Drying_rate

doc/JSON_INFO.md

@@ -1051,8 +1051,7 @@ reference at least one body part or sub body part.
 | `hit_difficulty`       | (_mandatory_) How hard is it to hit a given body part, assuming "owner" is hit. Higher number means good hits will veer towards this part, lower means this part is unlikely to be hit by inaccurate attacks. Formula is `chance *= pow(hit_roll, hit_difficulty)`
 | `drench_capacity`      | (_mandatory_) How wet this part can get before being 100% drenched. 0 makes the limb waterproof, morale checks for absolute wetness while other effects for wetness percentage - making a high `drench_capacity` prevent the penalties longer.
 | `drench_increment`     | (_optional_) Units of "wetness" applied each time the limb gets drenched. Default 2, ignored by diving underwater.
-| `drying_chance`        | (_optional_) Base chance the bodypart will succeed in the drying roll ( `x/80` chance, modified by ambient temperature etc)
-| `drying_increment`     | (_optonal_) Units of wetness the limb will dry each turn, if it succeeds in the drying roll (base chance `drench_capacity / 80`, modified by ambient temperature).
+| `drying_rate`     | (_optional float_) Divisor on the time needed to dry a given amount of wetness from a bodypart, modified by clothing.  Final drying rate depends on breathability, weather, and `drying_capacity` of the bodypart.
 | `wet_morale`           | (_optional_) Mood bonus/malus when the limb gets wet, representing the morale effect at 100% limb saturation. Modified by worn clothing and ambient temperature.
 | `stylish_bonus`        | (_optional_) Mood bonus associated with wearing fancy clothing on this part. (default: `0`)
 | `hot_morale_mod`       | (_optional_) Mood effect of being too hot on this part. (default: `0`)

src/bodypart.cpp

@@ -312,8 +312,7 @@ void body_part_type::load( const JsonObject &jo, const std::string_view )
 
     mandatory( jo, was_loaded, "drench_capacity", drench_max );
     optional( jo, was_loaded, "drench_increment", drench_increment, 2 );
-    optional( jo, was_loaded, "drying_chance", drying_chance, drench_max );
-    optional( jo, was_loaded, "drying_increment", drying_increment, 1 );
+    optional( jo, was_loaded, "drying_rate", drying_rate, 1.0f );
 
     optional( jo, was_loaded, "wet_morale", wet_morale, 0 );
 

src/bodypart.h

@@ -312,8 +312,7 @@ struct body_part_type {
         units::temperature_delta temp_max = 0_C_delta;
         int drench_max = 0;
         int drench_increment = 2;
-        int drying_chance = 1;
-        int drying_increment = 1;
+        float drying_rate = 1.0f;
         // Wetness morale bonus/malus of the limb
         int wet_morale = 0;
         int technique_enc_limit = 50;

src/character_body.cpp

@@ -135,11 +135,10 @@ void Character::update_body_wetness( const w_point &weather )
 
             // Make clothing slow down drying
             const float clothing_mult = worn.clothing_wetness_mult( bp );
-
-            const time_duration drying = bp->drying_increment * average_drying * trait_mult * weather_mult *
+            const float drying_rate = bp->drying_rate;
+            const time_duration drying = average_drying * trait_mult * weather_mult *
                                          temp_mult / clothing_mult;
-            const float turns_to_dry = to_turns<float>( drying );
-
+            const float turns_to_dry = to_turns<float>( drying ) / drying_rate;
             const int drench_cap = get_part_drench_capacity( bp );
             const float dry_per_turn = static_cast<float>( drench_cap ) / turns_to_dry;
             mod_part_wetness( bp, roll_remainder( dry_per_turn ) * -1 );

tests/limb_test.cpp

@@ -144,6 +144,51 @@ TEST_CASE( "Healing/mending_bonuses", "[character][limb]" )
     }
 }
 
+TEST_CASE( "drying_rate", "[character][limb]" )
+{
+    standard_npc dude( "Test NPC" );
+    clear_character( dude, true );
+    const weather_manager weather = get_weather();
+    REQUIRE( body_part_arm_l->drying_rate == 1.0f );
+    dude.drench( 100, dude.get_drenching_body_parts(), false );
+    REQUIRE( dude.get_part_wetness( body_part_arm_l ) == 200 );
+
+    // Baseline arm dries in 450ish turns
+    int base_dry = 0;
+    while( dude.get_part_wetness( body_part_arm_l ) > 0 ) {
+        dude.update_body_wetness( *weather.weather_precise );
+        base_dry++;
+    }
+    REQUIRE( base_dry == Approx( 450 ).margin( 100 ) );
+
+    // Birdify, clear water
+    clear_character( dude, true );
+    create_bird_char( dude );
+    REQUIRE( body_part_test_bird_wing_l->drying_rate == 2.0f );
+    REQUIRE( body_part_test_bird_wing_r->drying_rate == 0.5f );
+    REQUIRE( dude.get_part_wetness( body_part_test_bird_wing_l ) == 0 );
+    REQUIRE( dude.get_part_wetness( body_part_test_bird_wing_r ) == 0 );
+    dude.drench( 100, dude.get_drenching_body_parts(), false );
+    REQUIRE( dude.get_part_wetness( body_part_test_bird_wing_l ) == 200 );
+    REQUIRE( dude.get_part_wetness( body_part_test_bird_wing_r ) == 200 );
+
+    int high_dry = 0;
+    int low_dry = 0;
+    // Filter on the slower drying limb
+    while( dude.get_part_wetness( body_part_test_bird_wing_r ) > 0 ) {
+        dude.update_body_wetness( *weather.weather_precise );
+        if( dude.get_part_wetness( body_part_test_bird_wing_l ) > 0 ) {
+            high_dry++;
+        }
+        low_dry++;
+    }
+
+    // A drying rate of 2 should halve the drying time
+    // Higher margin for the lower rate to account for the randomness
+    CHECK( high_dry == Approx( base_dry / 2 ).margin( base_dry / 4 ) );
+    CHECK( low_dry == Approx( base_dry * 2 ).margin( base_dry ) );
+}
+
 TEST_CASE( "Limb_armor_coverage", "[character][limb][armor]" )
 {
     standard_npc dude( "Test NPC" );