implement fluid_shape

8 files changed, 145 insertions, 33 deletions

diff --git a/Cargo.lock b/Cargo.lock
index a6081a95..60b0a0df 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -463,6 +463,7 @@ dependencies = [
  "bevy_ecs",
  "bevy_time",
  "parking_lot",
+ "tracing",
  "uuid",
 ]
 
diff --git a/azalea-block/src/lib.rs b/azalea-block/src/lib.rs
index 65dd581e..4719ef42 100755
--- a/azalea-block/src/lib.rs
+++ b/azalea-block/src/lib.rs
@@ -8,7 +8,8 @@ mod range;
 use core::fmt::Debug;
 use std::{
     any::Any,
-    io::{Cursor, Write},
+    fmt,
+    io::{self, Cursor, Write},
 };
 
 use azalea_buf::{AzaleaRead, AzaleaReadVar, AzaleaWrite, AzaleaWriteVar, BufReadError};
@@ -115,13 +116,13 @@ impl AzaleaRead for BlockState {
     }
 }
 impl AzaleaWrite for BlockState {
-    fn azalea_write(&self, buf: &mut impl Write) -> Result<(), std::io::Error> {
+    fn azalea_write(&self, buf: &mut impl Write) -> Result<(), io::Error> {
         u32::azalea_write_var(&(self.id as u32), buf)
     }
 }
 
-impl std::fmt::Debug for BlockState {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+impl Debug for BlockState {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(
             f,
             "BlockState(id: {}, {:?})",
@@ -134,50 +135,69 @@ impl std::fmt::Debug for BlockState {
 #[derive(Clone, Debug)]
 pub struct FluidState {
     pub fluid: azalea_registry::Fluid,
-    pub height: u8,
+    /// 0 = empty, 8 = full, 9 = max.
+    ///
+    /// 9 is meant to be used when there's another fluid block of the same type
+    /// above it, but it's usually unused by this struct.
+    pub amount: u8,
+}
+impl FluidState {
+    /// A floating point number in between 0 and 1 representing the height (as a
+    /// percentage of a full block) of the fluid.
+    pub fn height(&self) -> f32 {
+        self.amount as f32 / 9.
+    }
 }
 
 impl Default for FluidState {
     fn default() -> Self {
         Self {
             fluid: azalea_registry::Fluid::Empty,
-            height: 0,
+            amount: 0,
         }
     }
 }
 
 impl From<BlockState> for FluidState {
     fn from(state: BlockState) -> Self {
+        // note that 8 here might be treated as 9 in some cases if there's another fluid
+        // block of the same type above it
+
         if state
             .property::<crate::properties::Waterlogged>()
             .unwrap_or_default()
         {
             Self {
                 fluid: azalea_registry::Fluid::Water,
-                height: 15,
+                amount: 8,
             }
         } else {
             let block = Box::<dyn Block>::from(state);
             if let Some(water) = block.downcast_ref::<crate::blocks::Water>() {
                 Self {
                     fluid: azalea_registry::Fluid::Water,
-                    height: water.level as u8,
+                    amount: to_or_from_legacy_fluid_level(water.level as u8),
                 }
             } else if let Some(lava) = block.downcast_ref::<crate::blocks::Lava>() {
                 Self {
                     fluid: azalea_registry::Fluid::Lava,
-                    height: lava.level as u8,
+                    amount: to_or_from_legacy_fluid_level(lava.level as u8),
                 }
             } else {
                 Self {
                     fluid: azalea_registry::Fluid::Empty,
-                    height: 0,
+                    amount: 0,
                 }
             }
         }
     }
 }
 
+// see FlowingFluid.getLegacyLevel
+fn to_or_from_legacy_fluid_level(level: u8) -> u8 {
+    8_u8.saturating_sub(level)
+}
+
 impl From<FluidState> for BlockState {
     fn from(state: FluidState) -> Self {
         match state.fluid {
@@ -185,14 +205,14 @@ impl From<FluidState> for BlockState {
             azalea_registry::Fluid::Water | azalea_registry::Fluid::FlowingWater => {
                 BlockState::from(crate::blocks::Water {
                     level: crate::properties::WaterLevel::from(
-                        state.height as BlockStateIntegerRepr,
+                        state.amount as BlockStateIntegerRepr,
                     ),
                 })
             }
             azalea_registry::Fluid::Lava | azalea_registry::Fluid::FlowingLava => {
                 BlockState::from(crate::blocks::Lava {
                     level: crate::properties::LavaLevel::from(
-                        state.height as BlockStateIntegerRepr,
+                        state.amount as BlockStateIntegerRepr,
                     ),
                 })
             }
diff --git a/azalea-entity/src/plugin/mod.rs b/azalea-entity/src/plugin/mod.rs
index 90d7f1c5..92918c69 100644
--- a/azalea-entity/src/plugin/mod.rs
+++ b/azalea-entity/src/plugin/mod.rs
@@ -104,7 +104,7 @@ pub fn update_fluid_on_eyes(
             .read()
             .get_fluid_state(&eye_block_pos)
             .unwrap_or_default();
-        let fluid_cutoff_y = eye_block_pos.y as f64 + (fluid_at_eye.height as f64 / 16f64);
+        let fluid_cutoff_y = eye_block_pos.y as f64 + (fluid_at_eye.amount as f64 / 16f64);
         if fluid_cutoff_y > adjusted_eye_y {
             **fluid_on_eyes = fluid_at_eye.fluid;
         } else {
diff --git a/azalea-physics/Cargo.toml b/azalea-physics/Cargo.toml
index 8b963d06..60d80787 100644
--- a/azalea-physics/Cargo.toml
+++ b/azalea-physics/Cargo.toml
@@ -19,4 +19,5 @@ azalea-registry = { path = "../azalea-registry", version = "0.11.0" }
 azalea-world = { path = "../azalea-world", version = "0.11.0" }
 bevy_app = { workspace = true }
 bevy_ecs = { workspace = true }
+tracing = { workspace = true }
 parking_lot = { workspace = true }
diff --git a/azalea-physics/src/clip.rs b/azalea-physics/src/clip.rs
index fd6bbf0b..4a374f58 100644
--- a/azalea-physics/src/clip.rs
+++ b/azalea-physics/src/clip.rs
@@ -20,12 +20,11 @@ pub struct ClipContext {
     // pub collision_context: EntityCollisionContext,
 }
 impl ClipContext {
-    // minecraft passes in the world and blockpos here... but it doesn't actually
-    // seem necessary?
-
     /// Get the shape of given block, using the type of shape set in
     /// [`Self::block_shape_type`].
     pub fn block_shape(&self, block_state: BlockState) -> &VoxelShape {
+        // minecraft passes in the world and blockpos to this function but it's not
+        // actually necessary. it is for fluid_shape though
         match self.block_shape_type {
             BlockShapeType::Collider => block_state.collision_shape(),
             BlockShapeType::Outline => block_state.outline_shape(),
@@ -41,6 +40,19 @@ impl ClipContext {
             }
         }
     }
+
+    pub fn fluid_shape(
+        &self,
+        fluid_state: FluidState,
+        world: &ChunkStorage,
+        pos: &BlockPos,
+    ) -> &VoxelShape {
+        if self.fluid_pick_type.can_pick(&fluid_state) {
+            crate::collision::fluid_shape(&fluid_state, world, pos)
+        } else {
+            &EMPTY_SHAPE
+        }
+    }
 }
 
 #[derive(Debug, Copy, Clone)]
@@ -63,6 +75,17 @@ pub enum FluidPickType {
     Any,
     Water,
 }
+impl FluidPickType {
+    pub fn can_pick(&self, fluid_state: &FluidState) -> bool {
+        match self {
+            Self::None => false,
+            Self::SourceOnly => fluid_state.amount == 8,
+            Self::Any => fluid_state.fluid != azalea_registry::Fluid::Empty,
+            Self::Water => fluid_state.fluid == azalea_registry::Fluid::Water,
+        }
+    }
+}
+
 #[derive(Debug, Clone)]
 pub struct EntityCollisionContext {
     pub descending: bool,
@@ -81,15 +104,29 @@ pub fn clip(chunk_storage: &ChunkStorage, context: ClipContext) -> BlockHitResul
             let block_state = chunk_storage.get_block_state(block_pos).unwrap_or_default();
             let fluid_state = FluidState::from(block_state);
 
-            // TODO: add fluid stuff to this (see getFluidState in vanilla source)
             let block_shape = ctx.block_shape(block_state);
+            let interaction_clip = clip_with_interaction_override(
+                &ctx.from,
+                &ctx.to,
+                block_pos,
+                block_shape,
+                &block_state,
+            );
+            let fluid_shape = ctx.fluid_shape(fluid_state, chunk_storage, block_pos);
+            let fluid_clip = fluid_shape.clip(&ctx.from, &ctx.to, block_pos);
 
-            clip_with_interaction_override(&ctx.from, &ctx.to, block_pos, block_shape, &block_state)
-            // let block_distance = if let Some(block_hit_result) =
-            // block_hit_result {     context.from.distance_squared_to(&
-            // block_hit_result.location) } else {
-            //     f64::INFINITY
-            // };
+            let distance_to_interaction = interaction_clip
+                .map(|hit| ctx.from.distance_squared_to(&hit.location))
+                .unwrap_or(f64::MAX);
+            let distance_to_fluid = fluid_clip
+                .map(|hit| ctx.from.distance_squared_to(&hit.location))
+                .unwrap_or(f64::MAX);
+
+            if distance_to_interaction <= distance_to_fluid {
+                interaction_clip
+            } else {
+                fluid_clip
+            }
         },
         |context| {
             let vec = context.from - context.to;
@@ -107,9 +144,10 @@ fn clip_with_interaction_override(
     to: &Vec3,
     block_pos: &BlockPos,
     block_shape: &VoxelShape,
-    block_state: &BlockState,
+    _block_state: &BlockState,
 ) -> Option<BlockHitResult> {
     let block_hit_result = block_shape.clip(from, to, block_pos);
+
     if let Some(block_hit_result) = block_hit_result {
         // TODO: minecraft calls .getInteractionShape here
         // getInteractionShape is empty for almost every shape except cauldons,
@@ -123,9 +161,10 @@ fn clip_with_interaction_override(
                 return Some(block_hit_result.with_direction(interaction_hit_result.direction));
             }
         }
+
         Some(block_hit_result)
     } else {
-        block_hit_result
+        None
     }
 }
 
diff --git a/azalea-physics/src/collision/mod.rs b/azalea-physics/src/collision/mod.rs
index 913cedac..bff9d6f8 100644
--- a/azalea-physics/src/collision/mod.rs
+++ b/azalea-physics/src/collision/mod.rs
@@ -4,14 +4,21 @@ mod mergers;
 mod shape;
 mod world_collisions;
 
-use std::ops::Add;
-
-use azalea_core::{aabb::AABB, direction::Axis, math::EPSILON, position::Vec3};
-use azalea_world::{Instance, MoveEntityError};
+use std::{ops::Add, sync::LazyLock};
+
+use azalea_block::FluidState;
+use azalea_core::{
+    aabb::AABB,
+    direction::Axis,
+    math::EPSILON,
+    position::{BlockPos, Vec3},
+};
+use azalea_world::{ChunkStorage, Instance, MoveEntityError};
 use bevy_ecs::world::Mut;
 pub use blocks::BlockWithShape;
 pub use discrete_voxel_shape::*;
 pub use shape::*;
+use tracing::warn;
 
 use self::world_collisions::get_block_collisions;
 
@@ -333,3 +340,48 @@ fn collide_with_shapes(
         z: z_movement,
     }
 }
+
+/// Get the [`VoxelShape`] for the given fluid state.
+///
+/// The instance and position are required so it can check if the block above is
+/// also the same fluid type.
+pub fn fluid_shape(
+    fluid: &FluidState,
+    world: &ChunkStorage,
+    pos: &BlockPos,
+) -> &'static VoxelShape {
+    if fluid.amount == 9 {
+        let fluid_state_above = world.get_fluid_state(&pos.up(1)).unwrap_or_default();
+        if fluid_state_above.fluid == fluid.fluid {
+            return &BLOCK_SHAPE;
+        }
+    }
+
+    // pre-calculate these in a LazyLock so this function can return a
+    // reference instead
+
+    static FLUID_SHAPES: LazyLock<[VoxelShape; 10]> = LazyLock::new(|| {
+        [
+            calculate_shape_for_fluid(0),
+            calculate_shape_for_fluid(1),
+            calculate_shape_for_fluid(2),
+            calculate_shape_for_fluid(3),
+            calculate_shape_for_fluid(4),
+            calculate_shape_for_fluid(5),
+            calculate_shape_for_fluid(6),
+            calculate_shape_for_fluid(7),
+            calculate_shape_for_fluid(8),
+            calculate_shape_for_fluid(9),
+        ]
+    });
+
+    if fluid.amount > 9 {
+        warn!("Tried to calculate shape for fluid with height > 9: {fluid:?} at {pos}");
+        return &EMPTY_SHAPE;
+    }
+
+    &FLUID_SHAPES[fluid.amount as usize]
+}
+fn calculate_shape_for_fluid(amount: u8) -> VoxelShape {
+    box_shape(0.0, 0.0, 0.0, 1.0, (f32::from(amount) / 9.0) as f64, 1.0)
+}
diff --git a/azalea-physics/src/collision/shape.rs b/azalea-physics/src/collision/shape.rs
index e7ac9c2e..fb733cae 100755
--- a/azalea-physics/src/collision/shape.rs
+++ b/azalea-physics/src/collision/shape.rs
@@ -413,7 +413,7 @@ impl VoxelShape {
             VoxelShape::Cube(s) => s.find_index(axis, coord),
             _ => {
                 let upper_limit = (self.shape().size(axis) + 1) as i32;
-                binary_search(0, upper_limit, &|t| coord < self.get(axis, t as usize)) - 1
+                binary_search(0, upper_limit, |t| coord < self.get(axis, t as usize)) - 1
             }
         }
     }
diff --git a/azalea/src/pathfinder/mod.rs b/azalea/src/pathfinder/mod.rs
index 9f8f9052..01375590 100644
--- a/azalea/src/pathfinder/mod.rs
+++ b/azalea/src/pathfinder/mod.rs
@@ -340,8 +340,6 @@ pub fn calculate_path(opts: CalculatePathOpts) -> Option<PathFoundEvent> {
         call_successors_fn(&cached_world, &opts.mining_cache, opts.successors_fn, pos)
     };
 
-    let path;
-
     let start_time = Instant::now();
 
     let astar::Path {
@@ -375,7 +373,7 @@ pub fn calculate_path(opts: CalculatePathOpts) -> Option<PathFoundEvent> {
         debug!("  {}", movement.target.apply(origin));
     }
 
-    path = movements.into_iter().collect::<VecDeque<_>>();
+    let path = movements.into_iter().collect::<VecDeque<_>>();
 
     let goto_id_now = opts.goto_id_atomic.load(atomic::Ordering::SeqCst);
     if goto_id != goto_id_now {
@@ -520,6 +518,7 @@ pub fn path_found_listener(
     }
 }
 
+#[allow(clippy::type_complexity)]
 pub fn timeout_movement(
     mut query: Query<(
         Entity,