gave up and limited recursion depth

kiln-core/src/board.rs

@@ -112,16 +112,16 @@ impl Board {
     ///
     /// With a single grid the draw order is a fixed precedence (no layer walk):
     ///
-    /// 1. the player (drawn on top; not part of the grid yet);
-    /// 2. an object at the cell — a solid object always, otherwise the first
-    ///    non-transparent non-solid object (`tile != 0`, so invisible objects exist);
-    /// 3. the grid cell `(glyph, arch)` — a solid always draws, a non-solid only when
-    ///    visible (`tile != 0`);
-    /// 4. a portal at the cell (portals sit on a transparent grid cell);
-    /// 5. a [`decoration`](Board::decorations) at the cell (reached only because the
-    ///    grid cell was empty);
-    /// 6. the [`floor`](Board::floor) glyph, if any;
-    /// 7. the canonical black `Empty` glyph.
+    /// 1. a sensor `Above` the grid whose glyph is visible (drawn on top of the
+    ///    player too);
+    /// 2. the grid cell's tile — the player or an object — when its glyph is
+    ///    visible (`tile != 0`, so invisible objects exist);
+    /// 3. a sensor `Below` the grid whose glyph is visible (only reachable
+    ///    because the grid cell drew nothing);
+    /// 4. a portal at the cell (portals sit on a transparent grid cell), when
+    ///    its glyph is visible;
+    /// 5. the [`floor`](Board::floor) glyph, if any;
+    /// 6. the canonical black `Empty` glyph.
     ///
     /// Panics if out of bounds.
     pub fn glyph_at<P: Into<Point>>(&self, p: P) -> Glyph {
@@ -145,6 +145,12 @@ impl Board {
             return below.scripting.glyph;
         }
 
+        // A portal at the cell, if its glyph is visible (a `tile = 0` portal is
+        // deliberately invisible, so the floor shows through instead).
+        if let Some(portal) = self.portal_at(p) && portal.glyph.is_visible() {
+            return portal.glyph;
+        }
+
         // Otherwise the floor, or the canonical black empty cell.
         self.floor.glyph_at(p, self.width).unwrap_or_else(Glyph::transparent)
     }

kiln-core/src/board_spec.rs

@@ -235,6 +235,7 @@ impl BoardSpec {
 mod tests {
     use super::BoardSpec;
     use crate::board::Board;
+    use crate::glyph::Glyph;
     use crate::tile::Tile;
     use std::collections::HashSet;
 
@@ -414,4 +415,59 @@ target_name = "other"
         // The same board converts once the world supplies that script.
         assert!(build(&toml_src, &["ghost"]).is_ok());
     }
+
+    /// A `[[portals]]` block with a default glyph, anchored at `(x, y)`.
+    fn portal_spec(x: usize, y: usize) -> String {
+        format!(
+            r#"
+[[portals]]
+x = {x}
+y = {y}
+name = "east_door"
+target_board = "room2"
+target_name = "west_door"
+"#
+        )
+    }
+
+    #[test]
+    fn a_portal_without_a_glyph_defaults_to_the_portal_glyph() {
+        let board = build(&spec_toml(3, 1, " @ ", &[PLAYER], &portal_spec(2, 0)), &[])
+            .expect("a portal with no glyph converts");
+        assert_eq!(board.portals[0].glyph, Glyph::portal());
+    }
+
+    #[test]
+    fn an_omitted_portal_glyph_round_trips_as_an_omitted_key() {
+        // The default portal glyph is not serialized — omission is how it round-trips.
+        let spec: BoardSpec =
+            toml::from_str(&spec_toml(3, 1, " @ ", &[PLAYER], &portal_spec(2, 0)))
+                .expect("board table parses");
+        let text = toml::to_string(&spec).unwrap();
+        assert!(!text.contains("glyph"), "default portal glyph is omitted: {text}");
+    }
+
+    #[test]
+    fn glyph_at_draws_a_visible_portal_but_not_a_transparent_one() {
+        // A portal with the default (visible) glyph renders at its cell…
+        let board = build(&spec_toml(3, 1, " @ ", &[PLAYER], &portal_spec(2, 0)), &[])
+            .expect("portals convert");
+        assert_eq!(board.glyph_at((2, 0)), Glyph::portal());
+
+        // …while an explicitly-transparent one (`tile = 0`) stays invisible, so the
+        // floor (here, blank) shows through instead — the sensor-like opt-out.
+        let invisible = r##"
+[[portals]]
+x = 2
+y = 0
+name = "east_door"
+target_board = "room2"
+target_name = "west_door"
+glyph = { tile = 0, fg = "#000000", bg = "#000000" }
+"##;
+        let board = build(&spec_toml(3, 1, " @ ", &[PLAYER], invisible), &[])
+            .expect("portals convert");
+        assert_eq!(board.portals[0].glyph, Glyph::transparent());
+        assert!(!board.glyph_at((2, 0)).is_visible());
+    }
 }

kiln-core/src/game.rs

@@ -74,6 +74,11 @@ pub struct GameState {
     /// position in [`Board::player`](crate::board::Board::player). Scripts mutate
     /// it via `alter_gems`/`alter_health`/`set_key` and read a snapshot of it.
     pub player: PlayerRef,
+    /// How many times we've called resolve_move since the last time this counter
+    /// was reset. Because it's impossible to determine whether a given move + its
+    /// triggered effects will ever terminate, we just cut it at a max limit of
+    /// recursions
+    pub resolve_move_recursion_level: u32
 }
 
 impl GameState {
@@ -102,6 +107,7 @@ impl GameState {
             speech_bubbles: Vec::new(),
             active_scroll: None,
             board_transition: None,
+            resolve_move_recursion_level: 0,
             player
         };
         state.drain_log();
@@ -202,6 +208,7 @@ impl GameState {
         // actions immediately so the next object sees the updated board.
         let ids = self.board().all_ids();
         for id in ids {
+            self.reset_resolve_move_limit(); // Each object gets an independent limit of resolve_move recursions
             let actions = self.scripts.run_tick_on(id, secs);
             self.apply_actions(actions);
         }
@@ -385,7 +392,18 @@ impl GameState {
         self.run_init();
     }
 
+    fn reset_resolve_move_limit(&mut self) {
+        self.resolve_move_recursion_level = 0;
+    }
+
     fn resolve_move<P: Into<Point>>(&mut self, from: P, dir: Direction) -> bool {
+        // Check the recursion level because we may already be over it:
+        if self.resolve_move_recursion_level > 100 {
+            self.log.push(LogLine::error("resolve_move recursion limit reached"));
+            return false;
+        }
+        self.resolve_move_recursion_level += 1;
+
         let from = from.into();
         // Get the target coords, if they're out of bounds then the move fails.
         let target: Point = dir.from_point(from);
@@ -441,6 +459,7 @@ impl GameState {
             return;
         }
 
+        self.reset_resolve_move_limit(); // Starting a new chain of moves, reset the limit
         self.resolve_move(player_loc, dir);
 
         // Check if we actually moved

kiln-core/src/glyph.rs

@@ -107,6 +107,13 @@ impl Glyph {
         }
     }
 
+    /// Whether this glyph is the canonical [`portal`](Glyph::portal) glyph;
+    /// keeps it out of saved map files, since omitting the field is how the
+    /// default round-trips.
+    pub fn is_portal_default(&self) -> bool {
+        self == &Self::portal()
+    }
+
     /// Whether this glyph draws anything at all.
     ///
     /// `false` for the [`transparent`](Glyph::transparent) sentinel, which is how

kiln-core/src/portal.rs

@@ -26,6 +26,12 @@ pub struct Portal {
     pub target_board: String,
     /// Name of the arrival portal on the target board.
     pub target_name: String,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub glyph: Option<Glyph>
+    /// Visual representation of this portal. Omitted from a map file, it
+    /// defaults to [`Glyph::portal`] — `≡`, black on white — so portals are
+    /// visible unless the author opts out with `tile = 0` (the transparent
+    /// sentinel). Unlike sensors (which are glyphless by default), a portal
+    /// sits on a transparent grid cell and this glyph is what
+    /// [`Board::glyph_at`](crate::board::Board::glyph_at) draws for it.
+    #[serde(default = "Glyph::portal", skip_serializing_if = "Glyph::is_portal_default")]
+    pub glyph: Glyph
 }

kiln-core/src/tests/game_portals.rs

@@ -7,6 +7,7 @@
 use crate::board::Board;
 use crate::board::tests::open_board;
 use crate::game::GameState;
+use crate::glyph::Glyph;
 use crate::portal::Portal;
 use crate::utils::{Direction, Point};
 use crate::world::World;
@@ -21,7 +22,8 @@ fn make_board(player: (usize, usize), portals: Vec<Portal>) -> Board {
     board
 }
 
-/// A glyphless portal at `(x, y)` pointing at `target_name` on `target_board`.
+/// A portal at `(x, y)` pointing at `target_name` on `target_board`, using the
+/// default portal glyph.
 fn portal(
     x: usize,
     y: usize,
@@ -34,7 +36,7 @@ fn portal(
         name: name.to_string(),
         target_board: target_board.to_string(),
         target_name: target_name.to_string(),
-        glyph: None,
+        glyph: Glyph::portal(),
     }
 }