domain.ptr, j)) {
            continue;
          }
 
          result_necs->values[j] = nla_combine_value(mix_mode,
                                                     nec->base_snapshot.values[j],
                                                     lower_necs->values[j],
                                                     upper_necs->values[j],
                                                     upper_influence);
        }
      }
    }
    else {
      for (int j = 0; j < length; j++) {
        if (!BLI_BITMAP_TEST_BOOL(upper_necs->blend_domain.ptr, j)) {
          continue;
        }
 
        result_necs->values[j] = nla_blend_value(
            upper_blendmode, lower_necs->values[j], upper_necs->values[j], upper_influence);
      }
    }
  }
}
 
/* ---------------------- */
 
NlaKeyframingContext *BKE_animsys_get_nla_keyframing_context(
    struct ListBase *cache,
    struct PointerRNA *ptr,
    struct AnimData *adt,
    const AnimationEvalContext *anim_eval_context)
{
  /* No remapping needed if NLA is off or no action. */
  if ((adt == NULL) || (adt->action == NULL) || (adt->nla_tracks.first == NULL) ||
      (adt->flag & ADT_NLA_EVAL_OFF)) {
    return NULL;
  }
 
  /* No remapping if editing an ordinary Replace action with full influence. */
  if (!(adt->flag & ADT_NLA_EDIT_ON) &&
      (adt->act_blendmode == NLASTRIP_MODE_REPLACE && adt->act_influence == 1.0f)) {
    return NULL;
  }
 
  /* Try to find a cached context. */
  NlaKeyframingContext *ctx = BLI_findptr(cache, adt, offsetof(NlaKeyframingContext, adt));
 
  if (ctx == NULL) {
    /* Allocate and evaluate a new context. */
    ctx = MEM_callocN(sizeof(*ctx), "NlaKeyframingContext");
    ctx->adt = adt;
 
    nlaeval_init(&ctx->lower_eval_data);
    animsys_evaluate_nla_for_keyframing(ptr, adt, anim_eval_context, ctx);
 
    BLI_assert(ELEM(ctx->strip.act, NULL, adt->action));
    BLI_addtail(cache, ctx);
  }
 
  return ctx;
}
 
bool BKE_animsys_nla_remap_keyframe_values(struct NlaKeyframingContext *context,
                                           struct PointerRNA *prop_ptr,
                                           struct PropertyRNA *prop,
                                           float *values,
                                           int count,
                                           int index,
                                           bool *r_force_all)
{
  if (r_force_all != NULL) {
    *r_force_all = false;
  }
 
  /* No context means no correction. */
  if (context == NULL || context->strip.act == NULL) {
    return true;
  }
 
  /* If the strip is not evaluated, it is the same as zero influence. */
  if (context->eval_strip == NULL) {
    return false;
  }
 
  /* Full influence Replace strips also require no correction. */
  int blend_mode = context->strip.blendmode;
  float influence = context->strip.influence;
 
  if (blend_mode == NLASTRIP_MODE_REPLACE && influence == 1.0f) {
    return true;
  }
 
  /* Zero influence is division by zero. */
  if (influence <= 0.0f) {
    return false;
  }
 
  /* Find the evaluation channel for the NLA stack below current strip. */
  NlaEvalChannelKey key = {
      .ptr = *prop_ptr,
      .prop = prop,
  };
  NlaEvalData *const lower_eval_data = &context->lower_eval_data;
  NlaEvalChannel *const lower_nec = nlaevalchan_verify_key(lower_eval_data, NULL, &key);
 
  if ((lower_nec->base_snapshot.length != count)) {
    BLI_assert(!"invalid value count");
    return false;
  }
 
  /* Invert the blending operation to compute the desired strip values. */
  NlaEvalChannelSnapshot *const lower_nec_snapshot = nlaeval_snapshot_find_channel(
      &lower_eval_data->eval_snapshot, lower_nec);
 
  float *lower_values = lower_nec_snapshot->values;
 
  if (blend_mode == NLASTRIP_MODE_COMBINE) {
    /* Quaternion combine handles all sub-channels as a unit. */
    if (lower_nec->mix_mode == NEC_MIX_QUATERNION) {
      if (r_force_all == NULL) {
        return false;
      }
 
      *r_force_all = true;
 
      if (!nla_combine_quaternion_get_inverted_strip_values(
              lower_values, values, influence, values)) {
        return false;
      }
    }
    else {
      float *base_values = lower_nec->base_snapshot.values;
 
      for (int i = 0; i < count; i++) {
        if (ELEM(index, i, -1)) {
          if (!nla_combine_get_inverted_strip_value(lower_nec->mix_mode,
                                                    base_values[i],
                                                    lower_values[i],
                                                    values[i],
                                                    influence,
                                                    &values[i])) {
            return false;
          }
        }
      }
    }
  }
  else {
    for (int i = 0; i < count; i++) {
      if (ELEM(index, i, -1)) {
        if (!nla_blend_get_inverted_strip_value(
                blend_mode, lower_values[i], values[i], influence, &values[i])) {
          return false;
        }
      }
    }
  }
 
  return true;
}
 
void BKE_animsys_free_nla_keyframing_context_cache(struct ListBase *cache)
{
  LISTBASE_FOREACH (NlaKeyframingContext *, ctx, cache) {
    MEM_SAFE_FREE(ctx->eval_strip);
    nlaeval_free(&ctx->lower_eval_data);
  }
 
  BLI_freelistN(cache);
}
 
/* ***************************************** */
/* Overrides System - Public API */
 
/* Evaluate Overrides */
static void animsys_evaluate_overrides(PointerRNA *ptr, AnimData *adt)
{
  AnimOverride *aor;
 
  /* for each override, simply execute... */
  for (aor = adt->overrides.first; aor; aor = aor->next) {
    PathResolvedRNA anim_rna;
    if (BKE_animsys_rna_path_resolve(ptr, aor->rna_path, aor->array_index, &anim_rna)) {
      BKE_animsys_write_to_rna_path(&anim_rna, aor->value);
    }
  }
}
 
/* ***************************************** */
/* Evaluation System - Public API */
 
/* Overview of how this system works:
 * 1) Depsgraph sorts data as necessary, so that data is in an order that means
 *     that all dependencies are resolved before dependents.
 * 2) All normal animation is evaluated, so that drivers have some basis values to
 *    work with
 *    a.  NLA stacks are done first, as the Active Actions act as 'tweaking' tracks
 *        which modify the effects of the NLA-stacks
 *    b.  Active Action is evaluated as per normal, on top of the results of the NLA tracks
 *
 * --------------< often in a separate phase... >------------------
 *
 * 3) Drivers/expressions are evaluated on top of this, in an order where dependencies are
 *    resolved nicely.
 *    Note: it may be necessary to have some tools to handle the cases where some higher-level
 *          drivers are added and cause some problematic dependencies that
 *          didn't exist in the local levels...
 *
 * --------------< always executed >------------------
 *
 * Maintenance of editability of settings (XXX):
 * - In order to ensure that settings that are animated can still be manipulated in the UI without
 *   requiring that keyframes are added to prevent these values from being overwritten,
 *   we use 'overrides'.
 *
 * Unresolved things:
 * - Handling of multi-user settings (i.e. time-offset, group-instancing) -> big cache grids
 *   or nodal system? but stored where?
 * - Multiple-block dependencies
 *   (i.e. drivers for settings are in both local and higher levels) -> split into separate lists?
 *
 * Current Status:
 * - Currently (as of September 2009), overrides we haven't needed to (fully) implement overrides.
 *   However, the code for this is relatively harmless, so is left in the code for now.
 */
 
/* Evaluation loop for evaluation animation data
 *
 * This assumes that the animation-data provided belongs to the ID block in question,
 * and that the flags for which parts of the anim-data settings need to be recalculated
 * have been set already by the depsgraph. Now, we use the recalc
 */
void BKE_animsys_evaluate_animdata(ID *id,
                                   AnimData *adt,
                                   const AnimationEvalContext *anim_eval_context,
                                   eAnimData_Recalc recalc,
                                   const bool flush_to_original)
{
  PointerRNA id_ptr;
 
  /* sanity checks */
  if (ELEM(NULL, id, adt)) {
    return;
  }
 
  /* get pointer to ID-block for RNA to use */
  RNA_id_pointer_create(id, &id_ptr);
 
  /* recalculate keyframe data:
   * - NLA before Active Action, as Active Action behaves as 'tweaking track'
   *   that overrides 'rough' work in NLA
   */
  /* TODO: need to double check that this all works correctly */
  if (recalc & ADT_RECALC_ANIM) {
    /* evaluate NLA data */
    if ((adt->nla_tracks.first) && !(adt->flag & ADT_NLA_EVAL_OFF)) {
      /* evaluate NLA-stack
       * - active action is evaluated as part of the NLA stack as the last item
       */
      animsys_calculate_nla(&id_ptr, adt, anim_eval_context, flush_to_original);
    }
    /* evaluate Active Action only */
    else if (adt->action) {
      animsys_evaluate_action(&id_ptr, adt->action, anim_eval_context, flush_to_original);
    }
  }
 
  /* recalculate drivers
   * - Drivers need to be evaluated afterwards, as they can either override
   *   or be layered on top of existing animation data.
   * - Drivers should be in the appropriate order to be evaluated without problems...
   */
  if (recalc & ADT_RECALC_DRIVERS) {
    animsys_evaluate_drivers(&id_ptr, adt, anim_eval_context);
  }
 
  /* always execute 'overrides'
   * - Overrides allow editing, by overwriting the value(s) set from animation-data, with the
   *   value last set by the user (and not keyframed yet).
   * - Overrides are cleared upon frame change and/or keyframing
   * - It is best that we execute this every time, so that no errors are likely to occur.
   */
  animsys_evaluate_overrides(&id_ptr, adt);
}
 
/* Evaluation of all ID-blocks with Animation Data blocks - Animation Data Only
 *
 * This will evaluate only the animation info available in the animation data-blocks
 * encountered. In order to enforce the system by which some settings controlled by a
 * 'local' (i.e. belonging in the nearest ID-block that setting is related to, not a
 * standard 'root') block are overridden by a larger 'user'
 */
void BKE_animsys_evaluate_all_animation(Main *main, Depsgraph *depsgraph, float ctime)
{
  ID *id;
 
  if (G.debug & G_DEBUG) {
    printf("Evaluate all animation - %f\n", ctime);
  }
 
  const bool flush_to_original = DEG_is_active(depsgraph);
  const AnimationEvalContext anim_eval_context = BKE_animsys_eval_context_construct(depsgraph,
                                                                                    ctime);
 
  /* macros for less typing
   * - only evaluate animation data for id if it has users (and not just fake ones)
   * - whether animdata exists is checked for by the evaluation function, though taking
   *   this outside of the function may make things slightly faster?
   */
#define EVAL_ANIM_IDS(first, aflag) \
  for (id = first; id; id = id->next) { \
    if (ID_REAL_USERS(id) > 0) { \
      AnimData *adt = BKE_animdata_from_id(id); \
      BKE_animsys_evaluate_animdata(id, adt, &anim_eval_context, aflag, flush_to_original); \
    } \
  } \
  (void)0
 
  /* another macro for the "embedded" nodetree cases
   * - this is like EVAL_ANIM_IDS, but this handles the case "embedded nodetrees"
   *   (i.e. scene/material/texture->nodetree) which we need a special exception
   *   for, otherwise they'd get skipped
   * - 'ntp' stands for "node tree parent" = data-block where node tree stuff resides
   */
#define EVAL_ANIM_NODETREE_IDS(first, NtId_Type, aflag) \
  for (id = first; id; id = id->next) { \
    if (ID_REAL_USERS(id) > 0) { \
      AnimData *adt = BKE_animdata_from_id(id); \
      NtId_Type *ntp = (NtId_Type *)id; \
      if (ntp->nodetree) { \
        AnimData *adt2 = BKE_animdata_from_id((ID *)ntp->nodetree); \
        BKE_animsys_evaluate_animdata( \
            &ntp->nodetree->id, adt2, &anim_eval_context, ADT_RECALC_ANIM, flush_to_original); \
      } \
      BKE_animsys_evaluate_animdata(id, adt, &anim_eval_context, aflag, flush_to_original); \
    } \
  } \
  (void)0
 
  /* optimization:
   * when there are no actions, don't go over database and loop over heaps of data-blocks,
   * which should ultimately be empty, since it is not possible for now to have any animation
   * without some actions, and drivers wouldn't get affected by any state changes
   *
   * however, if there are some curves, we will need to make sure that their 'ctime' property gets
   * set correctly, so this optimization must be skipped in that case...
   */
  if (BLI_listbase_is_empty(&main->actions) && BLI_listbase_is_empty(&main->curves)) {
    if (G.debug & G_DEBUG) {
      printf("\tNo Actions, so no animation needs to be evaluated...\n");
    }
 
    return;
  }
 
  /* nodes */
  EVAL_ANIM_IDS(main->nodetrees.first, ADT_RECALC_ANIM);
 
  /* textures */
  EVAL_ANIM_NODETREE_IDS(main->textures.first, Tex, ADT_RECALC_ANIM);
 
  /* lights */
  EVAL_ANIM_NODETREE_IDS(main->lights.first, Light, ADT_RECALC_ANIM);
 
  /* materials */
  EVAL_ANIM_NODETREE_IDS(main->materials.first, Material, ADT_RECALC_ANIM);
 
  /* cameras */
  EVAL_ANIM_IDS(main->cameras.first, ADT_RECALC_ANIM);
 
  /* shapekeys */
  EVAL_ANIM_IDS(main->shapekeys.first, ADT_RECALC_ANIM);
 
  /* metaballs */
  EVAL_ANIM_IDS(main->metaballs.first, ADT_RECALC_ANIM);
 
  /* curves */
  EVAL_ANIM_IDS(main->curves.first, ADT_RECALC_ANIM);
 
  /* armatures */
  EVAL_ANIM_IDS(main->armatures.first, ADT_RECALC_ANIM);
 
  /* lattices */
  EVAL_ANIM_IDS(main->lattices.first, ADT_RECALC_ANIM);
 
  /* meshes */
  EVAL_ANIM_IDS(main->meshes.first, ADT_RECALC_ANIM);
 
  /* particles */
  EVAL_ANIM_IDS(main->particles.first, ADT_RECALC_ANIM);
 
  /* speakers */
  EVAL_ANIM_IDS(main->speakers.first, ADT_RECALC_ANIM);
 
  /* movie clips */
  EVAL_ANIM_IDS(main->movieclips.first, ADT_RECALC_ANIM);
 
  /* linestyles */
  EVAL_ANIM_IDS(main->linestyles.first, ADT_RECALC_ANIM);
 
  /* grease pencil */
  EVAL_ANIM_IDS(main->gpencils.first, ADT_RECALC_ANIM);
 
  /* palettes */
  EVAL_ANIM_IDS(main->palettes.first, ADT_RECALC_ANIM);
 
  /* cache files */
  EVAL_ANIM_IDS(main->cachefiles.first, ADT_RECALC_ANIM);
 
  /* hairs */
  EVAL_ANIM_IDS(main->hairs.first, ADT_RECALC_ANIM);
 
  /* pointclouds */
  EVAL_ANIM_IDS(main->pointclouds.first, ADT_RECALC_ANIM);
 
  /* volumes */
  EVAL_ANIM_IDS(main->volumes.first, ADT_RECALC_ANIM);
 
  /* simulations */
  EVAL_ANIM_IDS(main->simulations.first, ADT_RECALC_ANIM);
 
  /* objects */
  /* ADT_RECALC_ANIM doesn't need to be supplied here, since object AnimData gets
   * this tagged by Depsgraph on framechange. This optimization means that objects
   * linked from other (not-visible) scenes will not need their data calculated.
   */
  EVAL_ANIM_IDS(main->objects.first, 0);
 
  /* masks */
  EVAL_ANIM_IDS(main->masks.first, ADT_RECALC_ANIM);
 
  /* worlds */
  EVAL_ANIM_NODETREE_IDS(main->worlds.first, World, ADT_RECALC_ANIM);
 
  /* scenes */
  EVAL_ANIM_NODETREE_IDS(main->scenes.first, Scene, ADT_RECALC_ANIM);
}
 
/* ***************************************** */
 
/* ************** */
/* Evaluation API */
 
void BKE_animsys_eval_animdata(Depsgraph *depsgraph, ID *id)
{
  float ctime = DEG_get_ctime(depsgraph);
  AnimData *adt = BKE_animdata_from_id(id);
  /* XXX: this is only needed for flushing RNA updates,
   * which should get handled as part of the dependency graph instead. */
  DEG_debug_print_eval_time(depsgraph, __func__, id->name, id, ctime);
  const bool flush_to_original = DEG_is_active(depsgraph);
 
  const AnimationEvalContext anim_eval_context = BKE_animsys_eval_context_construct(depsgraph,
                                                                                    ctime);
  BKE_animsys_evaluate_animdata(id, adt, &anim_eval_context, ADT_RECALC_ANIM, flush_to_original);
}
 
void BKE_animsys_update_driver_array(ID *id)
{
  AnimData *adt = BKE_animdata_from_id(id);
 
  /* Runtime driver map to avoid O(n^2) lookups in BKE_animsys_eval_driver.
   * Ideally the depsgraph could pass a pointer to the COW driver directly,
   * but this is difficult in the current design. */
  if (adt && adt->drivers.first) {
    BLI_assert(!adt->driver_array);
 
    int num_drivers = BLI_listbase_count(&adt->drivers);
    adt->driver_array = MEM_mallocN(sizeof(FCurve *) * num_drivers, "adt->driver_array");
 
    int driver_index = 0;
    LISTBASE_FOREACH (FCurve *, fcu, &adt->drivers) {
      adt->driver_array[driver_index++] = fcu;
    }
  }
}
 
void BKE_animsys_eval_driver(Depsgraph *depsgraph, ID *id, int driver_index, FCurve *fcu_orig)
{
  BLI_assert(fcu_orig != NULL);
 
  /* TODO(sergey): De-duplicate with BKE animsys. */
  PointerRNA id_ptr;
  bool ok = false;
 
  /* Lookup driver, accelerated with driver array map. */
  const AnimData *adt = BKE_animdata_from_id(id);
  FCurve *fcu;
 
  if (adt->driver_array) {
    fcu = adt->driver_array[driver_index];
  }
  else {
    fcu = BLI_findlink(&adt->drivers, driver_index);
  }
 
  DEG_debug_print_eval_subdata_index(
      depsgraph, __func__, id->name, id, "fcu", fcu->rna_path, fcu, fcu->array_index);
 
  RNA_id_pointer_create(id, &id_ptr);
 
  /* check if this driver's curve should be skipped */
  if ((fcu->flag & (FCURVE_MUTED | FCURVE_DISABLED)) == 0) {
    /* check if driver itself is tagged for recalculation */
    /* XXX driver recalc flag is not set yet by depsgraph! */
    ChannelDriver *driver_orig = fcu_orig->driver;
    if ((driver_orig) && !(driver_orig->flag & DRIVER_FLAG_INVALID)) {
      /* evaluate this using values set already in other places
       * NOTE: for 'layering' option later on, we should check if we should remove old value before
       * adding new to only be done when drivers only changed */
      // printf("\told val = %f\n", fcu->curval);
 
      PathResolvedRNA anim_rna;
      if (BKE_animsys_rna_path_resolve(&id_ptr, fcu->rna_path, fcu->array_index, &anim_rna)) {
        /* Evaluate driver, and write results to COW-domain destination */
        const float ctime = DEG_get_ctime(depsgraph);
        const AnimationEvalContext anim_eval_context = BKE_animsys_eval_context_construct(
            depsgraph, ctime);
        const float curval = calculate_fcurve(&anim_rna, fcu, &anim_eval_context);
        ok = BKE_animsys_write_to_rna_path(&anim_rna, curval);
 
        /* Flush results & status codes to original data for UI (T59984) */
        if (ok && DEG_is_active(depsgraph)) {
          animsys_write_orig_anim_rna(&id_ptr, fcu->rna_path, fcu->array_index, curval);
 
          /* curval is displayed in the UI, and flag contains error-status codes */
          fcu_orig->curval = fcu->curval;
          driver_orig->curval = fcu->driver->curval;
          driver_orig->flag = fcu->driver->flag;
 
          DriverVar *dvar_orig = driver_orig->variables.first;
          DriverVar *dvar = fcu->driver->variables.first;
          for (; dvar_orig && dvar; dvar_orig = dvar_orig->next, dvar = dvar->next) {
            DriverTarget *dtar_orig = &dvar_orig->targets[0];
            DriverTarget *dtar = &dvar->targets[0];
            for (int i = 0; i < MAX_DRIVER_TARGETS; i++, dtar_orig++, dtar++) {
              dtar_orig->flag = dtar->flag;
            }
 
            dvar_orig->curval = dvar->curval;
            dvar_orig->flag = dvar->flag;
          }
        }
      }
 
      /* set error-flag if evaluation failed */
      if (ok == 0) {
        CLOG_WARN(&LOG, "invalid driver - %s[%d]", fcu->rna_path, fcu->array_index);
        driver_orig->flag |= DRIVER_FLAG_INVALID;
      }
    }
  }
}