fbx_import_util.hh

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/* SPDX-FileCopyrightText: 2025 Blender Authors
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

 
#pragma once
 
#include "BLI_map.hh"
#include "BLI_set.hh"
 
#include "ufbx.h"
 
struct ID;
struct Object;
struct Key;
struct Material;
struct bPoseChannel;
 
namespace blender::io::fbx {
 
const char *get_fbx_name(const ufbx_string &name, const char *def = "Untitled");
 
struct FbxElementMapping {
  Set<Object *> imported_objects;
  Map<const ufbx_element *, Object *> el_to_object;
  Map<const ufbx_element *, Key *> el_to_shape_key;
  Map<const ufbx_material *, Material *> mat_to_material;
  Map<const ufbx_node *, Object *> bone_to_armature;
 
  /* For the armatures we create, for different use cases we need transform
   * from world space to the root bone, either in posed transform or in
   * node transform. */
  Map<const Object *, ufbx_matrix> armature_world_to_arm_pose_matrix;
  Map<const Object *, ufbx_matrix> armature_world_to_arm_node_matrix;
 
  /* Which FBX bone nodes got turned into actual armature bones (not all of them
   * always are; in some cases root bone is the armature object itself). */
  Set<const ufbx_node *> node_is_blender_bone;
 
  /* Mapping of ufbx node to object name used within blender. If names are too long
   * or duplicate, they might not match what was in FBX file. */
  Map<const ufbx_node *, std::string> node_to_name;
  /* Bone node to "bind matrix", i.e. matrix that transforms from bone (in skin bind pose) local
   * space to world space. This records bone pose or skin cluster bind matrix (skin cluster taking
   * precedence if it exists). */
  Map<const ufbx_node *, ufbx_matrix> bone_to_bind_matrix;
  Map<const ufbx_node *, ufbx_real> bone_to_length;
  Set<const ufbx_node *> bone_is_skinned;
  ufbx_matrix global_conv_matrix;
 
  ufbx_matrix get_node_bind_matrix(const ufbx_node *node) const
  {
    return this->bone_to_bind_matrix.lookup_default(node, node->geometry_to_world);
  }
 
  ufbx_matrix calc_local_bind_matrix(const ufbx_node *bone_node,
                                     const ufbx_matrix &world_to_arm) const
  {
    ufbx_matrix res = this->get_node_bind_matrix(bone_node);
    ufbx_matrix parent_inv_mtx;
    if (bone_node->parent != nullptr && !bone_node->parent->is_root) {
      ufbx_matrix parent_mtx = this->get_node_bind_matrix(bone_node->parent);
      parent_inv_mtx = ufbx_matrix_invert(&parent_mtx);
    }
    else {
      parent_inv_mtx = world_to_arm;
    }
    res = ufbx_matrix_mul(&parent_inv_mtx, &res);
    return res;
  }
};
 
void matrix_to_m44(const ufbx_matrix &src, float dst[4][4]);
void ufbx_matrix_to_obj(const ufbx_matrix &mtx, Object *obj);
void node_matrix_to_obj(const ufbx_node *node, Object *obj, const FbxElementMapping &mapping);
void read_custom_properties(const ufbx_props &props, ID &id, bool enums_as_strings);
void read_custom_properties(const ufbx_props &props, bPoseChannel &pchan, bool enums_as_strings);
 
ufbx_matrix calc_bone_pose_matrix(const ufbx_transform &local_xform,
                                  const ufbx_node &node,
                                  const ufbx_matrix &local_bind_inv_matrix);
 
//@TODO remove debug file print once things are working properly
// #define FBX_DEBUG_PRINT
 
#ifdef FBX_DEBUG_PRINT
extern FILE *g_debug_file;
 
inline double adjf(double f)
{
  if (fabs(f) < 0.0005) {
    return 0.0;
  }
  return f;
}
 
void print_matrix(const ufbx_matrix &m);
#endif
 
}  // namespace blender::io::fbx