azalea_client/
attack.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
use azalea_core::{game_type::GameMode, tick::GameTick};
use azalea_entity::{
    metadata::{ShiftKeyDown, Sprinting},
    update_bounding_box, Attributes, Physics,
};
use azalea_physics::PhysicsSet;
use azalea_protocol::packets::game::serverbound_interact_packet::{
    self, ServerboundInteractPacket,
};
use azalea_world::MinecraftEntityId;
use bevy_app::{App, Plugin, Update};
use bevy_ecs::prelude::*;
use derive_more::{Deref, DerefMut};

use crate::{
    interact::SwingArmEvent, local_player::LocalGameMode, movement::MoveEventsSet,
    packet_handling::game::SendPacketEvent, respawn::perform_respawn, Client,
};

pub struct AttackPlugin;
impl Plugin for AttackPlugin {
    fn build(&self, app: &mut App) {
        app.add_event::<AttackEvent>()
            .add_systems(
                Update,
                handle_attack_event
                    .before(update_bounding_box)
                    .before(MoveEventsSet)
                    .after(perform_respawn),
            )
            .add_systems(
                GameTick,
                (
                    increment_ticks_since_last_attack,
                    update_attack_strength_scale.after(PhysicsSet),
                )
                    .chain(),
            );
    }
}

impl Client {
    /// Attack the entity with the given id.
    pub fn attack(&mut self, entity_id: MinecraftEntityId) {
        self.ecs.lock().send_event(AttackEvent {
            entity: self.entity,
            target: entity_id,
        });
    }

    /// Whether the player has an attack cooldown.
    pub fn has_attack_cooldown(&self) -> bool {
        let Some(AttackStrengthScale(ticks_since_last_attack)) =
            self.get_component::<AttackStrengthScale>()
        else {
            // they don't even have an AttackStrengthScale so they probably can't attack
            // lmao, just return false
            return false;
        };
        ticks_since_last_attack < 1.0
    }
}

#[derive(Event)]
pub struct AttackEvent {
    pub entity: Entity,
    pub target: MinecraftEntityId,
}
pub fn handle_attack_event(
    mut events: EventReader<AttackEvent>,
    mut query: Query<(
        &LocalGameMode,
        &mut TicksSinceLastAttack,
        &mut Physics,
        &mut Sprinting,
        &mut ShiftKeyDown,
    )>,
    mut send_packet_events: EventWriter<SendPacketEvent>,
    mut swing_arm_event: EventWriter<SwingArmEvent>,
) {
    for event in events.read() {
        let (game_mode, mut ticks_since_last_attack, mut physics, mut sprinting, sneaking) =
            query.get_mut(event.entity).unwrap();

        swing_arm_event.send(SwingArmEvent {
            entity: event.entity,
        });
        send_packet_events.send(SendPacketEvent {
            entity: event.entity,
            packet: ServerboundInteractPacket {
                entity_id: *event.target,
                action: serverbound_interact_packet::ActionType::Attack,
                using_secondary_action: **sneaking,
            }
            .get(),
        });

        // we can't attack if we're in spectator mode but it still sends the attack
        // packet
        if game_mode.current == GameMode::Spectator {
            continue;
        };

        ticks_since_last_attack.0 = 0;

        physics.velocity = physics.velocity.multiply(0.6, 1.0, 0.6);
        **sprinting = false;
    }
}

#[derive(Default, Bundle)]
pub struct AttackBundle {
    pub ticks_since_last_attack: TicksSinceLastAttack,
    pub attack_strength_scale: AttackStrengthScale,
}

#[derive(Default, Component, Clone, Deref, DerefMut)]
pub struct TicksSinceLastAttack(pub u32);
pub fn increment_ticks_since_last_attack(mut query: Query<&mut TicksSinceLastAttack>) {
    for mut ticks_since_last_attack in query.iter_mut() {
        **ticks_since_last_attack += 1;
    }
}

#[derive(Default, Component, Clone, Deref, DerefMut)]
pub struct AttackStrengthScale(pub f32);
pub fn update_attack_strength_scale(
    mut query: Query<(&TicksSinceLastAttack, &Attributes, &mut AttackStrengthScale)>,
) {
    for (ticks_since_last_attack, attributes, mut attack_strength_scale) in query.iter_mut() {
        // look 0.5 ticks into the future because that's what vanilla does
        **attack_strength_scale =
            get_attack_strength_scale(ticks_since_last_attack.0, attributes, 0.5);
    }
}

/// Returns how long it takes for the attack cooldown to reset (in ticks).
pub fn get_attack_strength_delay(attributes: &Attributes) -> f32 {
    ((1. / attributes.attack_speed.calculate()) * 20.) as f32
}

pub fn get_attack_strength_scale(
    ticks_since_last_attack: u32,
    attributes: &Attributes,
    in_ticks: f32,
) -> f32 {
    let attack_strength_delay = get_attack_strength_delay(attributes);
    let attack_strength = (ticks_since_last_attack as f32 + in_ticks) / attack_strength_delay;
    attack_strength.clamp(0., 1.)
}