Mushroom groves: unclaimable moss where giant mushrooms grow slowly and glow when ready to fell

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/map.rs

@@ -70,10 +70,14 @@ pub enum Kind {
     Altar,      // room: sacrifices
     Drawbridge, // bridge that can be raised (res: see DB_RAISED, DB_AUTO, DB_LAVA)
     Obsidian,   // lava cooled by frost: walkable until it melts again
-    Mushroom,   // giant mushroom on open ground: imps fell it for wood (grows back)
+    Mushroom,   // giant mushroom: imps fell it for wood once it is grown (food: growth left, 0 = grown; res: MUSH_GROVE)
     Tree,       // tree above ground: imps fell it for wood
+    Grove,      // mushroom grove: mossy ground nobody can claim, giant mushrooms grow (back) here
 }
 
+// a giant mushroom of a grove: when felled, the ground turns back into grove (Tile::res)
+pub const MUSH_GROVE: u8 = 1;
+
 // drawbridge state in Tile::res
 pub const DB_RAISED: u8 = 1; // raised: nobody can cross
 pub const DB_AUTO: u8 = 2; // rises by itself when enemies come near
@@ -105,7 +109,7 @@ pub struct River {
 }
 
 // order matters for the packed savegame codec: only append new kinds
-const KINDS: [Kind; 38] = [
+const KINDS: [Kind; 39] = [
     Kind::Rock,
     Kind::Earth,
     Kind::Gold,
@@ -144,6 +148,7 @@ const KINDS: [Kind; 38] = [
     Kind::Obsidian,
     Kind::Mushroom,
     Kind::Tree,
+    Kind::Grove,
 ];
 
 // treasures (veins, treasury content, imp loads): 0 gold, 1 silver, 2 ruby, 3 diamond
@@ -229,7 +234,15 @@ impl Tile {
         matches!(self.kind, Kind::Rock | Kind::Earth | Kind::Gold | Kind::Silver | Kind::Ruby | Kind::Diamond | Kind::Steel)
     }
     pub fn diggable(&self) -> bool {
-        matches!(self.kind, Kind::Earth | Kind::Gold | Kind::Silver | Kind::Ruby | Kind::Diamond | Kind::Steel | Kind::Mushroom | Kind::Tree)
+        matches!(self.kind, Kind::Earth | Kind::Gold | Kind::Silver | Kind::Ruby | Kind::Diamond | Kind::Steel | Kind::Tree) || (self.kind == Kind::Mushroom && self.grown())
+    }
+    // a giant mushroom is felled only when it is fully grown (everything else counts as grown)
+    pub fn grown(&self) -> bool {
+        self.kind != Kind::Mushroom || self.food <= 0.0
+    }
+    // how far a giant mushroom has grown: 0 a sprout .. 1 fully grown
+    pub fn growth(&self) -> f32 {
+        if self.kind == Kind::Mushroom { (1.0 - self.food).clamp(0.0, 1.0) } else { 1.0 }
     }
     // a giant mushroom or a tree: felled like a wall is dug, gives wood
     pub fn plant(&self) -> bool {
@@ -272,6 +285,7 @@ impl Tile {
                 | Kind::Arena
                 | Kind::Altar
                 | Kind::Obsidian
+                | Kind::Grove
         ) || (self.kind == Kind::Drawbridge && self.res & DB_RAISED == 0)
     }
     // river tiles (open, but nobody can walk there)