heart containers

kiln-core/src/action.rs

@@ -79,6 +79,9 @@ pub(crate) enum Action {
     /// Add `n` to the player's gem count (negative subtracts; the count is
     /// clamped at 0). Zero time cost. Applied to `GameState::player_gems`.
     AddGems(i64),
+    /// Add `dh` to the player's health (clamped to `[0, max_health]`). Zero time
+    /// cost. Applied to `GameState::player_health`.
+    AlterHealth(i64),
     /// Give (`true`) or take (`false`) the named key color from the player.
     ///
     /// Color must be one of `"blue"`, `"green"`, `"cyan"`, `"red"`, `"purple"`,
@@ -197,6 +200,10 @@ pub(crate) fn action_to_map(action: &Action) -> rhai::Map {
             m.insert("type".into(), ds("AddGems"));
             m.insert("n".into(), Dynamic::from(*n));
         }
+        Action::AlterHealth(dh) => {
+            m.insert("type".into(), ds("AlterHealth"));
+            m.insert("dh".into(), Dynamic::from(*dh));
+        }
         Action::SetKey(color, present) => {
             m.insert("type".into(), ds("SetKey"));
             m.insert("color".into(), Dynamic::from(color.clone()));

kiln-core/src/archetype.rs

@@ -103,6 +103,10 @@ builtins! {
         behavior: Behavior { solid: true, opaque: false, pushable: Pushable::Any, grab: true },
         script: include_str!("scripts/gem.rhai"),
     },
+    Heart => ["heart" => g(3, 0xCC, 0x22, 0x22)] {
+        behavior: Behavior { solid: true, opaque: false, pushable: Pushable::Any, grab: true },
+        script: include_str!("scripts/heart.rhai"),
+    },
     Pusher => [
         "pusher_north" => g(30, 0xAA, 0xAA, 0xAA),
         "pusher_south" => g(31, 0xAA, 0xAA, 0xAA),

kiln-core/src/cp437.rs

@@ -17,7 +17,7 @@
 /// space since a literal NUL is not displayable.
 const CP437: [char; 256] = [
     // 0x00–0x0F
-    ' ', '☺', '☻', '♥', '♦', '♣', '♠', '•', '◘', '○', '◙', '♂', '♀', '♪', '♫', '☼',
+    ' ', '☺', '☻', '♡', '♦', '♣', '♠', '•', '◘', '○', '◙', '♂', '♀', '♪', '♫', '☼',
     // 0x10–0x1F
     '►', '◄', '↕', '‼', '¶', '§', '▬', '↨', '↑', '↓', '→', '←', '∟', '↔', '▲', '▼',
     // 0x20–0x2F  (ASCII space onward)

kiln-core/src/game.rs

@@ -152,12 +152,14 @@ pub struct GameState {
     /// may block input or show a visual effect while it is `Some(t)` where `t > 0`.
     pub board_transition: Option<f64>,
     /// The player's current health. Game-global (not per-board), so it persists
-    /// across board transitions. Players start with `5`. There is no runtime
-    /// mutation path yet — front-ends only display it.
+    /// across board transitions. Scripts change it via `alter_health(dh)`, which
+    /// clamps to `[0, max_health]`. Front-ends display it via the status sidebar.
     pub player_health: u32,
+    /// The maximum health the player can have. Scripts clamp `alter_health` to
+    /// this ceiling; the status sidebar uses it to size the heart row.
+    pub max_health: u32,
     /// The number of gems the player has collected. Game-global like
-    /// [`player_health`](GameState::player_health); starts at `0` and is
-    /// display-only for now.
+    /// [`player_health`](GameState::player_health); starts at `0`.
     pub player_gems: u32,
     /// The player's key inventory. Game-global; persists across board transitions.
     pub player_keys: Keyring,
@@ -188,6 +190,7 @@ impl GameState {
             active_scroll: None,
             board_transition: None,
             player_health: 5,
+            max_health: 5,
             player_gems: 0,
             player_keys: Keyring::default(),
         };
@@ -298,9 +301,10 @@ impl GameState {
         // below also borrows `self`.
         let mut logs: Vec<LogLine> = Vec::new();
         let mut bumps: Vec<(ObjectId, i64)> = Vec::new();
-        // Net change to the player's gem count from AddGems actions; applied to
-        // `self` after the board borrow drops.
+        // Net change to player stats from AddGems / AlterHealth actions; applied
+        // to `self` after the board borrow drops.
         let mut gem_delta: i64 = 0;
+        let mut health_delta: i64 = 0;
         let mut key_changes: Vec<(String, bool)> = Vec::new();
         let mut sends: Vec<(ObjectId, String, Option<ScriptArg>)> = Vec::new();
         let mut new_bubbles: Vec<SpeechBubble> = Vec::new();
@@ -403,6 +407,8 @@ impl GameState {
                     }
                     // Accumulated and applied to `self.player_gems` after the borrow drops.
                     Action::AddGems(n) => gem_delta += n,
+                    // Accumulated and applied to `self.player_health` after the borrow drops.
+                    Action::AlterHealth(dh) => health_delta += dh,
                     // Collected and applied to `self.player_keys` after the borrow drops.
                     Action::SetKey(color, present) => key_changes.push((color, present)),
                     // A grab thing despawns itself from its grab() hook.
@@ -426,6 +432,11 @@ impl GameState {
         if gem_delta != 0 {
             self.player_gems = (self.player_gems as i64 + gem_delta).max(0) as u32;
         }
+        // Apply the net health change (clamped to [0, max_health]).
+        if health_delta != 0 {
+            self.player_health = (self.player_health as i64 + health_delta)
+                .clamp(0, self.max_health as i64) as u32;
+        }
         for (color, present) in key_changes {
             if !self.player_keys.set_by_name(&color, present) {
                 self.log.push(LogLine::error(format!("set_key: unknown color {color:?}")));

kiln-core/src/script.rs

@@ -59,7 +59,7 @@
 //! `move(dir)`, `delay(secs)`, `now()`, `set_tile(n)`, `log(msg)`, `say(msg)`,
 //! `set_fg(fg)`, `set_bg(bg)`, `set_color(fg, bg)`, `set_tag(target, tag, present)`,
 //! `send(target_id, fn_name [, arg])`, `teleport(x, y)`, `push(x, y, dir)`,
-//! `swap([[src_x, src_y, dst_x, dst_y], …])`, `add_gems(n)`, `set_key(color, present)`, `die()`
+//! `swap([[src_x, src_y, dst_x, dst_y], …])`, `add_gems(n)`, `alter_health(dh)`, `set_key(color, present)`, `die()`
 //!
 //! ## Queue API
 //!
@@ -906,6 +906,12 @@ fn register_write_api(engine: &mut Engine, queues: &QueueMap) {
         emit(&q, source_of(&ctx), Action::AddGems(n));
     });
 
+    // alter_health(dh): change the player's health by dh (clamped to [0, max_health]).
+    let q = queues.clone();
+    engine.register_fn("alter_health", move |ctx: NativeCallContext, dh: i64| {
+        emit(&q, source_of(&ctx), Action::AlterHealth(dh));
+    });
+
     // set_key(color, present): give (true) or take (false) the named key color.
     let q = queues.clone();
     engine.register_fn(

kiln-core/src/scripts/heart.rhai

@@ -0,0 +1,8 @@
+// Built-in script for the `heart` archetype.
+//
+// A heart is a grabbable collectible: walking onto it fires `grab()` instead
+// of blocking. It restores 1 health and removes itself from the board.
+fn grab() {
+    alter_health(1);
+    die();
+}