godot/scene/animation/skeleton_ik.cpp
2018-08-26 12:41:20 +02:00

562 lines
18 KiB
C++

/*************************************************************************/
/* skeleton_ik.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md) */
/* */
/* 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 = childs.size() - 1; 0 <= i; --i) {
if (p_bone_id == childs[i].bone) {
return &childs.write[i];
}
}
return NULL;
}
FabrikInverseKinematic::ChainItem *FabrikInverseKinematic::ChainItem::add_child(const BoneId p_bone_id) {
const int infant_child_id = childs.size();
childs.resize(infant_child_id + 1);
childs.write[infant_child_id].bone = p_bone_id;
childs.write[infant_child_id].parent_item = this;
return &childs.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.chain_root.pb = p_task->skeleton->get_physical_bone(chain.chain_root.bone);
chain.middle_chain_item = NULL;
// 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->pb = p_task->skeleton->get_physical_bone(child_ci->bone);
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 = NULL;
// 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::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(p_chain_item->bone);
p_chain_item->current_pos = p_chain_item->initial_transform.origin;
for (int i = p_chain_item->childs.size() - 1; 0 <= i; --i) {
update_chain(p_sk, &p_chain_item->childs.write[i]);
}
}
void FabrikInverseKinematic::solve_simple(Task *p_task, bool p_solve_magnet) {
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);
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) {
if (p_solve_magnet && !r_chain.middle_chain_item) {
return;
}
ChainItem *sub_chain_root(&r_chain.chain_root);
Vector3 origin(r_chain.chain_root.initial_transform.origin);
while (sub_chain_root) { // Reach the tip
sub_chain_root->current_pos = origin;
if (!sub_chain_root->childs.empty()) {
ChainItem &child(sub_chain_root->childs.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 = NULL;
} else {
sub_chain_root = &child;
}
} else {
// Is tip
sub_chain_root = NULL;
}
}
}
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 NULL;
}
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(p_task->end_effectors.write[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 p_use_magnet, const Vector3 &p_magnet_position) {
if (blending_delta <= 0.01f) {
return; // Skip solving
}
make_goal(p_task, p_task->skeleton->get_global_transform().affine_inverse().scaled(p_task->skeleton->get_global_transform().get_basis().get_scale()), blending_delta);
update_chain(p_task->skeleton, &p_task->chain.chain_root);
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);
}
solve_simple(p_task, false);
// 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->childs.empty()) {
/// Rotate basis
const Vector3 initial_ori((ci->childs[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
new_bone_pose.basis = p_task->chain.tips[0].end_effector->goal_transform.basis;
}
p_task->skeleton->set_bone_global_pose(ci->bone, new_bone_pose);
if (!ci->childs.empty())
ci = &ci->childs.write[0];
else
ci = NULL;
}
}
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_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, "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());
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() :
Node(),
interpolation(1),
skeleton(NULL),
target_node_override(NULL),
use_magnet(false),
min_distance(0.01),
max_iterations(10),
task(NULL) {
set_process_priority(1);
}
SkeletonIK::~SkeletonIK() {
FabrikInverseKinematic::free_task(task);
task = NULL;
}
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 = NULL;
reload_goal();
}
NodePath SkeletonIK::get_target_node() {
return target_node_path_override;
}
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);
_solve_chain();
} else {
set_process_internal(true);
}
}
void SkeletonIK::stop() {
set_process_internal(false);
}
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)
return target_node_override->get_global_transform();
else
return target;
}
void SkeletonIK::reload_chain() {
FabrikInverseKinematic::free_task(task);
task = NULL;
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, use_magnet, magnet_position);
}
#endif // _3D_DISABLED