Add lighting system

src/components.rs

@@ -285,6 +285,12 @@ pub struct OtherLevelPosition {
     pub depth: i32,
 }
 
+#[derive(Component, Serialize, Deserialize, Clone)]
+pub struct LightSource {
+    pub color: RGB,
+    pub range: i32,
+}
+
 // Serialization helper code. We need to implement ConvertSaveLoad for each type that contains an
 // Entity.
 

src/lighting_system.rs

@@ -0,0 +1,45 @@
+use ::rltk::{Point, RGB};
+use ::specs::prelude::*;
+use rltk::DistanceAlg;
+
+use super::{LightSource, Map, Position, Viewshed};
+
+pub struct LightingSystem {}
+
+impl<'a> System<'a> for LightingSystem {
+    #[allow(clippy::type_complexity)]
+    type SystemData = (
+        WriteExpect<'a, Map>,
+        ReadStorage<'a, Viewshed>,
+        ReadStorage<'a, Position>,
+        ReadStorage<'a, LightSource>,
+    );
+
+    fn run(&mut self, data: Self::SystemData) {
+        let (mut map, viewshed, positions, lighting) = data;
+
+        if map.outdoors {
+            return;
+        }
+
+        let black = RGB::from_f32(0., 0., 0.);
+        for l in map.light.iter_mut() {
+            *l = black;
+        }
+
+        for (viewshed, pos, light) in (&viewshed, &positions, &lighting).join() {
+            let light_point = Point::from(*pos);
+            let range_f = light.range as f32;
+
+            for t in viewshed.visible_tiles.iter() {
+                if t.x > 0 && t.x < map.width && t.y > 0 && t.y < map.height {
+                    let idx = map.xy_idx(t.x, t.y);
+                    let distance = DistanceAlg::Pythagoras.distance2d(light_point, *t);
+                    let intensity = (range_f - distance) / range_f;
+
+                    map.light[idx] = map.light[idx] + (light.color * intensity);
+                }
+            }
+        }
+    }
+}

src/main.rs

@@ -8,6 +8,7 @@ mod gamesystem;
 mod gui;
 mod hunger_system;
 mod inventory_system;
+mod lighting_system;
 mod map;
 pub mod map_builders;
 mod map_indexing_system;
@@ -38,6 +39,7 @@ pub use game_log::GameLog;
 use gui::{show_cheat_mode, CheatMenuResult};
 use hunger_system::HungerSystem;
 use inventory_system::{ItemCollectionSystem, ItemDropSystem, ItemRemoveSystem, ItemUseSystem};
+use lighting_system::LightingSystem;
 pub use map::*;
 use map_indexing_system::MapIndexingSystem;
 use melee_combat_system::MeleeCombatSystem;
@@ -152,6 +154,9 @@ impl State {
         let mut particles = ParticleSpawnSystem {};
         particles.run_now(&self.ecs);
 
+        let mut lighting = LightingSystem {};
+        lighting.run_now(&self.ecs);
+
         self.ecs.maintain();
     }
 }
@@ -468,6 +473,7 @@ fn main() -> ::rltk::BError {
         InBackpack,
         InflictsDamage,
         Item,
+        LightSource,
         LootTable,
         MagicMapper,
         MeleeWeapon,

src/map.rs

@@ -8,6 +8,7 @@ use ::rltk::{Algorithm2D, BaseMap, Point, SmallVec};
 use ::serde::{Deserialize, Serialize};
 use ::specs::prelude::*;
 pub use dungeon::*;
+use rltk::RGB;
 pub use themes::*;
 pub use tiletype::{tile_opaque, tile_walkable, TileType};
 
@@ -25,6 +26,8 @@ pub struct Map {
     pub bloodstains: HashSet<usize>,
     pub view_blocked: HashSet<usize>,
     pub name: String,
+    pub outdoors: bool,
+    pub light: Vec<RGB>,
 
     #[serde(skip_serializing)]
     #[serde(skip_deserializing)]
@@ -74,6 +77,8 @@ impl Map {
             bloodstains: HashSet::new(),
             view_blocked: HashSet::new(),
             name: name.to_string(),
+            outdoors: true,
+            light: vec![RGB::from_f32(0., 0., 0.); map_tile_count],
         }
     }
 }

src/map/themes.rs

@@ -16,6 +16,9 @@ pub fn tile_glyph(idx: usize, map: &Map) -> (FontCharType, RGB, RGB) {
     if !map.visible_tiles[idx] {
         fg = fg.to_greyscale();
         bg = RGB::from_f32(0., 0., 0.);
+    } else if !map.outdoors {
+        fg = fg * map.light[idx];
+        bg = bg * map.light[idx];
     }
 
     (glyph, fg, bg)

src/map_builders/limestone_cavern.rs

@@ -4,7 +4,7 @@ use super::{
     AreaStartingPosition, BuilderChain, BuilderMap, CullUnreachable, DistantExit,
     DrunkardsWalkBuilder, MetaMapBuilder, VoronoiSpawning, XStart, YStart,
 };
-use crate::map::{self, TileType};
+use crate::map::TileType;
 
 pub fn limestone_cavern_builder(
     new_depth: i32,
@@ -82,5 +82,6 @@ impl CaveDecorator {
         }
 
         build_data.take_snapshot();
+        build_data.map.outdoors = false;
     }
 }

src/saveload_system.rs

@@ -80,6 +80,7 @@ pub fn save_game(ecs: &mut World) {
             InBackpack,
             InflictsDamage,
             Item,
+            LightSource,
             LootTable,
             MagicMapper,
             MeleeWeapon,
@@ -184,6 +185,7 @@ pub fn load_game(ecs: &mut World) {
             InBackpack,
             InflictsDamage,
             Item,
+            LightSource,
             LootTable,
             MagicMapper,
             MeleeWeapon,

src/spawner.rs

@@ -50,6 +50,10 @@ pub fn player(ecs: &mut World, player_x: i32, player_y: i32) -> Entity {
             xp: 0,
             level: 1,
         })
+        .with(LightSource {
+            color: RGB::from_f32(1.0, 1.0, 0.5),
+            range: 8,
+        })
         .marked::<SimpleMarker<SerializeMe>>()
         .build();