Add Fluff::PlaceBlockGeneric emitted by tool uses.

all-is-cubes/src/fluff.rs

@@ -5,11 +5,19 @@
 /// Each [`Fluff`] value represents the beginning of such an effect. It does not specify
 /// anything about the exact duration; the intent is that they should all be negligibly
 /// short.
+///
+/// Currently, all `Fluff` is an item from a fixed list. In the future, it will be able
+/// to refer to audio and visual assets defined in a `Universe`.
 #[derive(Debug, Clone, Hash, Eq, PartialEq)]
 #[non_exhaustive]
 pub enum Fluff {
     /// A standard beep/“bell” sound, as might be used for a notification or error.
     Beep,
+
     /// A sound suitable for “something was activated or done”, e.g. a button was clicked.
     Happened,
+
+    /// Sound and visual effect from a block having been placed in the game world
+    /// by player action, without any more specific overriding styling.
+    PlaceBlockGeneric,
 }

all-is-cubes/src/inv/tool.rs

@@ -355,6 +355,7 @@ impl ToolInput {
         old_block: Block,
         new_block: Block,
     ) -> Result<UniverseTransaction, ToolError> {
+        let affected_cube = cursor.cube() + cursor.face_selected().normal_vector();
         let rotation = match new_block
             .evaluate()
             .map_err(|e| ToolError::Internal(e.to_string()))? // TODO: better error typing here
@@ -375,11 +376,14 @@ impl ToolInput {
                     .unwrap_or(GridRotation::IDENTITY)
             }
         };
-        self.set_cube(
-            cursor.cube() + cursor.face_selected().normal_vector(),
-            old_block,
-            new_block.rotate(rotation),
-        )
+        let txn = self.set_cube(affected_cube, old_block, new_block.rotate(rotation))?;
+        let txn = txn
+            .merge(
+                SpaceTransaction::fluff(affected_cube, Fluff::PlaceBlockGeneric)
+                    .bind(self.cursor()?.space().clone()),
+            )
+            .expect("fluff never fails to merge");
+        Ok(txn)
     }
 
     /// Returns a [`Cursor`] indicating what blocks the tool should act on, if it is

all-is-cubes/src/space/space_txn.rs

@@ -159,10 +159,20 @@ impl SpaceTransaction {
     /// transaction is committed, in addition to other effects of the transaction.
     ///
     /// TODO: will eventually need rotation.
-    pub fn add_fluff(&mut self, cube: Cube, fluff: crate::fluff::Fluff) {
+    pub fn add_fluff(&mut self, cube: Cube, fluff: Fluff) {
         self.at(cube).fluff.push(fluff);
     }
 
+    /// Emit [`Fluff`] (sound/particle effects) located at the given cube when this
+    /// transaction is committed.
+    ///
+    /// TODO: will eventually need rotation.
+    pub fn fluff(cube: Cube, fluff: Fluff) -> Self {
+        let mut txn = Self::default();
+        txn.at(cube).fluff.push(fluff);
+        txn
+    }
+
     /// Computes the region of cubes directly affected by this transaction.
     /// Ignores behaviors.
     ///