Sound-triggered traps (#68047)

* Sound-triggered traps. Add traps to sound processing, add sound_threshold json key for traps, and add a test noise-triggered trap.

* Lint data/json/traps.json

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* Update src/sounds.cpp

Co-authored-by: ehughsbaird <44244083+ehughsbaird@users.noreply.github.com>

* Update src/trap.h

Co-authored-by: ehughsbaird <44244083+ehughsbaird@users.noreply.github.com>

* Add doc for new json key

* Match func def to updated func dec

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: ehughsbaird <44244083+ehughsbaird@users.noreply.github.com>

data/json/traps.json

@@ -1155,5 +1155,17 @@
     "name": "portal dungeon next level",
     "copy-from": "trap_base",
     "effect_str": "EOC_PORTAL_STORM_DUNGEON_NEXT_LEVEL"
+  },
+  {
+    "type": "trap",
+    "id": "tr_noisetest",
+    "name": "noise test trap",
+    "color": "light_cyan",
+    "symbol": "_",
+    "visibility": 0,
+    "avoidance": 8,
+    "difficulty": 0,
+    "action": "sound_detect",
+    "sound_threshold": 5
   }
 ]

doc/JSON_INFO.md

@@ -2773,7 +2773,8 @@ See [MUTATIONS.md](MUTATIONS.md)
       "spawn_items": [ "beartrap" ]
     },
     "trigger_message_u": "A bear trap closes on your foot!", // This message will be printed when player steps on a trap
-    "trigger_message_npc": "A bear trap closes on <npcname>'s foot!" // This message will be printed when NPC or monster steps on a trap
+    "trigger_message_npc": "A bear trap closes on <npcname>'s foot!", // This message will be printed when NPC or monster steps on a trap
+    "sound_threshold": 5 // Optional. Minimum volume of sound that will trigger this trap. Defaults to 0 (Will not trigger from sound).
 ```
 
 ### Vehicle Groups

src/sounds.cpp

@@ -37,6 +37,7 @@
 #include "safemode_ui.h"
 #include "string_formatter.h"
 #include "translations.h"
+#include "trap.h"
 #include "type_id.h"
 #include "uistate.h"
 #include "units.h"
@@ -481,6 +482,16 @@ void sounds::process_sounds()
                 critter.hear_sound( source, vol, dist, this_centroid.provocative );
             }
         }
+        // Trigger sound-triggered traps
+        for( const trap *trapType : trap::get_sound_triggered_traps() ) {
+            for( const tripoint &tp : get_map().trap_locations( trapType->id ) ) {
+                const int dist = sound_distance( source, tp );
+                const trap &tr = get_map().tr_at( tp );
+                if( tr.triggered_by_sound( vol, dist ) ) {
+                    tr.trigger( tp );
+                }
+            }
+        }
     }
     recent_sounds.clear();
 }

src/trap.cpp

@@ -115,6 +115,13 @@ const std::vector<const trap *> &trap::get_funnels()
     return funnel_traps;
 }
 
+static std::vector<const trap *> sound_triggered_traps;
+
+const std::vector<const trap *> &trap::get_sound_triggered_traps()
+{
+    return sound_triggered_traps;
+}
+
 size_t trap::count()
 {
     return trap_factory.size();
@@ -164,6 +171,7 @@ void trap::load( const JsonObject &jo, const std::string_view )
     optional( jo, was_loaded, "floor_bedding_warmth", floor_bedding_warmth, 0 );
     optional( jo, was_loaded, "spell_data", spell_data );
     assign( jo, "trigger_weight", trigger_weight );
+    optional( jo, was_loaded, "sound_threshold", sound_threshold );
     for( const JsonValue entry : jo.get_array( "drops" ) ) {
         itype_id item_type;
         int quantity = 0;
@@ -226,6 +234,7 @@ update_mapgen_id trap::map_regen_target() const
 void trap::reset()
 {
     funnel_traps.clear();
+    sound_triggered_traps.clear();
     trap_factory.reset();
 }
 
@@ -307,6 +316,14 @@ bool trap::can_see( const tripoint &pos, const Character &p ) const
     return visibility < 0 || p.knows_trap( pos );
 }
 
+void trap::trigger( const tripoint &pos ) const
+{
+    if( is_null() ) {
+        return;
+    }
+    act( pos, nullptr, nullptr );
+}
+
 void trap::trigger( const tripoint &pos, Creature &creature ) const
 {
     return trigger( pos, &creature, nullptr );
@@ -348,6 +365,17 @@ bool trap::is_funnel() const
     return !is_null() && funnel_radius_mm > 0;
 }
 
+bool trap::has_sound_trigger() const
+{
+    return !is_null() && sound_threshold > 0;
+}
+
+bool trap::triggered_by_sound( int vol, int dist ) const
+{
+    const int volume = vol - dist;
+    return !is_null() && volume >= sound_threshold;
+}
+
 void trap::on_disarmed( map &m, const tripoint &p ) const
 {
     for( const auto &i : components ) {
@@ -396,6 +424,9 @@ void trap::finalize()
         if( t.is_funnel() ) {
             funnel_traps.push_back( &t );
         }
+        if( t.has_sound_trigger() ) {
+            sound_triggered_traps.push_back( &t );
+        }
     }
 
     tr_null = trap_str_id::NULL_ID().id();

src/trap.h

@@ -65,6 +65,7 @@ bool map_regen( const tripoint &p, Creature *c, item *i );
 bool drain( const tripoint &p, Creature *c, item *i );
 bool snake( const tripoint &p, Creature *c, item *i );
 bool cast_spell( const tripoint &p, Creature *critter, item * );
+bool sound_detect( const tripoint &p, Creature *, item * );
 } // namespace trapfunc
 
 struct vehicle_handle_trap_data {
@@ -151,6 +152,10 @@ struct trap {
          * If an item with this weight or more is thrown onto the trap, it triggers.
          */
         units::mass trigger_weight = 500_gram;
+        /**
+         * If a sound of at least this volume reaches the trap, it triggers.
+         */
+        int sound_threshold = 0;
         int funnel_radius_mm = 0;
         // For disassembly?
         std::vector<std::tuple<itype_id, int, int>> components;
@@ -284,6 +289,8 @@ struct trap {
         void trigger( const tripoint &pos, item &item ) const;
         /*@}*/
 
+        void trigger( const tripoint &pos ) const;
+
         /**
          * If the given item is throw onto the trap, does it trigger the trap?
          */
@@ -331,6 +338,13 @@ struct trap {
         static const std::vector<const trap *> &get_funnels();
         /*@}*/
 
+        /*
+         * Can the trap be triggered by sounds?
+         */
+        bool has_sound_trigger() const;
+        static const std::vector<const trap *> &get_sound_triggered_traps();
+        bool triggered_by_sound( int vol, int dist ) const;
+
         /*@{*/
         /**
          * @name Initialization

src/trapfunc.cpp

@@ -1575,6 +1575,16 @@ bool trapfunc::snake( const tripoint &p, Creature *, item * )
     return true;
 }
 
+/**
+ * Made to test sound-triggered traps.
+ * Warning: generating a sound can trigger sound-triggered traps.
+ */
+bool trapfunc::sound_detect( const tripoint &p, Creature *, item * )
+{
+    sounds::sound( p, 10, sounds::sound_t::alert, _( "Sound Detected!" ), false, "misc" );
+    return true;
+}
+
 /**
  * Takes the name of a trap function and returns a function pointer to it.
  * @param function_name The name of the trapfunc function to find.
@@ -1618,7 +1628,8 @@ const trap_function &trap_function_from_string( const std::string &function_name
             { "map_regen", trapfunc::map_regen },
             { "drain", trapfunc::drain },
             { "spell", trapfunc::cast_spell },
-            { "snake", trapfunc::snake }
+            { "snake", trapfunc::snake },
+            { "sound_detect", trapfunc::sound_detect }
         }
     };