update movement code for 1.21.5 changes

fixes grim flags

7 files changed, 156 insertions, 31 deletions

diff --git a/azalea-client/src/plugins/movement.rs b/azalea-client/src/plugins/movement.rs
index e97d9ec1..e4778be1 100644
--- a/azalea-client/src/plugins/movement.rs
+++ b/azalea-client/src/plugins/movement.rs
@@ -1,6 +1,9 @@
 use std::{backtrace::Backtrace, io};
 
-use azalea_core::{position::Vec3, tick::GameTick};
+use azalea_core::{
+    position::{Vec2, Vec3},
+    tick::GameTick,
+};
 use azalea_entity::{
     Attributes, InLoadedChunk, Jumping, LastSentPosition, LookDirection, Physics, Position,
     metadata::Sprinting,
@@ -137,8 +140,7 @@ pub struct PhysicsState {
     pub trying_to_sprint: bool,
 
     pub move_direction: WalkDirection,
-    pub forward_impulse: f32,
-    pub left_impulse: f32,
+    pub move_vector: Vec2,
 }
 
 #[allow(clippy::type_complexity)]
@@ -308,12 +310,10 @@ pub fn send_sprinting_if_needed(
     }
 }
 
-/// Update the impulse from self.move_direction. The multiplier is used for
-/// sneaking.
+/// Updates the [`PhysicsState::move_vector`] based on the
+/// [`PhysicsState::move_direction`].
 pub(crate) fn tick_controls(mut query: Query<&mut PhysicsState>) {
     for mut physics_state in query.iter_mut() {
-        let multiplier: Option<f32> = None;
-
         let mut forward_impulse: f32 = 0.;
         let mut left_impulse: f32 = 0.;
         let move_direction = physics_state.move_direction;
@@ -337,13 +337,9 @@ pub(crate) fn tick_controls(mut query: Query<&mut PhysicsState>) {
             }
             _ => {}
         };
-        physics_state.forward_impulse = forward_impulse;
-        physics_state.left_impulse = left_impulse;
 
-        if let Some(multiplier) = multiplier {
-            physics_state.forward_impulse *= multiplier;
-            physics_state.left_impulse *= multiplier;
-        }
+        let move_vector = Vec2::new(left_impulse, forward_impulse).normalized();
+        physics_state.move_vector = move_vector;
     }
 }
 
@@ -357,8 +353,12 @@ pub fn local_player_ai_step(
 ) {
     for (physics_state, mut physics, mut sprinting, mut attributes) in query.iter_mut() {
         // server ai step
-        physics.x_acceleration = physics_state.left_impulse;
-        physics.z_acceleration = physics_state.forward_impulse;
+
+        // TODO: replace those booleans when using items, passengers, and sneaking are
+        // properly implemented
+        let move_vector = modify_input(physics_state.move_vector, false, false, false, &attributes);
+        physics.x_acceleration = move_vector.x;
+        physics.z_acceleration = move_vector.y;
 
         // TODO: food data and abilities
         // let has_enough_food_to_sprint = self.food_data().food_level ||
@@ -385,6 +385,47 @@ pub fn local_player_ai_step(
     }
 }
 
+// LocalPlayer.modifyInput
+fn modify_input(
+    mut move_vector: Vec2,
+    is_using_item: bool,
+    is_passenger: bool,
+    moving_slowly: bool,
+    attributes: &Attributes,
+) -> Vec2 {
+    if move_vector.length_squared() == 0. {
+        return move_vector;
+    }
+
+    move_vector *= 0.98;
+    if is_using_item && !is_passenger {
+        move_vector *= 0.2;
+    }
+
+    if moving_slowly {
+        let sneaking_speed = attributes.sneaking_speed.calculate() as f32;
+        move_vector *= sneaking_speed;
+    }
+
+    modify_input_speed_for_square_movement(move_vector)
+}
+fn modify_input_speed_for_square_movement(move_vector: Vec2) -> Vec2 {
+    let length = move_vector.length();
+    if length == 0. {
+        return move_vector;
+    }
+    let scaled_to_inverse_length = move_vector * (1. / length);
+    let dist = distance_to_unit_square(scaled_to_inverse_length);
+    let scale = (length * dist).min(1.);
+    scaled_to_inverse_length * scale
+}
+fn distance_to_unit_square(v: Vec2) -> f32 {
+    let x = v.x.abs();
+    let y = v.y.abs();
+    let ratio = if y > x { x / y } else { y / x };
+    (1.0 + ratio * ratio).sqrt()
+}
+
 impl Client {
     /// Start walking in the given direction. To sprint, use
     /// [`Client::sprint`]. To stop walking, call walk with
@@ -508,7 +549,7 @@ fn has_enough_impulse_to_start_sprinting(physics_state: &PhysicsState) -> bool {
     // if self.underwater() {
     //     self.has_forward_impulse()
     // } else {
-    physics_state.forward_impulse > 0.8
+    physics_state.move_vector.y > 0.8
     // }
 }
 
diff --git a/azalea-core/src/bitset.rs b/azalea-core/src/bitset.rs
index 2a3e5b51..fbb12ee0 100644
--- a/azalea-core/src/bitset.rs
+++ b/azalea-core/src/bitset.rs
@@ -151,6 +151,10 @@ where
         }
     }
 
+    pub const fn new_with_data(data: [u8; bits_to_bytes(N)]) -> Self {
+        FixedBitSet { data }
+    }
+
     #[inline]
     pub fn index(&self, index: usize) -> bool {
         (self.data[index / 8] & (1u8 << (index % 8))) != 0
diff --git a/azalea-core/src/position.rs b/azalea-core/src/position.rs
index c0c25639..dd6a37e0 100644
--- a/azalea-core/src/position.rs
+++ b/azalea-core/src/position.rs
@@ -818,6 +818,66 @@ impl fmt::Display for Vec3 {
     }
 }
 
+/// A 2D vector.
+#[derive(Clone, Copy, Debug, Default, PartialEq, AzBuf)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
+pub struct Vec2 {
+    pub x: f32,
+    pub y: f32,
+}
+impl Vec2 {
+    const ZERO: Vec2 = Vec2 { x: 0.0, y: 0.0 };
+
+    #[inline]
+    pub fn new(x: f32, y: f32) -> Self {
+        Vec2 { x, y }
+    }
+    #[inline]
+    pub fn scale(&self, amount: f32) -> Self {
+        Vec2 {
+            x: self.x * amount,
+            y: self.y * amount,
+        }
+    }
+    #[inline]
+    pub fn dot(&self, other: Vec2) -> f32 {
+        self.x * other.x + self.y * other.y
+    }
+    #[inline]
+    pub fn normalized(&self) -> Self {
+        let length = (self.x * self.x + self.y * self.y).sqrt();
+        if length < 1e-4 {
+            return Vec2::ZERO;
+        }
+        Vec2 {
+            x: self.x / length,
+            y: self.y / length,
+        }
+    }
+    #[inline]
+    pub fn length_squared(&self) -> f32 {
+        self.x * self.x + self.y * self.y
+    }
+    #[inline]
+    pub fn length(&self) -> f32 {
+        self.length_squared().sqrt()
+    }
+}
+impl Mul<f32> for Vec2 {
+    type Output = Self;
+
+    #[inline]
+    fn mul(self, rhs: f32) -> Self::Output {
+        self.scale(rhs)
+    }
+}
+impl MulAssign<f32> for Vec2 {
+    #[inline]
+    fn mul_assign(&mut self, rhs: f32) {
+        *self = self.scale(rhs);
+    }
+}
+
 const PACKED_X_LENGTH: u64 = 1 + 25; // minecraft does something a bit more complicated to get this 25
 const PACKED_Z_LENGTH: u64 = PACKED_X_LENGTH;
 const PACKED_Y_LENGTH: u64 = 64 - PACKED_X_LENGTH - PACKED_Z_LENGTH;
diff --git a/azalea-entity/src/attributes.rs b/azalea-entity/src/attributes.rs
index 7af845f8..c2a22e9b 100644
--- a/azalea-entity/src/attributes.rs
+++ b/azalea-entity/src/attributes.rs
@@ -10,6 +10,7 @@ use thiserror::Error;
 #[derive(Clone, Debug, Component)]
 pub struct Attributes {
     pub speed: AttributeInstance,
+    pub sneaking_speed: AttributeInstance,
     pub attack_speed: AttributeInstance,
     pub water_movement_efficiency: AttributeInstance,
 
@@ -92,7 +93,7 @@ pub enum AttributeModifierOperation {
 pub fn sprinting_modifier() -> AttributeModifier {
     AttributeModifier {
         id: ResourceLocation::new("sprinting"),
-        amount: 0.30000001192092896,
+        amount: 0.3f32 as f64,
         operation: AttributeModifierOperation::MultiplyTotal,
     }
 }
diff --git a/azalea-entity/src/lib.rs b/azalea-entity/src/lib.rs
index 340b6f25..18e9e1a1 100644
--- a/azalea-entity/src/lib.rs
+++ b/azalea-entity/src/lib.rs
@@ -50,10 +50,10 @@ pub fn move_relative(
 
 pub fn input_vector(direction: LookDirection, speed: f32, acceleration: Vec3) -> Vec3 {
     let distance = acceleration.length_squared();
-    if distance < 1.0E-7 {
+    if distance < 1.0e-7 {
         return Vec3::ZERO;
     }
-    let acceleration = if distance > 1.0 {
+    let acceleration = if distance > 1. {
         acceleration.normalize()
     } else {
         acceleration
@@ -492,6 +492,7 @@ pub fn default_attributes(_entity_kind: EntityKind) -> Attributes {
     // entities have different defaults
     Attributes {
         speed: AttributeInstance::new(0.1),
+        sneaking_speed: AttributeInstance::new(0.3),
         attack_speed: AttributeInstance::new(4.0),
         water_movement_efficiency: AttributeInstance::new(0.0),
         block_interaction_range: AttributeInstance::new(4.5),
diff --git a/azalea-physics/src/lib.rs b/azalea-physics/src/lib.rs
index 772b9b86..9481cef7 100644
--- a/azalea-physics/src/lib.rs
+++ b/azalea-physics/src/lib.rs
@@ -15,10 +15,10 @@ use azalea_core::{
     tick::GameTick,
 };
 use azalea_entity::{
-    Attributes, InLoadedChunk, Jumping, LocalEntity, LookDirection, OnClimbable, Physics, Pose,
-    Position, metadata::Sprinting, move_relative,
+    Attributes, EntityKindComponent, InLoadedChunk, Jumping, LocalEntity, LookDirection,
+    OnClimbable, Physics, Pose, Position, metadata::Sprinting, move_relative,
 };
-use azalea_registry::Block;
+use azalea_registry::{Block, EntityKind};
 use azalea_world::{Instance, InstanceContainer, InstanceName};
 use bevy_app::{App, Plugin};
 use bevy_ecs::prelude::*;
@@ -66,12 +66,17 @@ pub fn ai_step(
             &LookDirection,
             &Sprinting,
             &InstanceName,
+            &EntityKindComponent,
         ),
         (With<LocalEntity>, With<InLoadedChunk>),
     >,
     instance_container: Res<InstanceContainer>,
 ) {
-    for (mut physics, jumping, position, look_direction, sprinting, instance_name) in &mut query {
+    for (mut physics, jumping, position, look_direction, sprinting, instance_name, entity_kind) in
+        &mut query
+    {
+        let is_player = **entity_kind == EntityKind::Player;
+
         // vanilla does movement interpolation here, doesn't really matter much for a
         // bot though
 
@@ -79,14 +84,29 @@ pub fn ai_step(
             physics.no_jump_delay -= 1;
         }
 
-        if physics.velocity.x.abs() < 0.003 {
-            physics.velocity.x = 0.;
+        if is_player {
+            if physics.velocity.horizontal_distance_squared() < 9.0e-6 {
+                physics.velocity.x = 0.;
+                physics.velocity.z = 0.;
+            }
+        } else {
+            if physics.velocity.x.abs() < 0.003 {
+                physics.velocity.x = 0.;
+            }
+            if physics.velocity.z.abs() < 0.003 {
+                physics.velocity.z = 0.;
+            }
         }
+
         if physics.velocity.y.abs() < 0.003 {
             physics.velocity.y = 0.;
         }
-        if physics.velocity.z.abs() < 0.003 {
-            physics.velocity.z = 0.;
+
+        if is_player {
+            // handled in local_player_ai_step
+        } else {
+            physics.x_acceleration *= 0.98;
+            physics.z_acceleration *= 0.98;
         }
 
         if jumping == Some(&Jumping(true)) {
@@ -128,9 +148,6 @@ pub fn ai_step(
             physics.no_jump_delay = 0;
         }
 
-        physics.x_acceleration *= 0.98;
-        physics.z_acceleration *= 0.98;
-
         // TODO: freezing, pushEntities, drowning damage (in their own systems,
         // after `travel`)
     }
diff --git a/azalea-protocol/src/common/movements.rs b/azalea-protocol/src/common/movements.rs
index e88fb87e..6475b46f 100644
--- a/azalea-protocol/src/common/movements.rs
+++ b/azalea-protocol/src/common/movements.rs
@@ -94,7 +94,8 @@ fn apply_change<T: Add<Output = T>>(base: T, condition: bool, change: T) -> T {
 impl AzaleaRead for RelativeMovements {
     fn azalea_read(buf: &mut Cursor<&[u8]>) -> Result<Self, BufReadError> {
         // yes minecraft seriously wastes that many bits, smh
-        let set = FixedBitSet::<32>::azalea_read(buf)?;
+        let set = u32::azalea_read(buf)?;
+        let set = FixedBitSet::<32>::new_with_data(set.swap_bytes().to_be_bytes());
         Ok(RelativeMovements {
             x: set.index(0),
             y: set.index(1),