virtualx-engine/scene/animation/skeleton_ik.cpp
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

592 lines
20 KiB
C++

/**************************************************************************/
/* skeleton_ik.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
/**
* @author AndreaCatania
*/
#include "skeleton_ik.h"
#ifndef _3D_DISABLED
FabrikInverseKinematic::ChainItem *FabrikInverseKinematic::ChainItem::find_child(const BoneId p_bone_id) {
for (int i = children.size() - 1; 0 <= i; --i) {
if (p_bone_id == children[i].bone) {
return &children.write[i];
}
}
return nullptr;
}
FabrikInverseKinematic::ChainItem *FabrikInverseKinematic::ChainItem::add_child(const BoneId p_bone_id) {
const int infant_child_id = children.size();
children.resize(infant_child_id + 1);
children.write[infant_child_id].bone = p_bone_id;
children.write[infant_child_id].parent_item = this;
return &children.write[infant_child_id];
}
/// Build a chain that starts from the root to tip
bool FabrikInverseKinematic::build_chain(Task *p_task, bool p_force_simple_chain) {
ERR_FAIL_COND_V(-1 == p_task->root_bone, false);
Chain &chain(p_task->chain);
chain.tips.resize(p_task->end_effectors.size());
chain.chain_root.bone = p_task->root_bone;
chain.chain_root.initial_transform = p_task->skeleton->get_bone_global_pose(chain.chain_root.bone);
chain.chain_root.current_pos = chain.chain_root.initial_transform.origin;
chain.middle_chain_item = nullptr;
// Holds all IDs that are composing a single chain in reverse order
Vector<BoneId> chain_ids;
// This is used to know the chain size
int sub_chain_size;
// Resize only one time in order to fit all joints for performance reason
chain_ids.resize(p_task->skeleton->get_bone_count());
for (int x = p_task->end_effectors.size() - 1; 0 <= x; --x) {
const EndEffector *ee(&p_task->end_effectors[x]);
ERR_FAIL_COND_V(p_task->root_bone >= ee->tip_bone, false);
ERR_FAIL_INDEX_V(ee->tip_bone, p_task->skeleton->get_bone_count(), false);
sub_chain_size = 0;
// Picks all IDs that composing a single chain in reverse order (except the root)
BoneId chain_sub_tip(ee->tip_bone);
while (chain_sub_tip > p_task->root_bone) {
chain_ids.write[sub_chain_size++] = chain_sub_tip;
chain_sub_tip = p_task->skeleton->get_bone_parent(chain_sub_tip);
}
BoneId middle_chain_item_id = (((float)sub_chain_size) * 0.5);
// Build chain by reading chain ids in reverse order
// For each chain item id will be created a ChainItem if doesn't exists
ChainItem *sub_chain(&chain.chain_root);
for (int i = sub_chain_size - 1; 0 <= i; --i) {
ChainItem *child_ci(sub_chain->find_child(chain_ids[i]));
if (!child_ci) {
child_ci = sub_chain->add_child(chain_ids[i]);
child_ci->initial_transform = p_task->skeleton->get_bone_global_pose(child_ci->bone);
child_ci->current_pos = child_ci->initial_transform.origin;
if (child_ci->parent_item) {
child_ci->length = (child_ci->current_pos - child_ci->parent_item->current_pos).length();
}
}
sub_chain = child_ci;
if (middle_chain_item_id == i) {
chain.middle_chain_item = child_ci;
}
}
if (!middle_chain_item_id) {
chain.middle_chain_item = nullptr;
}
// Initialize current tip
chain.tips.write[x].chain_item = sub_chain;
chain.tips.write[x].end_effector = ee;
if (p_force_simple_chain) {
// NOTE:
// This is an "hack" that force to create only one tip per chain since the solver of multi tip (end effector)
// is not yet created.
// Remove this code when this is done
break;
}
}
return true;
}
void FabrikInverseKinematic::solve_simple(Task *p_task, bool p_solve_magnet, Vector3 p_origin_pos) {
real_t distance_to_goal(1e4);
real_t previous_distance_to_goal(0);
int can_solve(p_task->max_iterations);
while (distance_to_goal > p_task->min_distance && Math::abs(previous_distance_to_goal - distance_to_goal) > 0.005 && can_solve) {
previous_distance_to_goal = distance_to_goal;
--can_solve;
solve_simple_backwards(p_task->chain, p_solve_magnet);
solve_simple_forwards(p_task->chain, p_solve_magnet, p_origin_pos);
distance_to_goal = (p_task->chain.tips[0].chain_item->current_pos - p_task->chain.tips[0].end_effector->goal_transform.origin).length();
}
}
void FabrikInverseKinematic::solve_simple_backwards(Chain &r_chain, bool p_solve_magnet) {
if (p_solve_magnet && !r_chain.middle_chain_item) {
return;
}
Vector3 goal;
ChainItem *sub_chain_tip;
if (p_solve_magnet) {
goal = r_chain.magnet_position;
sub_chain_tip = r_chain.middle_chain_item;
} else {
goal = r_chain.tips[0].end_effector->goal_transform.origin;
sub_chain_tip = r_chain.tips[0].chain_item;
}
while (sub_chain_tip) {
sub_chain_tip->current_pos = goal;
if (sub_chain_tip->parent_item) {
// Not yet in the chain root
// So calculate next goal location
const Vector3 look_parent((sub_chain_tip->parent_item->current_pos - sub_chain_tip->current_pos).normalized());
goal = sub_chain_tip->current_pos + (look_parent * sub_chain_tip->length);
// [TODO] Constraints goes here
}
sub_chain_tip = sub_chain_tip->parent_item;
}
}
void FabrikInverseKinematic::solve_simple_forwards(Chain &r_chain, bool p_solve_magnet, Vector3 p_origin_pos) {
if (p_solve_magnet && !r_chain.middle_chain_item) {
return;
}
ChainItem *sub_chain_root(&r_chain.chain_root);
Vector3 origin = p_origin_pos;
while (sub_chain_root) { // Reach the tip
sub_chain_root->current_pos = origin;
if (!sub_chain_root->children.empty()) {
ChainItem &child(sub_chain_root->children.write[0]);
// Is not tip
// So calculate next origin location
// Look child
sub_chain_root->current_ori = (child.current_pos - sub_chain_root->current_pos).normalized();
origin = sub_chain_root->current_pos + (sub_chain_root->current_ori * child.length);
// [TODO] Constraints goes here
if (p_solve_magnet && sub_chain_root == r_chain.middle_chain_item) {
// In case of magnet solving this is the tip
sub_chain_root = nullptr;
} else {
sub_chain_root = &child;
}
} else {
// Is tip
sub_chain_root = nullptr;
}
}
}
FabrikInverseKinematic::Task *FabrikInverseKinematic::create_simple_task(Skeleton *p_sk, BoneId root_bone, BoneId tip_bone, const Transform &goal_transform) {
FabrikInverseKinematic::EndEffector ee;
ee.tip_bone = tip_bone;
Task *task(memnew(Task));
task->skeleton = p_sk;
task->root_bone = root_bone;
task->end_effectors.push_back(ee);
task->goal_global_transform = goal_transform;
if (!build_chain(task)) {
free_task(task);
return nullptr;
}
return task;
}
void FabrikInverseKinematic::free_task(Task *p_task) {
if (p_task) {
memdelete(p_task);
}
}
void FabrikInverseKinematic::set_goal(Task *p_task, const Transform &p_goal) {
p_task->goal_global_transform = p_goal;
}
void FabrikInverseKinematic::make_goal(Task *p_task, const Transform &p_inverse_transf, real_t blending_delta) {
if (blending_delta >= 0.99f) {
// Update the end_effector (local transform) without blending
p_task->end_effectors.write[0].goal_transform = p_inverse_transf * p_task->goal_global_transform;
} else {
// End effector in local transform
const Transform end_effector_pose(p_task->skeleton->get_bone_global_pose_no_override(p_task->end_effectors[0].tip_bone));
// Update the end_effector (local transform) by blending with current pose
p_task->end_effectors.write[0].goal_transform = end_effector_pose.interpolate_with(p_inverse_transf * p_task->goal_global_transform, blending_delta);
}
}
void FabrikInverseKinematic::solve(Task *p_task, real_t blending_delta, bool override_tip_basis, bool p_use_magnet, const Vector3 &p_magnet_position) {
if (blending_delta <= 0.01f) {
// Before skipping, make sure we undo the global pose overrides
ChainItem *ci(&p_task->chain.chain_root);
while (ci) {
p_task->skeleton->set_bone_global_pose_override(ci->bone, ci->initial_transform, 0.0, false);
if (!ci->children.empty()) {
ci = &ci->children.write[0];
} else {
ci = nullptr;
}
}
return; // Skip solving
}
// Update the initial root transform so its synced with any animation changes
_update_chain(p_task->skeleton, &p_task->chain.chain_root);
p_task->skeleton->set_bone_global_pose_override(p_task->chain.chain_root.bone, Transform(), 0.0, false);
Vector3 origin_pos = p_task->skeleton->get_bone_global_pose(p_task->chain.chain_root.bone).origin;
make_goal(p_task, p_task->skeleton->get_global_transform().affine_inverse(), blending_delta);
if (p_use_magnet && p_task->chain.middle_chain_item) {
p_task->chain.magnet_position = p_task->chain.middle_chain_item->initial_transform.origin.linear_interpolate(p_magnet_position, blending_delta);
solve_simple(p_task, true, origin_pos);
}
solve_simple(p_task, false, origin_pos);
// Assign new bone position.
ChainItem *ci(&p_task->chain.chain_root);
while (ci) {
Transform new_bone_pose(ci->initial_transform);
new_bone_pose.origin = ci->current_pos;
if (!ci->children.empty()) {
/// Rotate basis
const Vector3 initial_ori((ci->children[0].initial_transform.origin - ci->initial_transform.origin).normalized());
const Vector3 rot_axis(initial_ori.cross(ci->current_ori).normalized());
if (rot_axis[0] != 0 && rot_axis[1] != 0 && rot_axis[2] != 0) {
const real_t rot_angle(Math::acos(CLAMP(initial_ori.dot(ci->current_ori), -1, 1)));
new_bone_pose.basis.rotate(rot_axis, rot_angle);
}
} else {
// Set target orientation to tip
if (override_tip_basis)
new_bone_pose.basis = p_task->chain.tips[0].end_effector->goal_transform.basis;
else
new_bone_pose.basis = new_bone_pose.basis * p_task->chain.tips[0].end_effector->goal_transform.basis;
}
// IK should not affect scale, so undo any scaling
new_bone_pose.basis.orthonormalize();
new_bone_pose.basis.scale(p_task->skeleton->get_bone_global_pose(ci->bone).basis.get_scale());
p_task->skeleton->set_bone_global_pose_override(ci->bone, new_bone_pose, 1.0, true);
if (!ci->children.empty()) {
ci = &ci->children.write[0];
} else {
ci = nullptr;
}
}
}
void FabrikInverseKinematic::_update_chain(const Skeleton *p_sk, ChainItem *p_chain_item) {
if (!p_chain_item) {
return;
}
p_chain_item->initial_transform = p_sk->get_bone_global_pose_no_override(p_chain_item->bone);
p_chain_item->current_pos = p_chain_item->initial_transform.origin;
ChainItem *items = p_chain_item->children.ptrw();
for (int i = 0; i < p_chain_item->children.size(); i += 1) {
_update_chain(p_sk, items + i);
}
}
void SkeletonIK::_validate_property(PropertyInfo &property) const {
if (property.name == "root_bone" || property.name == "tip_bone") {
if (skeleton) {
String names("--,");
for (int i = 0; i < skeleton->get_bone_count(); i++) {
if (i > 0) {
names += ",";
}
names += skeleton->get_bone_name(i);
}
property.hint = PROPERTY_HINT_ENUM;
property.hint_string = names;
} else {
property.hint = PROPERTY_HINT_NONE;
property.hint_string = "";
}
}
}
void SkeletonIK::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_root_bone", "root_bone"), &SkeletonIK::set_root_bone);
ClassDB::bind_method(D_METHOD("get_root_bone"), &SkeletonIK::get_root_bone);
ClassDB::bind_method(D_METHOD("set_tip_bone", "tip_bone"), &SkeletonIK::set_tip_bone);
ClassDB::bind_method(D_METHOD("get_tip_bone"), &SkeletonIK::get_tip_bone);
ClassDB::bind_method(D_METHOD("set_interpolation", "interpolation"), &SkeletonIK::set_interpolation);
ClassDB::bind_method(D_METHOD("get_interpolation"), &SkeletonIK::get_interpolation);
ClassDB::bind_method(D_METHOD("set_target_transform", "target"), &SkeletonIK::set_target_transform);
ClassDB::bind_method(D_METHOD("get_target_transform"), &SkeletonIK::get_target_transform);
ClassDB::bind_method(D_METHOD("set_target_node", "node"), &SkeletonIK::set_target_node);
ClassDB::bind_method(D_METHOD("get_target_node"), &SkeletonIK::get_target_node);
ClassDB::bind_method(D_METHOD("set_override_tip_basis", "override"), &SkeletonIK::set_override_tip_basis);
ClassDB::bind_method(D_METHOD("is_override_tip_basis"), &SkeletonIK::is_override_tip_basis);
ClassDB::bind_method(D_METHOD("set_use_magnet", "use"), &SkeletonIK::set_use_magnet);
ClassDB::bind_method(D_METHOD("is_using_magnet"), &SkeletonIK::is_using_magnet);
ClassDB::bind_method(D_METHOD("set_magnet_position", "local_position"), &SkeletonIK::set_magnet_position);
ClassDB::bind_method(D_METHOD("get_magnet_position"), &SkeletonIK::get_magnet_position);
ClassDB::bind_method(D_METHOD("get_parent_skeleton"), &SkeletonIK::get_parent_skeleton);
ClassDB::bind_method(D_METHOD("is_running"), &SkeletonIK::is_running);
ClassDB::bind_method(D_METHOD("set_min_distance", "min_distance"), &SkeletonIK::set_min_distance);
ClassDB::bind_method(D_METHOD("get_min_distance"), &SkeletonIK::get_min_distance);
ClassDB::bind_method(D_METHOD("set_max_iterations", "iterations"), &SkeletonIK::set_max_iterations);
ClassDB::bind_method(D_METHOD("get_max_iterations"), &SkeletonIK::get_max_iterations);
ClassDB::bind_method(D_METHOD("start", "one_time"), &SkeletonIK::start, DEFVAL(false));
ClassDB::bind_method(D_METHOD("stop"), &SkeletonIK::stop);
ADD_PROPERTY(PropertyInfo(Variant::STRING, "root_bone"), "set_root_bone", "get_root_bone");
ADD_PROPERTY(PropertyInfo(Variant::STRING, "tip_bone"), "set_tip_bone", "get_tip_bone");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "interpolation", PROPERTY_HINT_RANGE, "0,1,0.001"), "set_interpolation", "get_interpolation");
ADD_PROPERTY(PropertyInfo(Variant::TRANSFORM, "target"), "set_target_transform", "get_target_transform");
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "override_tip_basis"), "set_override_tip_basis", "is_override_tip_basis");
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_magnet"), "set_use_magnet", "is_using_magnet");
ADD_PROPERTY(PropertyInfo(Variant::VECTOR3, "magnet"), "set_magnet_position", "get_magnet_position");
ADD_PROPERTY(PropertyInfo(Variant::NODE_PATH, "target_node"), "set_target_node", "get_target_node");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "min_distance"), "set_min_distance", "get_min_distance");
ADD_PROPERTY(PropertyInfo(Variant::INT, "max_iterations"), "set_max_iterations", "get_max_iterations");
}
void SkeletonIK::_notification(int p_what) {
switch (p_what) {
case NOTIFICATION_ENTER_TREE: {
skeleton = Object::cast_to<Skeleton>(get_parent());
set_process_priority(1);
reload_chain();
} break;
case NOTIFICATION_INTERNAL_PROCESS: {
if (target_node_override) {
reload_goal();
}
_solve_chain();
} break;
case NOTIFICATION_EXIT_TREE: {
reload_chain();
} break;
}
}
SkeletonIK::SkeletonIK() :
interpolation(1),
override_tip_basis(true),
use_magnet(false),
min_distance(0.01),
max_iterations(10),
skeleton(nullptr),
target_node_override(nullptr),
task(nullptr) {
}
SkeletonIK::~SkeletonIK() {
FabrikInverseKinematic::free_task(task);
task = nullptr;
}
void SkeletonIK::set_root_bone(const StringName &p_root_bone) {
root_bone = p_root_bone;
reload_chain();
}
StringName SkeletonIK::get_root_bone() const {
return root_bone;
}
void SkeletonIK::set_tip_bone(const StringName &p_tip_bone) {
tip_bone = p_tip_bone;
reload_chain();
}
StringName SkeletonIK::get_tip_bone() const {
return tip_bone;
}
void SkeletonIK::set_interpolation(real_t p_interpolation) {
interpolation = p_interpolation;
}
real_t SkeletonIK::get_interpolation() const {
return interpolation;
}
void SkeletonIK::set_target_transform(const Transform &p_target) {
target = p_target;
reload_goal();
}
const Transform &SkeletonIK::get_target_transform() const {
return target;
}
void SkeletonIK::set_target_node(const NodePath &p_node) {
target_node_path_override = p_node;
target_node_override = nullptr;
reload_goal();
}
NodePath SkeletonIK::get_target_node() {
return target_node_path_override;
}
void SkeletonIK::set_override_tip_basis(bool p_override) {
override_tip_basis = p_override;
}
bool SkeletonIK::is_override_tip_basis() const {
return override_tip_basis;
}
void SkeletonIK::set_use_magnet(bool p_use) {
use_magnet = p_use;
}
bool SkeletonIK::is_using_magnet() const {
return use_magnet;
}
void SkeletonIK::set_magnet_position(const Vector3 &p_local_position) {
magnet_position = p_local_position;
}
const Vector3 &SkeletonIK::get_magnet_position() const {
return magnet_position;
}
void SkeletonIK::set_min_distance(real_t p_min_distance) {
min_distance = p_min_distance;
}
void SkeletonIK::set_max_iterations(int p_iterations) {
max_iterations = p_iterations;
}
bool SkeletonIK::is_running() {
return is_processing_internal();
}
void SkeletonIK::start(bool p_one_time) {
if (p_one_time) {
set_process_internal(false);
if (target_node_override) {
reload_goal();
}
_solve_chain();
} else {
set_process_internal(true);
}
}
void SkeletonIK::stop() {
set_process_internal(false);
if (skeleton) {
skeleton->clear_bones_global_pose_override();
}
}
Transform SkeletonIK::_get_target_transform() {
if (!target_node_override && !target_node_path_override.is_empty()) {
target_node_override = Object::cast_to<Spatial>(get_node(target_node_path_override));
}
if (target_node_override && target_node_override->is_inside_tree()) {
// Make sure to use the interpolated transform as target.
// This will pass through to get_global_transform() when physics interpolation is off, and when using interpolation,
// ensure that the target matches the interpolated visual position of the target when updating the IK each frame.
return target_node_override->get_global_transform_interpolated();
} else {
return target;
}
}
void SkeletonIK::reload_chain() {
FabrikInverseKinematic::free_task(task);
task = nullptr;
if (!skeleton) {
return;
}
task = FabrikInverseKinematic::create_simple_task(skeleton, skeleton->find_bone(root_bone), skeleton->find_bone(tip_bone), _get_target_transform());
if (task) {
task->max_iterations = max_iterations;
task->min_distance = min_distance;
}
}
void SkeletonIK::reload_goal() {
if (!task) {
return;
}
FabrikInverseKinematic::set_goal(task, _get_target_transform());
}
void SkeletonIK::_solve_chain() {
if (!task) {
return;
}
FabrikInverseKinematic::solve(task, interpolation, override_tip_basis, use_magnet, magnet_position);
}
#endif // _3D_DISABLED