add entity events: on_aim_on, on_aim_off

src/logic/PlayerController.cpp

@@ -357,6 +357,7 @@ voxel* PlayerController::updateSelection(float maxDistance) {
     if (vox) {
         maxDistance = glm::distance(camera->position, end);
     }
+    auto prevEntity = selection.entity;
     selection.entity = ENTITY_NONE;
     selection.actualPosition = iend;
     if (auto result = level->entities->rayCast(
@@ -367,6 +368,18 @@ voxel* PlayerController::updateSelection(float maxDistance) {
         selection.actualPosition = selection.position;
         selection.normal = result->normal;
     }
+    if (selection.entity != prevEntity) {
+        if (prevEntity != ENTITY_NONE) {
+            if (auto pentity = level->entities->get(prevEntity)) {
+                scripting::on_aim_off(*pentity, player.get());
+            }
+        }
+        if (selection.entity != ENTITY_NONE) {
+            if (auto pentity = level->entities->get(selection.entity)) {
+                scripting::on_aim_on(*pentity, player.get());
+            }
+        }
+    }
     if (vox == nullptr || selection.entity) {
         selection.vox = {BLOCK_VOID, {}};
         return nullptr;

src/logic/scripting/scripting.cpp

@@ -346,6 +346,8 @@ void scripting::on_entity_spawn(
         funcsset.on_sensor_enter = lua::hasfield(L, "on_sensor_enter");
         funcsset.on_sensor_exit = lua::hasfield(L, "on_sensor_exit");
         funcsset.on_save = lua::hasfield(L, "on_save");
+        funcsset.on_aim_on = lua::hasfield(L, "on_aim_on");
+        funcsset.on_aim_off = lua::hasfield(L, "on_aim_off");
         lua::pop(L, 2);
 
         component->env = compenv;
@@ -423,6 +425,20 @@ void scripting::on_sensor_exit(const Entity& entity, size_t index, entityid_t oi
     });
 }
 
+void scripting::on_aim_on(const Entity& entity, Player* player) {
+    process_entity_callback(entity, "on_aim_on", 
+            &entity_funcs_set::on_aim_on, [player](auto L) {
+        return lua::pushinteger(L, player->getId());
+    });
+}
+
+void scripting::on_aim_off(const Entity& entity, Player* player) {
+    process_entity_callback(entity, "on_aim_off", 
+            &entity_funcs_set::on_aim_off, [player](auto L) {
+        return lua::pushinteger(L, player->getId());
+    });
+}
+
 void scripting::on_entities_update() {
     auto L = lua::get_main_thread();
     lua::get_from(L, STDCOMP, "update", true);

src/logic/scripting/scripting.hpp

@@ -93,6 +93,8 @@ namespace scripting {
     void on_entities_render();
     void on_sensor_enter(const Entity& entity, size_t index, entityid_t oid);
     void on_sensor_exit(const Entity& entity, size_t index, entityid_t oid);
+    void on_aim_on(const Entity& entity, Player* player);
+    void on_aim_off(const Entity& entity, Player* player);
 
     /// @brief Called on UI view show
     void on_ui_open(