Add Fireball scroll

src/components.rs

@@ -128,3 +128,8 @@ pub struct Ranged {
 pub struct InflictsDamage {
     pub damage: i32,
 }
+
+#[derive(Component, Debug)]
+pub struct AreaOfEffect {
+    pub radius: i32,
+}

src/inventory_system.rs

@@ -1,6 +1,7 @@
 use crate::{
-    game_log::GameLog, CombatStats, Consumable, InBackpack, InflictsDamage, Map, Name, Position,
-    ProvidesHealing, SufferDamage, WantsToDropItem, WantsToPickupItem, WantsToUseItem,
+    game_log::GameLog, AreaOfEffect, CombatStats, Consumable, InBackpack, InflictsDamage, Map,
+    Name, Position, ProvidesHealing, SufferDamage, WantsToDropItem, WantsToPickupItem,
+    WantsToUseItem,
 };
 use specs::prelude::*;
 
@@ -60,6 +61,7 @@ impl<'a> System<'a> for ItemUseSystem {
         ReadStorage<'a, InflictsDamage>,
         WriteStorage<'a, CombatStats>,
         WriteStorage<'a, SufferDamage>,
+        ReadStorage<'a, AreaOfEffect>,
     );
 
     fn run(&mut self, data: Self::SystemData) {
@@ -75,27 +77,67 @@ impl<'a> System<'a> for ItemUseSystem {
             inflict_damage,
             mut combat_stats,
             mut suffer_damage,
+            aoe,
         ) = data;
 
-        for (entity, useitem, stats) in (&entities, &wants_use, &mut combat_stats).join() {
+        for (entity, useitem) in (&entities, &wants_use).join() {
             let mut used_item = true;
 
+            // Targeting
+            let mut targets: Vec<Entity> = Vec::new();
+            match useitem.target {
+                None => {
+                    targets.push(*player_entity);
+                }
+                Some(target) => {
+                    match aoe.get(useitem.item) {
+                        None => {
+                            // Single target in tile
+                            let idx = map.xy_idx(target.x, target.y);
+                            for mob in map.tile_content[idx].iter() {
+                                targets.push(*mob);
+                            }
+                        }
+                        Some(area_effect) => {
+                            // AoE
+                            let mut blast_tiles =
+                                rltk::field_of_view(target, area_effect.radius, &*map);
+                            blast_tiles.retain(|p| {
+                                p.x > 0 && p.x < map.width - 1 && p.y > 0 && p.y < map.height - 1
+                            });
+
+                            for tile_idx in blast_tiles.iter() {
+                                let idx = map.xy_idx(tile_idx.x, tile_idx.y);
+                                for mob in map.tile_content[idx].iter() {
+                                    targets.push(*mob);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+
             // If the item heals, apply the healing
             match healing.get(useitem.item) {
                 None => {}
                 Some(healer) => {
                     used_item = false;
 
-                    stats.hp = i32::min(stats.max_hp, stats.hp + healer.heal_amount);
-                    if entity == *player_entity {
-                        gamelog.entries.push(format!(
-                            "You drink the {}, healing {} hp.",
-                            names.get(useitem.item).unwrap().name,
-                            healer.heal_amount
-                        ));
-                    }
+                    for target in targets.iter() {
+                        let stats = combat_stats.get_mut(*target);
+                        if let Some(stats) = stats {
+                            stats.hp = i32::min(stats.max_hp, stats.hp + healer.heal_amount);
+                            if entity == *player_entity {
+                                gamelog.entries.push(format!(
+                                    "You drink the {}, healing {} hp.",
+                                    names.get(useitem.item).unwrap().name,
+                                    healer.heal_amount
+                                ));
+                            }
 
-                    used_item = true;
+                            used_item = true;
+                        }
+                    }
                 }
             }
 
@@ -103,11 +145,9 @@ impl<'a> System<'a> for ItemUseSystem {
             match inflict_damage.get(useitem.item) {
                 None => {}
                 Some(damage) => {
-                    let target_point = useitem.target.unwrap();
-                    let idx = map.xy_idx(target_point.x, target_point.y);
                     used_item = false;
 
-                    for mob in map.tile_content[idx].iter() {
+                    for mob in targets.iter() {
                         SufferDamage::new_damage(&mut suffer_damage, *mob, damage.damage);
                         if entity == *player_entity {
                             let mob_name = names.get(*mob).unwrap();

src/main.rs

@@ -253,6 +253,7 @@ fn main() -> rltk::BError {
         Consumable,
         Ranged,
         InflictsDamage,
+        AreaOfEffect,
     );
 
     let map = Map::new_map_rooms_and_corridors();

src/spawner.rs

@@ -1,6 +1,6 @@
 use crate::{
-    BlocksTile, CombatStats, Consumable, InflictsDamage, Item, Monster, Name, Player, Position,
-    ProvidesHealing, Ranged, Rect, Renderable, Viewshed, MAP_WIDTH,
+    AreaOfEffect, BlocksTile, CombatStats, Consumable, InflictsDamage, Item, Monster, Name, Player,
+    Position, ProvidesHealing, Ranged, Rect, Renderable, Viewshed, MAP_WIDTH,
 };
 use rltk::{RandomNumberGenerator, RGB};
 use specs::prelude::*;
@@ -172,11 +172,30 @@ fn random_item(ecs: &mut World, x: i32, y: i32) {
     let roll: i32;
     {
         let mut rng = ecs.write_resource::<RandomNumberGenerator>();
-        roll = rng.roll_dice(1, 2);
+        roll = rng.roll_dice(1, 3);
     }
 
     match roll {
         1 => health_potion(ecs, x, y),
+        2 => fireball_scroll(ecs, x, y),
         _ => magic_missile_scroll(ecs, x, y),
     }
 }
+
+fn fireball_scroll(ecs: &mut World, x: i32, y: i32) {
+    ecs.create_entity()
+        .with(Position { x, y })
+        .with(Renderable {
+            glyph: rltk::to_cp437(')'),
+            fg: RGB::named(rltk::ORANGE),
+            bg: RGB::named(rltk::BLACK),
+            render_order: 2,
+        })
+        .with(Name::new("Fireball Scroll"))
+        .with(Item {})
+        .with(Consumable {})
+        .with(Ranged { range: 6 })
+        .with(InflictsDamage { damage: 20 })
+        .with(AreaOfEffect { radius: 3 })
+        .build();
+}