feat: implemented heal action and goal

godot/AI/maintain_health.tres

@@ -0,0 +1,9 @@
+[gd_resource type="Goal" format=3 uid="uid://btv8ultseri3q"]
+
+[resource]
+requirements_dict = {
+"is_health_safe": false
+}
+desired_state_dict = {
+"is_health_safe": true
+}

godot/GameObjects/enemy_unit.tscn

@@ -1,6 +1,7 @@
-[gd_scene load_steps=8 format=3 uid="uid://ba17jrcaduowj"]
+[gd_scene load_steps=9 format=3 uid="uid://ba17jrcaduowj"]
 
 [ext_resource type="Goal" uid="uid://b4i4e34046n44" path="res://AI/defeat_enemy_unit.tres" id="1_b1qo1"]
+[ext_resource type="Goal" uid="uid://btv8ultseri3q" path="res://AI/maintain_health.tres" id="2_k42dl"]
 [ext_resource type="AnimationLibrary" uid="uid://crkh5gahl2ci6" path="res://Animation/bean_characters.res" id="2_lrpu6"]
 
 [sub_resource type="SphereShape3D" id="SphereShape3D_5pqvg"]
@@ -24,11 +25,11 @@ collision_layer = 6
 collision_mask = 0
 
 [node name="ActorWorldState" type="EnemyWorldState" parent="."]
-editor_available_goals = [ExtResource("1_b1qo1")]
+editor_available_goals = [ExtResource("2_k42dl"), ExtResource("1_b1qo1")]
 unique_name_in_owner = true
 
 [node name="Planner" type="Planner" parent="."]
-actions_inspector = [3, 2, 4]
+actions_inspector = [3, 2, 4, 5]
 unique_name_in_owner = true
 
 [node name="EntityHealth" type="EntityHealth" parent="."]
@@ -63,7 +64,7 @@ transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1.4512, 0)
 transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1.31501, 0)
 
 [node name="CollisionShape3D" type="CollisionShape3D" parent="."]
-transform = Transform3D(1, 0, 0, 0, 0.999222, -0.0394342, 0, 0.0394342, 0.999222, 0, 1.01253, 0.443459)
+transform = Transform3D(1, 0, 0, 0, 0.999222, -0.0394342, 0, 0.0394342, 0.999222, 0, 1.013, 0)
 shape = SubResource("SphereShape3D_drlm2")
 
 [node name="MeshInstance3D" type="MeshInstance3D" parent="."]

src/enemy_world_state.cpp

@@ -19,16 +19,13 @@ void EnemyWorldState::_ready() {
     this->awareness_area->connect("body_entered", callable_mp(this, &EnemyWorldState::on_awareness_entered));
     this->awareness_area->connect("body_exited", callable_mp(this, &EnemyWorldState::on_awareness_exited));
     this->health = this->get_node<EntityHealth>("%EntityHealth");
-    if(this->health == nullptr)
     this->health->connect("damage", callable_mp(this, &EnemyWorldState::on_damaged));
 }
 
 void EnemyWorldState::on_awareness_entered(gd::Node3D *node) {
-    gd::UtilityFunctions::print("1) object entered awareness");
     Unit *unit{gd::Object::cast_to<Unit>(node)};
     if(unit == nullptr) return;
     if(unit == this->parent_unit) return;
-    gd::UtilityFunctions::print("2) object was Unit");
     this->known_enemies.push_back(unit);
     this->try_set_target(this->select_target_from_known());
 }
@@ -82,17 +79,15 @@ gd::Ref<goap::Goal> EnemyWorldState::get_goal_for_target(Unit *unit) {
 }
 
 void EnemyWorldState::try_set_target(Unit *unit) {
-    gd::UtilityFunctions::print("3) selecting goal");
     gd::Ref<goap::Goal> goal{this->get_goal_for_target(unit)};
-    if(!goal.is_valid()) return;
+    if(goal.is_valid())
-    gd::UtilityFunctions::print("4) selected goal ", goal->get_path());
         this->parent_unit->set_target_goal(unit, goal);
 }
 
 void EnemyWorldState::set_editor_available_goals(gd::Array array) {
     this->available_goals.clear();
     while(!array.is_empty()) {
-        gd::Ref<goap::Goal> goal{array.pop_back()};
+        gd::Ref<goap::Goal> goal{array.pop_front()};
         this->available_goals.push_back(goal);
     }
 }

src/entity_health.cpp

@@ -4,6 +4,9 @@
 
 void EntityHealth::_bind_methods() {
 #define CLASSNAME EntityHealth
+    GDFUNCTION_ARGS(damage, "amount");
+    GDFUNCTION_ARGS(damaged_by, "amount", "source");
+    GDFUNCTION_ARGS(healed_by, "amount", "source");
     GDPROPERTY(injury_max, gd::Variant::INT);
     GDPROPERTY(wounds_max, gd::Variant::INT);
 
@@ -27,8 +30,13 @@ void EntityHealth::_enter_tree() {
     this->emit_signal("damage", this->injury_current, 0, nullptr);
 }
 
+void EntityHealth::damage(int amount) {
+    this->damaged_by(amount, nullptr);
+}
+
 void EntityHealth::damaged_by(int amount, Unit *source) {
     amount = gd::Math::abs(amount);
+    if(this->injury_current <= 0) return; // do not take damage when already dead
     this->injury_current -= amount;
     this->emit_signal("damage", this->injury_current, amount, source);
     this->emit_signal("health_changed", this->injury_current, -amount);

src/goap/action.cpp

@@ -29,6 +29,10 @@ ActionID Action::get_id() const {
     return this->id;
 }
 
+bool Action::get_require_state_complete() const {
+    return this->require_state_complete;
+}
+
 bool Action::procedural_is_possible(ActorWorldState *context) const {
     return true;
 }

src/goap/action.hpp

@@ -43,6 +43,7 @@ public:
     WorldState const &get_effects() const;
 
     ActionID get_id() const;
+    bool get_require_state_complete() const;
 protected:
     Action() = default;
     template<class TState>
@@ -54,6 +55,7 @@ protected:
     WorldState required{};
     WorldState effects{};
     bool only_proc_is_completed{false};
+    bool require_state_complete{true};
 private:
     ActionID id{-1};
 };

src/goap/state.cpp

@@ -16,8 +16,8 @@ void State::_enter_tree() {
 }
 
 void State::_process(double delta_time) {
-    if(this->is_action_done())
+    if(this->is_action_done() && this->get_action()->get_require_state_complete())
-        this->state_finished();
+        this->state_ended();
 }
 
 Action const *State::get_action() const {
@@ -26,20 +26,19 @@ Action const *State::get_action() const {
 
 void State::_end_state() {}
 
-void State::state_finished() {
+void State::state_ended() {
     this->end_state();
-    this->emit_signal("state_finished");
+    this->emit_signal(this->is_action_done() ? "state_finished" : "state_failed");
-}
-
-void State::state_failed() {
-    this->end_state();
-    this->emit_signal("state_failed");
 }
 
 bool State::is_action_done() const {
     return this->action->is_completed(this->world_state);
 }
 
+bool State::is_action_done_interrupt() const {
+    return this->is_action_done() && !this->action->get_require_state_complete();
+}
+
 void State::end_state() {
     this->_end_state();
     this->queue_free();

src/goap/state.hpp

@@ -19,10 +19,12 @@ public:
     virtual void _process(double delta_time) override;
 protected:
     Action const *get_action() const;
+    // \returns True if the Action's requirements are complete. Without evaluating Action::require_state_complete.
     bool is_action_done() const;
+    // \returns True if the Action's requirements are complete. Including Action::require_state_complete.
+    bool is_action_done_interrupt() const;
     virtual void _end_state();
-    void state_finished();
+    void state_ended();
-    void state_failed();
 private:
     void end_state();
 private:

src/register_types.cpp

@@ -35,6 +35,7 @@ void initialize_gdextension_types(ModuleInitializationLevel p_level)
     goap::ActionDB::register_action<FindTarget>();
     goap::ActionDB::register_action<GetInMeleeRange>();
     goap::ActionDB::register_action<MeleeAttack>();
+    goap::ActionDB::register_action<TankSelfHeal>();
 
     ClassDB::register_class<goap::ActorWorldState>();
     ClassDB::register_class<goap::Goal>();

src/rts_actions.cpp

@@ -36,6 +36,7 @@ goap::State *FireAtTarget::get_apply_state(goap::ActorWorldState *context) const
 
 FindTarget::FindTarget()
 : Action() {
+    this->require_state_complete = false;
     this->effects.insert("can_see_target", true);
 }
 
@@ -48,6 +49,7 @@ goap::State *FindTarget::get_apply_state(goap::ActorWorldState *context) const {
 
 GetInMeleeRange::GetInMeleeRange()
 : Action() {
+    this->require_state_complete = false;
     this->effects.insert("is_in_melee_range", true);
     this->required.insert("can_see_target", true);
 }
@@ -71,3 +73,14 @@ goap::State *MeleeAttack::get_apply_state(goap::ActorWorldState *context) const
     state->animation = "melee_attack";
     return state;
 }
+
+TankSelfHeal::TankSelfHeal()
+: Action() {
+    this->effects.insert("is_health_safe", true);
+}
+
+goap::State *TankSelfHeal::get_apply_state(goap::ActorWorldState *context) const {
+    Animate *state{this->create_state<Animate>()};
+    state->animation = "self_heal";
+    return state;
+}

src/rts_actions.hpp

@@ -39,4 +39,11 @@ public:
     virtual goap::State *get_apply_state(goap::ActorWorldState *context) const override;
 };
 
+class TankSelfHeal : public goap::Action {
+    GOAP_ACTION(SelfHeal);
+public:
+    TankSelfHeal();
+    virtual goap::State *get_apply_state(goap::ActorWorldState *context) const override;
+};
+
 #endif // !RTS_ACTIONS_HPP

src/rts_states.cpp

@@ -1,5 +1,8 @@
 #include "rts_states.hpp"
+#include "utils/util_functions.hpp"
+#include <godot_cpp/core/math.hpp>
 #include <godot_cpp/variant/utility_functions.hpp>
+#include <cmath>
 
 void MoveTo::_bind_methods() {}
 
@@ -7,6 +10,7 @@ void MoveTo::_ready() {
     this->agent = this->get_node<gd::NavigationAgent3D>("../NavigationAgent3D");
     this->agent->set_target_position(this->target_node->get_global_position());
     this->parent_node3d = Object::cast_to<gd::Node3D>(this->get_parent());
+    this->calculate_path();
 }
 
 void MoveTo::_end_state() {
@@ -20,10 +24,38 @@ void MoveTo::_process(double delta_time) {
     this->parent_node3d->set_global_position(pos + direction * delta_time);
     this->parent_node3d->look_at(pos - gd::Vector3{direction.x, 0.f, direction.z});
 
-    if(this->is_action_done())
+    bool const navigation_finished{this->agent->is_navigation_finished()};
-        this->state_finished();
+    if(this->is_action_done_interrupt() || navigation_finished)
-    else if(this->agent->is_navigation_finished())
+        this->state_ended();
-        this->state_failed();
+
+    if((utils::time_seconds() - this->last_repath) > this->get_repath_interval())
+        this->calculate_path();
+}
+
+void MoveTo::calculate_path() {
+    gd::Vector3 const target_pos{this->target_node->get_global_position()};
+    this->agent->set_target_position(target_pos);
+    this->last_repath = utils::time_seconds();
+    this->target_position_at_last = target_pos;
+}
+
+float MoveTo::target_delta_position() const {
+    return this->target_position_at_last
+        .distance_to(this->target_node->get_global_position());
+}
+
+float MoveTo::distance_to_target() const {
+    return this->target_position_at_last
+        .distance_to(this->parent_node3d->get_global_position());
+}
+
+double MoveTo::get_repath_interval() const {
+    float const target_delta_position{this->target_delta_position()};
+    if(target_delta_position == 0.f)
+        return INFINITY;
+    else
+        return gd::Math::max(gd::Math::min(double(this->distance_to_target()), 5.0)
+            - target_delta_position, 0.2);
 }
 
 void Activate::_bind_methods() {}
@@ -32,18 +64,15 @@ void Animate::_bind_methods() {}
 
 void Animate::_ready() {
     this->anim = this->get_node<gd::AnimationPlayer>("../AnimationPlayer");
-    this->anim->queue(this->animation);
+    this->anim->play(this->animation);
 }
 
 void Animate::_process(double delta_time) {
-    if(this->is_action_done()) {
+    bool const animation_finished{!this->anim->is_playing() || this->anim->get_current_animation() != this->animation};
-        this->state_finished();
+    if(this->is_action_done_interrupt() || animation_finished)
-    } else if(!this->anim->is_playing() || this->anim->get_current_animation() != this->animation) {
+        this->state_ended();
-        this->state_failed();
-    }
 }
 
 void Animate::_end_state() {
-    if(this->anim->get_current_animation() == this->animation)
     this->anim->stop();
 }

src/rts_states.hpp

@@ -14,11 +14,17 @@ public:
     virtual void _ready() override;
     virtual void _end_state() override;
     virtual void _process(double delta_time) override;
+    void calculate_path();
+    float target_delta_position() const;
+    float distance_to_target() const;
+    double get_repath_interval() const;
 public:
     gd::Node3D *target_node{nullptr};
 private:
     gd::Node3D *parent_node3d{nullptr};
     gd::NavigationAgent3D *agent{nullptr};
+    gd::Vector3 target_position_at_last{};
+    double last_repath{0.0};
 };
 
 class Activate : public goap::State {

src/unit.cpp

@@ -20,8 +20,8 @@ void Unit::_enter_tree() { GDGAMEONLY();
     this->world_state = this->get_node<UnitWorldState>("%ActorWorldState");
     this->world_state->connect("attention_changed", callable_mp(this, &Unit::stop_plan));
     this->anim_player = this->get_node<gd::AnimationPlayer>("%AnimationPlayer");
-    EntityHealth *health{this->get_node<EntityHealth>("%EntityHealth")};
+    this->health = this->get_node<EntityHealth>("%EntityHealth");
-    health->connect("death", callable_mp(this, &Unit::on_death));
+    this->health->connect("death", callable_mp(this, &Unit::on_death));
 }
 
 void Unit::stop_plan() {
@@ -34,9 +34,7 @@ void Unit::stop_plan() {
 }
 
 void Unit::begin_marker_temporary(GoalMarker *marker) {
-    this->destroy_state();
     this->world_state->set_target_node(marker);
-    this->destroy_state();
     this->set_goal_and_plan(marker->get_goal());
     // destroy temporary marker if goal is already achieved or failed
     // connect observers if a plan was formed
@@ -80,6 +78,7 @@ void Unit::aim_at(gd::Node3D *target) {
 }
 
 void Unit::on_death(Unit *damage_source) {
+    this->destroy_state();
     this->anim_player->stop();
     this->anim_player->play("death");
 }
@@ -122,11 +121,16 @@ void Unit::state_finished() {
 }
 
 void Unit::next_action() {
+    // cannot perform actions while dead
+    if(this->health->get_injury_current() <= 0)
+        return;
+    // destroy active state
     if(this->state != nullptr && !this->state->is_queued_for_deletion())
         this->destroy_state();
     this->state = nullptr;
     if(this->current_plan.is_empty())
         return;
+    // pop next action and apply state
     this->state = this->current_plan.get(0)->get_apply_state(this->world_state);
     if(state == nullptr) {
         this->stop_plan();
@@ -135,7 +139,6 @@ void Unit::next_action() {
     }
     this->current_plan.remove_at(0);
     this->add_child(this->state);
-
     this->state->connect("state_finished", this->on_state_finished);
     this->state->connect("state_failed", this->on_plan_failed);
 }

src/unit.hpp

@@ -60,6 +60,7 @@ protected:
     gd::NavigationAgent3D *agent{nullptr};
     gd::AnimationPlayer *anim_player{nullptr};
     goap::Planner *planner{nullptr};
+    EntityHealth *health{nullptr};
     UnitWorldState *world_state{nullptr};
 };
 

src/unit_world_state.cpp

@@ -17,12 +17,14 @@ void UnitWorldState::_bind_methods() {
     GDFUNCTION(get_target_node);
     GDFUNCTION(get_is_target_enemy);
     GDFUNCTION(get_is_in_melee_range);
+    GDFUNCTION(get_is_health_safe);
 }
 
 void UnitWorldState::_enter_tree() { GDGAMEONLY();
     this->parent_unit = gd::Object::cast_to<Unit>(this->get_parent());
     this->agent = this->get_node<gd::NavigationAgent3D>("%NavigationAgent3D");
     this->eye_location = this->get_node<gd::Node3D>("%Eyes");
+    this->health = this->get_node<EntityHealth>("%EntityHealth");
     if(this->parent_unit == nullptr)
         gd::UtilityFunctions::push_warning("UnitWorldState needs to be a child node of a Unit");
 }
@@ -80,6 +82,10 @@ bool UnitWorldState::get_is_in_melee_range() const {
                 .distance_squared_to(this->parent_unit->get_global_position()) <= 4.f;
 }
 
+bool UnitWorldState::get_is_health_safe() const {
+    return float(this->health->get_injury_current()) > (float(this->health->get_injury_max()) / 2.f);
+}
+
 void UnitWorldState::set_target_node(gd::Node3D *node) {
     if(this->target_node != nullptr)
         this->target_node->disconnect("tree_exited", this->target_node_exited_tree.bind(this->target_node));

src/unit_world_state.hpp

@@ -1,6 +1,7 @@
 #ifndef UNIT_WORLD_STATE_HPP
 #define UNIT_WORLD_STATE_HPP
 
+#include "entity_health.hpp"
 #include "goap/actor_world_state.hpp"
 #include <godot_cpp/classes/navigation_agent3d.hpp>
 #include <godot_cpp/classes/node3d.hpp>
@@ -18,6 +19,7 @@ public:
     bool get_is_target_unit() const;
     bool get_is_target_enemy() const;
     bool get_is_in_melee_range() const;
+    bool get_is_health_safe() const;
 
     void set_target_node(gd::Node3D *node);
     gd::Node3D *get_target_node() const;
@@ -27,6 +29,7 @@ private:
     gd::Callable const target_node_exited_tree{callable_mp(this, &UnitWorldState::target_destroyed)};
 protected:
     Unit *parent_unit{nullptr};
+    EntityHealth *health{nullptr};
     gd::NavigationAgent3D *agent{nullptr};
     gd::Node3D *target_node{nullptr};
     gd::Node3D *eye_location{nullptr};