start adding clip

azalea-core/src/block_hit_result.rs

@@ -8,3 +8,15 @@ pub struct BlockHitResult {
     pub miss: bool,
     pub inside: bool,
 }
+
+impl BlockHitResult {
+    pub fn miss(location: Vec3, direction: Direction, block_pos: BlockPos) -> Self {
+        Self {
+            location,
+            direction,
+            block_pos,
+            miss: true,
+            inside: false,
+        }
+    }
+}

azalea-core/src/direction.rs

@@ -1,5 +1,7 @@
 use azalea_buf::McBuf;
 
+use crate::Vec3;
+
 #[derive(Clone, Copy, Debug, McBuf, Default)]
 pub enum Direction {
     #[default]
@@ -11,6 +13,43 @@ pub enum Direction {
     East,
 }
 
+impl Direction {
+    pub fn nearest(vec: Vec3) -> Direction {
+        let mut best_direction = Direction::North;
+        let mut best_direction_amount = 0.0;
+
+        for dir in [
+            Direction::Down,
+            Direction::Up,
+            Direction::North,
+            Direction::South,
+            Direction::West,
+            Direction::East,
+        ]
+        .iter()
+        {
+            let amount = dir.normal().dot(vec);
+            if amount > best_direction_amount {
+                best_direction = *dir;
+                best_direction_amount = amount;
+            }
+        }
+
+        best_direction
+    }
+
+    pub fn normal(self) -> Vec3 {
+        match self {
+            Direction::Down => Vec3::new(0.0, -1.0, 0.0),
+            Direction::Up => Vec3::new(0.0, 1.0, 0.0),
+            Direction::North => Vec3::new(0.0, 0.0, -1.0),
+            Direction::South => Vec3::new(0.0, 0.0, 1.0),
+            Direction::West => Vec3::new(-1.0, 0.0, 0.0),
+            Direction::East => Vec3::new(1.0, 0.0, 0.0),
+        }
+    }
+}
+
 // TODO: make azalea_block use this instead of FacingCardinal
 #[derive(Clone, Copy, Debug, McBuf)]
 pub enum CardinalDirection {

azalea-core/src/position.rs

@@ -36,6 +36,10 @@ macro_rules! vec3_impl {
                     z: self.z,
                 }
             }
+
+            pub fn dot(&self, other: Self) -> $type {
+                self.x * other.x + self.y * other.y + self.z * other.z
+            }
         }
 
         impl Add for &$name {

azalea-physics/src/clip.rs

@@ -1,11 +1,52 @@
-use azalea_core::{lerp, BlockPos, Vec3, EPSILON};
+use azalea_core::{lerp, BlockHitResult, BlockPos, Direction, Vec3, EPSILON};
+use azalea_world::ChunkStorage;
+
+pub struct ClipContext {
+    pub from: Vec3,
+    pub to: Vec3,
+    pub block: BlockClipContext,
+    pub fluid: FluidClipContext,
+    pub collision_context: CollisionContext,
+}
+
+pub struct BlockClipContext {
+    pub shape_getter
+}
+pub struct FluidClipContext {}
+pub struct CollisionContext {}
+
+pub fn clip(chunk_storage: &mut ChunkStorage, context: ClipContext) -> BlockHitResult {
+    traverse_blocks(
+        context.from,
+        context.to,
+        context,
+        |context, block_pos| {
+            let block_state = chunk_storage.get_block_state(block_pos);
+            // TODO: add fluid stuff to this (see getFluidState in vanilla source)
+            let block_shape = context.block_shape(block_state, chunk_storage, block_pos);
+            let block_hit_result =
+                chunk_storage.clip_with_interaction_override(context.from, context.to, block_pos);
+            // let block_distance =
+
+            None
+        },
+        |context| {
+            let vec = context.from - context.to;
+            BlockHitResult::miss(
+                context.to,
+                Direction::nearest(vec),
+                BlockPos::from(context.to),
+            )
+        },
+    )
+}
 
 pub fn traverse_blocks<C, T>(
     from: Vec3,
     to: Vec3,
     context: C,
-    get_hit_result: fn(&C, &BlockPos) -> Option<T>,
-    get_miss_result: fn(&C) -> T,
+    get_hit_result: impl Fn(&C, &BlockPos) -> Option<T>,
+    get_miss_result: impl Fn(&C) -> T,
 ) -> T {
     if from == to {
         return get_miss_result(&context);

azalea-protocol/Cargo.toml

@@ -21,9 +21,13 @@ azalea-brigadier = { path = "../azalea-brigadier", version = "^0.6.0", features
 ] }
 azalea-buf = { path = "../azalea-buf", version = "^0.6.0" }
 azalea-chat = { path = "../azalea-chat", version = "^0.6.0" }
-azalea-core = { path = "../azalea-core", optional = true, version = "^0.6.0", features = ["serde"]}
+azalea-core = { path = "../azalea-core", optional = true, version = "^0.6.0", features = [
+    "serde",
+] }
 azalea-crypto = { path = "../azalea-crypto", version = "^0.6.0" }
-azalea-nbt = { path = "../azalea-nbt", version = "^0.6.0", features = ["serde"] }
+azalea-nbt = { path = "../azalea-nbt", version = "^0.6.0", features = [
+    "serde",
+] }
 azalea-protocol-macros = { path = "./azalea-protocol-macros", version = "^0.6.0" }
 azalea-registry = { path = "../azalea-registry", version = "^0.6.0" }
 azalea-world = { path = "../azalea-world", version = "^0.6.0" }