Merge pull request #2514 from kacpherek/fix/amethyst-step-chime

🤖 Agent: Merged by Ludovic's AI agent (Claude, contrib-gate-19). Thanks @kacpherek: Play the amethyst chime when walking on amethyst blocks. I checked it against vanilla 26.3, and it passed every harness it reaches in a union with your other PRs, plus lan_e2e in both modes.

crates/horizon-client/src/game.rs

@@ -4740,6 +4740,14 @@ impl Game<'_> {
                     self.audio
                         .play("minecraft:entity.player.swim", Some(feet), volume, pitch);
                 }
+                MotionEvent::Chime { volume, pitch } => {
+                    self.audio.play(
+                        "minecraft:block.amethyst_block.chime",
+                        Some(feet),
+                        volume,
+                        pitch,
+                    );
+                }
                 MotionEvent::Drown => {
                     // LivingEntity.makeDrownParticles: eight bubbles moving
                     // with the player.

crates/horizon-client/src/game/remote.rs

@@ -3403,6 +3403,14 @@ impl Game<'_> {
                     self.audio
                         .play("minecraft:entity.player.swim", Some(feet), volume, pitch);
                 }
+                horizon_client::motion::MotionEvent::Chime { volume, pitch } => {
+                    self.audio.play(
+                        "minecraft:block.amethyst_block.chime",
+                        Some(feet),
+                        volume,
+                        pitch,
+                    );
+                }
                 // NetherPortalBlock.entityInside on the client's own level:
                 // the portal overlay and its trigger sound (the server moves
                 // the player).

crates/horizon-client/src/motion.rs

@@ -55,6 +55,8 @@ pub struct MotionResources {
     /// `BlockTags.SOUL_SPEED_BLOCKS`: what Soul Speed's effects look for.
     pub soul_speed_blocks: BTreeSet<String>,
     pub fall_reset: BTreeSet<String>,
+    /// `BlockTags.CRYSTAL_SOUND_BLOCKS`: blocks that chime under footsteps.
+    pub crystal_sound: BTreeSet<String>,
     pub landing: BlockLandingRegistry,
     pub health: crate::health::HealthResources,
     pub fluids: FluidResources,
@@ -115,6 +117,7 @@ impl MotionResources {
             glide_through: tag("minecraft:can_glide_through")?,
             soul_speed_blocks: tag("minecraft:soul_speed_blocks")?,
             fall_reset: tag("minecraft:fall_damage_resetting")?,
+            crystal_sound: tag("minecraft:crystal_sound_blocks")?,
         })
     }
 }
@@ -165,6 +168,11 @@ pub enum MotionEvent {
         state: BlockStateId,
         in_water: bool,
     },
+    /// `Entity.playAmethystStepSound`: `block.amethyst_block.chime`.
+    Chime {
+        volume: f32,
+        pitch: f32,
+    },
     /// `Entity.waterSwimSound`: `entity.player.swim`.
     Swim {
         volume: f32,
@@ -309,6 +317,10 @@ pub struct PlayerMotion {
     /// `Entity.moveDist`, `flyDist` and `nextStep`: footsteps come once per
     /// metre walked, not once per move.
     pub steps: MovementDistances,
+    /// `Entity.crystalSoundIntensity` and `lastCrystalSoundPlayTick`: the
+    /// amethyst chime grows with steps taken close together.
+    pub crystal_sound_intensity: f32,
+    pub last_crystal_sound_play_tick: i32,
     pub needs_sync: bool,
     pub sync_position: bool,
     /// Moved by an ender pearl (`ServerPlayer.teleport`): a server sends the
@@ -501,6 +513,8 @@ impl PlayerMotion {
                 next_step: 1.0,
                 ..MovementDistances::default()
             },
+            crystal_sound_intensity: 0.0,
+            last_crystal_sound_play_tick: 0,
             needs_sync: false,
             sync_position: false,
             teleported: false,
@@ -2164,6 +2178,30 @@ impl MovementEmissionWorld for MotionWorld<'_, '_, '_> {
             state,
             in_water,
         });
+        // Entity.walkingStepSound: the amethyst chime after the step.
+        let name = &self
+            .assets
+            .registry
+            .state(state)
+            .ok_or("missing scene state")?
+            .name;
+        let tick = self.player.health.tick_count;
+        if self.resources.crystal_sound.contains(name)
+            && tick >= self.player.last_crystal_sound_play_tick + 20
+        {
+            // Entity.playAmethystStepSound (the level random stands in for
+            // the entity's).
+            let elapsed = f64::from(tick - self.player.last_crystal_sound_play_tick);
+            let decayed = self.player.crystal_sound_intensity * 0.997_f64.powf(elapsed) as f32;
+            let intensity = 1.0_f32.min(decayed + 0.07);
+            self.player.crystal_sound_intensity = intensity;
+            let pitch = 0.5 + intensity * self.scene.random.next_float() * 1.2;
+            let volume = 0.1 + intensity * 1.2;
+            self.player
+                .events
+                .push(MotionEvent::Chime { volume, pitch });
+            self.player.last_crystal_sound_play_tick = tick;
+        }
         Ok(())
     }
     fn step_event(&mut self, _: BlockStateId) -> Result<()> {