From bbe71bb37837819109366fcc372a91754099e49b Mon Sep 17 00:00:00 2001 From: Serhii Snitsaruk Date: Tue, 30 Jul 2024 12:31:25 +0200 Subject: [PATCH] Add transition guards --- hsm/limbo_hsm.cpp | 17 +++++++++++------ hsm/limbo_hsm.h | 5 ++++- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/hsm/limbo_hsm.cpp b/hsm/limbo_hsm.cpp index 52730d2..abc3182 100644 --- a/hsm/limbo_hsm.cpp +++ b/hsm/limbo_hsm.cpp @@ -100,7 +100,7 @@ void LimboHSM::update(double p_delta) { } } -void LimboHSM::add_transition(LimboState *p_from_state, LimboState *p_to_state, const StringName &p_event) { +void LimboHSM::add_transition(LimboState *p_from_state, LimboState *p_to_state, const StringName &p_event, const Callable &p_guard) { ERR_FAIL_COND_MSG(p_from_state != nullptr && p_from_state->get_parent() != this, "LimboHSM: Unable to add a transition from a state that is not an immediate child of mine."); ERR_FAIL_COND_MSG(p_to_state == nullptr, "LimboHSM: Unable to add a transition to a null state."); ERR_FAIL_COND_MSG(p_to_state->get_parent() != this, "LimboHSM: Unable to add a transition to a state that is not an immediate child of mine."); @@ -108,8 +108,13 @@ void LimboHSM::add_transition(LimboState *p_from_state, LimboState *p_to_state, TransitionKey key = Transition::make_key(p_from_state, p_event); ERR_FAIL_COND_MSG(transitions.has(key), "LimboHSM: Unable to add another transition with the same event and origin."); - // Note: Explicit casting needed for GDExtension. - transitions[key] = { p_from_state != nullptr ? ObjectID(p_from_state->get_instance_id()) : ObjectID(), ObjectID(p_to_state->get_instance_id()), p_event }; + // Note: Explicit ObjectID casting needed for GDExtension. + transitions[key] = { + p_from_state != nullptr ? ObjectID(p_from_state->get_instance_id()) : ObjectID(), + ObjectID(p_to_state->get_instance_id()), + p_event, + p_guard + }; } void LimboHSM::remove_transition(LimboState *p_from_state, const StringName &p_event) { @@ -166,13 +171,13 @@ bool LimboHSM::_dispatch(const StringName &p_event, const Variant &p_cargo) { Transition transition; _get_transition(active_state, p_event, transition); - if (transition.is_valid()) { + if (transition.is_valid() && transition.is_allowed()) { to_state = Object::cast_to(ObjectDB::get_instance(transition.to_state)); } if (to_state == nullptr) { // Get ANYSTATE transition. _get_transition(nullptr, p_event, transition); - if (transition.is_valid()) { + if (transition.is_valid() && transition.is_allowed()) { to_state = Object::cast_to(ObjectDB::get_instance(transition.to_state)); if (to_state == active_state) { // Transitions to self are not allowed with ANYSTATE. @@ -300,7 +305,7 @@ void LimboHSM::_bind_methods() { ClassDB::bind_method(D_METHOD("get_leaf_state"), &LimboHSM::get_leaf_state); ClassDB::bind_method(D_METHOD("set_active", "active"), &LimboHSM::set_active); ClassDB::bind_method(D_METHOD("update", "delta"), &LimboHSM::update); - ClassDB::bind_method(D_METHOD("add_transition", "from_state", "to_state", "event"), &LimboHSM::add_transition); + ClassDB::bind_method(D_METHOD("add_transition", "from_state", "to_state", "event", "guard"), &LimboHSM::add_transition, DEFVAL(Callable())); ClassDB::bind_method(D_METHOD("remove_transition", "from_state", "event"), &LimboHSM::remove_transition); ClassDB::bind_method(D_METHOD("has_transition", "from_state", "event"), &LimboHSM::has_transition); ClassDB::bind_method(D_METHOD("anystate"), &LimboHSM::anystate); diff --git a/hsm/limbo_hsm.h b/hsm/limbo_hsm.h index f7890c1..4f446f3 100644 --- a/hsm/limbo_hsm.h +++ b/hsm/limbo_hsm.h @@ -39,9 +39,12 @@ private: ObjectID from_state; ObjectID to_state; StringName event; + Callable guard; inline bool is_valid() const { return to_state != ObjectID(); } + inline bool is_allowed() const { return guard.is_null() || guard.call(); } + static _FORCE_INLINE_ TransitionKey make_key(LimboState *p_from_state, const StringName &p_event) { return TransitionKey( p_from_state != nullptr ? uint64_t(p_from_state->get_instance_id()) : 0, @@ -93,7 +96,7 @@ public: void update(double p_delta); - void add_transition(LimboState *p_from_state, LimboState *p_to_state, const StringName &p_event); + void add_transition(LimboState *p_from_state, LimboState *p_to_state, const StringName &p_event, const Callable &p_guard = Callable()); void remove_transition(LimboState *p_from_state, const StringName &p_event); bool has_transition(LimboState *p_from_state, const StringName &p_event) const { return transitions.has(Transition::make_key(p_from_state, p_event)); }