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|
pub mod command;
pub mod consts;
pub mod global_json;
pub mod json;
pub mod state;
use command::*;
use consts::*;
use pathfinding::prelude::*;
use state::*;
use std::cmp::Ordering;
pub fn choose_command(round: usize, state: &GameState) -> Command {
if round <= 100 {
choose_command_with_looking_forward_heuristic(state)
} else {
choose_command_with_astar(state)
}
}
#[derive(Debug, Clone)]
struct HeuristicLookaheadState {
moves: Vec<Command>,
events: GameStateUpdateEvents,
current_state: GameState,
}
fn choose_command_with_looking_forward_heuristic(state: &GameState) -> Command {
let depth = 3;
let mut states = vec![HeuristicLookaheadState {
moves: Vec::new(),
events: GameStateUpdateEvents::default(),
current_state: state.clone(),
}];
for _ in 0..depth {
states = states
.into_iter()
.flat_map(move |state| {
state
.current_state
.good_moves(0)
.into_iter()
.map(move |player_move| {
let mut state = state.clone();
state.moves.push(player_move);
state
.current_state
.update([player_move, Command::Accelerate], &mut state.events);
state
})
})
.collect();
}
states
.into_iter()
.max_by(|a, b| compare_events(&a.events, &b.events))
.unwrap()
.moves
.into_iter()
.next()
.unwrap()
}
fn compare_states(a: &GameState, b: &GameState) -> Ordering {
if a.status == GameStatus::PlayerOneWon && b.status == GameStatus::PlayerOneWon {
a.players[0].speed.cmp(&b.players[0].speed)
} else if a.status == GameStatus::PlayerOneWon {
Ordering::Greater
} else if b.status == GameStatus::PlayerOneWon {
Ordering::Less
} else {
let weighted_position_a = a.players[0].position.x + a.players[0].boosts * 2;
let weighted_position_b = b.players[0].position.x + b.players[0].boosts * 2;
weighted_position_a
.cmp(&weighted_position_b)
.then(a.players[0].speed.cmp(&b.players[0].speed))
.then(a.players[0].position.x.cmp(&b.players[0].position.x))
.then(a.players[0].boosts.cmp(&b.players[0].boosts))
}
}
fn compare_events(a: &GameStateUpdateEvents, b: &GameStateUpdateEvents) -> Ordering {
let a = &a.players[0];
let b = &b.players[0];
a.boosts_collected
.cmp(&b.boosts_collected)
.then(a.boosts_maintained.cmp(&b.boosts_maintained))
.then(a.distance_travelled.cmp(&b.distance_travelled))
.then(a.mud_hit.cmp(&b.mud_hit).reverse())
.then(a.boosts_used.cmp(&b.boosts_used).reverse())
}
fn choose_command_with_astar(state: &GameState) -> Command {
// TODO: Find all shortest paths, choose the one that has the
// highest end speed, or otherwise wins
shortest_path_first_command(state).unwrap_or(Command::Accelerate)
}
fn shortest_path_first_command(initial_state: &GameState) -> Option<Command> {
let shortest_path_states = astar(
initial_state,
|state| {
state
.good_moves(0)
.into_iter()
.filter(|player_move| *player_move != Command::UseOil)
.map(|player_move| {
let mut state = state.clone();
state.update(
[player_move, Command::Decelerate],
&mut GameStateUpdateEvents::default(),
);
(state, 1)
})
.collect::<Vec<_>>()
},
|state| (WIDTH - state.players[0].position.x) / SPEED_BOOST,
|state| state.status != GameStatus::Continue,
)
.unwrap();
shortest_path_states
.0
.iter()
.zip(shortest_path_states.0.iter().skip(1))
.map(|(state, next)| {
let player_move = state
.good_moves(0)
.into_iter()
.filter(|player_move| *player_move != Command::UseOil)
.find(|player_move| {
let mut state = state.clone();
state.update(
[*player_move, Command::Decelerate],
&mut GameStateUpdateEvents::default(),
);
state == *next
})
.unwrap();
player_move
})
.next()
}
|
