feat: initial implementation of image capture

.gitignore

@@ -9,4 +9,7 @@ wheels/
 # Virtual environments
 .venv
 
-.vscode
+.vscode
+
+records
+*.rec

README.md

@@ -0,0 +1,59 @@
+<p align="center">
+    <img src="logo.png" width="300">
+</p>
+
+# Rally Racer
+
+This repository holds a sandbox driving simulation controllable via a network interface as a machine learning and data collection challenge.
+
+# Installation
+From the root of the repository, run
+```sh
+uv sync
+```
+
+To run the game, you can use
+```sh
+uv run main.py
+```
+
+# Generality
+Launching [`main.py`](main.py) starts a race with a single car on the provided track. 
+This track can be controlled either by keyboard (*WASD*) or by a socket interface. 
+An example of such interface is included in the code in [*`scripts/recorder.py`*](scripts/recorder.py). To run it, simply use the following command:
+```sh
+uv run -m scripts.recorder
+```
+
+# Sensing
+The car sensing is available in two commodities: **raycasts** and **images**. These sensing snapshots are sent at 10 Hertz (i.e. 10 times a second). Due to this fact, correct reception of snapshot messages has to be done regularly.
+
+# Communication protocol
+
+A remote controller can be impemented using TCP socket connecting on localhost on port 5000.
+Different commands can be issued to the race simulation to control the car.
+
+These commands are declared in [`src/command.py`](src/command.py)
+
+##  Car controls
+```python
+ControlCommand(control: CarControl, active: bool)
+```
+To simulate key press and control the car.
+
+
+# Controls
+
+- <kbd>W</kbd> Move forward
+- <kbd>S</kbd> Brake / move backward
+- <kbd>A</kbd> Turn left
+- <kbd>D</kbd> Turn right
+- <kbd>F</kbd> Toggle FPS indicator
+- <kbd>V</kbd> Toggle speedometer
+- <kbd>R</kbd> Reset car
+- <kbd>C</kbd> Toggle raycasts visibility
+- <kbd>Esc</kbd> Quit
+
+
+# Credits
+This project is based on the repository [https://github.com/ISC-HEI/RallyRobotPilot_2025](https://github.com/ISC-HEI/RallyRobotPilot_2025), which is in turn based on [https://github.com/mandaw2014/Rally](https://github.com/mandaw2014/Rally)

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logo.svg

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scripts/example_bot.py

@@ -0,0 +1,41 @@
+from PyQt6.QtWidgets import QApplication
+
+from src.bot import Bot
+from src.command import CarControl
+from src.recorder import RecorderWindow
+from src.snapshot import Snapshot
+
+
+class ExampleBot(Bot):
+    def nn_infer(self, snapshot: Snapshot) -> list[tuple[CarControl, bool]]:
+        #   Do smart NN inference here
+        return [(CarControl.FORWARD, True)]
+
+    def on_snapshot_received(self, snapshot: Snapshot):
+        controls: list[tuple[CarControl, bool]] = self.nn_infer(snapshot)
+        for control, active in controls:
+            self.recorder.on_car_controlled(control, active)
+
+
+def main():
+    import sys
+
+    def except_hook(cls, exception, traceback):
+        sys.__excepthook__(cls, exception, traceback)
+
+    sys.excepthook = except_hook
+
+    app: QApplication = QApplication(sys.argv)
+    recorder: RecorderWindow = RecorderWindow("localhost", 5000)
+    bot: ExampleBot = ExampleBot()
+    bot.set_recorder(recorder)
+
+    app.aboutToQuit.connect(recorder.shutdown)
+    recorder.register_bot(bot)
+    recorder.show()
+
+    app.exec()
+
+
+if __name__ == "__main__":
+    main()

src/bot.py

@@ -0,0 +1,26 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Optional
+
+from src.snapshot import Snapshot
+
+if TYPE_CHECKING:
+    from src.recorder import RecorderWindow
+
+
+class Bot:
+    def __init__(self):
+        self._recorder: Optional[RecorderWindow] = None
+
+    @property
+    def recorder(self) -> RecorderWindow:
+        if self._recorder is None:
+            raise RuntimeError(
+                "Bot does not have a recorder. Call Bot.set_recorder to set one")
+        return self._recorder
+
+    def set_recorder(self, recorder: RecorderWindow):
+        self._recorder = recorder
+
+    def on_snapshot_received(self, snapshot: Snapshot):
+        pass

src/car.py

@@ -1,5 +1,7 @@
+from __future__ import annotations
+
 from math import radians
-from typing import Optional
+from typing import TYPE_CHECKING, Optional
 
 import pygame
 
@@ -8,7 +10,11 @@ from src.remote_controller import RemoteController
 from src.utils import get_segments_intersection, segments_intersect
 from src.vec import Vec
 
-sign = lambda x: 0 if x == 0 else (-1 if x < 0 else 1)
+if TYPE_CHECKING:
+    from src.game import Game
+
+
+def sign(x): return 0 if x == 0 else (-1 if x < 0 else 1)
 
 
 class Car:
@@ -26,7 +32,10 @@ class Car:
     RAYS_FOV = 180
     RAYS_MAX_DIST = 100
 
-    def __init__(self, pos: Vec, direction: Vec) -> None:
+    def __init__(self, game: Game, pos: Vec, direction: Vec) -> None:
+        self.game: Game = game
+        self.initial_pos: Vec = pos.copy()
+        self.initial_dir: Vec = direction.copy()
         self.pos: Vec = pos
         self.direction: Vec = direction
         self.speed: float = 0
@@ -39,7 +48,7 @@ class Car:
         self.rays: list[float] = [0] * self.N_RAYS
         self.rays_end: list[Vec] = [Vec() for _ in range(self.N_RAYS)]
 
-        self.controller: RemoteController = RemoteController(self)
+        self.controller: RemoteController = RemoteController(self.game, self)
         self.controller.start_server()
 
     def update(self, dt: float):
@@ -77,7 +86,8 @@ class Car:
         if show_raycasts:
             pos: Vec = camera.world2screen(self.pos)
             for p in self.rays_end:
-                pygame.draw.line(surf, (255, 0, 0), pos, camera.world2screen(p), 2)
+                pygame.draw.line(surf, (255, 0, 0), pos,
+                                 camera.world2screen(p), 2)
 
         pts: list[Vec] = self.get_corners()
         pts = [camera.world2screen(p) for p in pts]
@@ -127,14 +137,17 @@ class Car:
                             n *= -1
                             dist = -dist
                         self.speed = 0
-                        self.pos = self.pos + n * (self.COLLISION_MARGIN - dist)
+                        self.pos = self.pos + n * \
+                            (self.COLLISION_MARGIN - dist)
                         return
 
     def cast_rays(self, polygons: list[list[Vec]]):
         for i in range(self.N_RAYS):
-            angle: float = radians((i / (self.N_RAYS - 1) - 0.5) * self.RAYS_FOV)
+            angle: float = radians(
+                (i / (self.N_RAYS - 1) - 0.5) * self.RAYS_FOV)
             p: Optional[Vec] = self.cast_ray(angle, polygons)
-            self.rays[i] = self.RAYS_MAX_DIST if p is None else (p - self.pos).mag()
+            self.rays[i] = self.RAYS_MAX_DIST if p is None else (
+                p - self.pos).mag()
             self.rays_end[i] = self.pos if p is None else p
 
     def cast_ray(self, angle: float, polygons: list[list[Vec]]) -> Optional[Vec]:
@@ -161,3 +174,8 @@ class Car:
                     dist = d
                     closest = p
         return closest
+
+    def reset(self):
+        self.pos = self.initial_pos.copy()
+        self.direction = self.initial_dir.copy()
+        self.speed = 0

src/command.py

@@ -5,10 +5,14 @@ from enum import IntEnum
 import struct
 from typing import Type
 
+from src.snapshot import Snapshot
+
 
 class CommandType(IntEnum):
     CAR_CONTROL = 0
     RECORDING = 1
+    APPLY_SNAPSHOT = 2
+    RESET = 3
 
 
 class CarControl(IntEnum):
@@ -30,8 +34,8 @@ class Command(abc.ABC):
             )
         Command.REGISTRY[cls.TYPE] = cls
 
-    @abc.abstractmethod
+    def get_payload(self) -> bytes:
-    def get_payload(self) -> bytes: ...
+        return b""
 
     def pack(self) -> bytes:
         payload: bytes = self.get_payload()
@@ -43,8 +47,8 @@ class Command(abc.ABC):
         return Command.REGISTRY[type].from_payload(data[1:])
 
     @classmethod
-    @abc.abstractmethod
+    def from_payload(cls, payload: bytes) -> Command:
-    def from_payload(cls, payload: bytes) -> Command: ...
+        return cls()
 
 
 class ControlCommand(Command):
@@ -82,3 +86,24 @@ class RecordingCommand(Command):
     def from_payload(cls, payload: bytes) -> Command:
         state: bool = struct.unpack(">B", payload)[0]
         return RecordingCommand(state)
+
+
+class ApplySnapshotCommand(Command):
+    TYPE = CommandType.APPLY_SNAPSHOT
+    __match_args__ = ("snapshot",)
+
+    def __init__(self, snapshot: Snapshot) -> None:
+        super().__init__()
+        self.snapshot: Snapshot = snapshot
+
+    def get_payload(self) -> bytes:
+        return self.snapshot.pack()
+
+    @classmethod
+    def from_payload(cls, payload: bytes) -> Command:
+        snapshot: Snapshot = Snapshot.unpack(payload)
+        return ApplySnapshotCommand(snapshot)
+
+
+class ResetCommand(Command):
+    TYPE = CommandType.RESET

src/game.py

@@ -19,10 +19,11 @@ class Game:
         self.win: pygame.Surface = pygame.display.set_mode(
             self.DEFAULT_SIZE, pygame.RESIZABLE
         )
+        self.game_surf: pygame.Surface = pygame.Surface(self.DEFAULT_SIZE)
         pygame.display.set_caption("Rally Racer")
         self.running: bool = True
         self.track: Track = Track.load("simple")
-        self.car: Car = Car(self.track.start_pos, self.track.start_dir)
+        self.car: Car = Car(self, self.track.start_pos, self.track.start_dir)
         self.camera: Camera = Camera()
 
         self.clock: pygame.time.Clock = pygame.time.Clock()
@@ -49,6 +50,7 @@ class Game:
             if event.type == pygame.QUIT:
                 self.quit()
             elif event.type == pygame.VIDEORESIZE:
+                self.game_surf = pygame.Surface((event.w, event.h))
                 self.camera.set_size(Vec(event.w, event.h))
             elif event.type == pygame.KEYDOWN:
                 if event.key == pygame.K_ESCAPE:
@@ -68,9 +70,10 @@ class Game:
         self.car.controller.close()
 
     def render(self):
-        self.win.fill(self.BACKGROUND_COLOR)
+        self.game_surf.fill(self.BACKGROUND_COLOR)
-        self.track.render(self.win, self.camera)
+        self.track.render(self.game_surf, self.camera)
-        self.car.render(self.win, self.camera, self.show_raycasts)
+        self.car.render(self.game_surf, self.camera, self.show_raycasts)
+        self.win.blit(self.game_surf, (0, 0))
         if self.show_fps:
             self.render_fps()
         if self.show_speed:

src/record_file.py

@@ -1,3 +1,4 @@
+import lzma
 from pathlib import Path
 import struct
 import time
@@ -12,7 +13,7 @@ class RecordFile:
     def __init__(self, path: str | Path, mode: Literal["w", "r"]) -> None:
         self.path: str | Path = path
         self.mode: Literal["w", "r"] = mode
-        self.file = open(self.path, self.mode + "b")
+        self.file: lzma.LZMAFile = lzma.LZMAFile(self.path, self.mode)
 
     def __enter__(self):
         return self
@@ -21,8 +22,7 @@ class RecordFile:
         self.file.close()
 
     def write_header(self, n_snapshots: int):
-        data: bytes = struct.pack(
+        data: bytes = struct.pack(">IId", self.VERSION, n_snapshots, time.time())
-            ">IId", self.VERSION, n_snapshots, time.time())
         self.file.write(data)
 
     def write_snapshots(self, snapshots: list[Snapshot]):
@@ -35,7 +35,8 @@ class RecordFile:
         version: int = struct.unpack(">I", self.file.read(4))[0]
         if version != self.VERSION:
             raise ValueError(
-                f"Cannot parse record file with format version {version} (current version: {self.VERSION})")
+                f"Cannot parse record file with format version {version} (current version: {self.VERSION})"
+            )
 
         n_snapshots: int
         timestamp: float

src/recorder.py

@@ -9,14 +9,15 @@ from PyQt6.QtCore import QObject, QThread, QTimer, pyqtSignal, pyqtSlot
 from PyQt6.QtGui import QKeyEvent
 from PyQt6.QtWidgets import QMainWindow
 
-from src.command import CarControl, Command, ControlCommand, RecordingCommand
+from src.bot import Bot
+from src.command import ApplySnapshotCommand, CarControl, Command, ControlCommand, RecordingCommand, ResetCommand
 from src.record_file import RecordFile
 from src.recorder_ui import Ui_Recorder
 from src.snapshot import Snapshot
 
 
 class RecorderClient(QObject):
-    DATA_CHUNK_SIZE = 4096
+    DATA_CHUNK_SIZE = 65536
     data_received: pyqtSignal = pyqtSignal(Snapshot)
 
     def __init__(self, host: str, port: int) -> None:
@@ -27,6 +28,7 @@ class RecorderClient(QObject):
             socket.AF_INET, socket.SOCK_STREAM)
         self.timer: Optional[QTimer] = None
         self.connected: bool = False
+        self.buffer: bytes = b""
 
     @pyqtSlot()
     def start(self):
@@ -39,27 +41,27 @@ class RecorderClient(QObject):
         print("Connected to server")
 
     def poll_socket(self):
-        buffer: bytes = b""
         if not self.connected:
             return
 
         try:
-            chunk: bytes = self.socket.recv(self.DATA_CHUNK_SIZE)
-            if not chunk:
-                return
-            buffer += chunk
-
             while True:
-                if len(buffer) < 4:
+                chunk: bytes = self.socket.recv(self.DATA_CHUNK_SIZE)
-                    break
+                if not chunk:
-                msg_len: int = struct.unpack(">I", buffer[:4])[0]
+                    return
-                msg_end: int = 4 + msg_len
+                self.buffer += chunk
-                if len(buffer) < msg_end:
-                    break
 
-                message: bytes = buffer[4:msg_end]
+                while True:
-                buffer = buffer[msg_end:]
+                    if len(self.buffer) < 4:
-                self.on_message(message)
+                        break
+                    msg_len: int = struct.unpack(">I", self.buffer[:4])[0]
+                    msg_end: int = 4 + msg_len
+                    if len(self.buffer) < msg_end:
+                        break
+
+                    message: bytes = self.buffer[4:msg_end]
+                    self.buffer = self.buffer[msg_end:]
+                    self.on_message(message)
         except BlockingIOError:
             pass
         except Exception as e:
@@ -162,9 +164,11 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
         self.recordDataButton.clicked.connect(self.toggle_record)
         self.resetButton.clicked.connect(self.rollback)
 
+        self.bot: Optional[Bot] = None
         self.autopiloting = False
 
         self.autopilotButton.clicked.connect(self.toggle_autopilot)
+        self.autopilotButton.setDisabled(True)
 
         self.saveRecordButton.clicked.connect(self.save_record)
 
@@ -203,7 +207,19 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
         self.send_command(RecordingCommand(self.recording))
 
     def rollback(self):
-        pass
+        rollback_by: int = self.forgetSnapshotNumber.value()
+        rollback_by = max(0, min(rollback_by, len(self.snapshots) - 1))
+
+        self.snapshots = self.snapshots[:-rollback_by]
+        self.nbrSnapshotSaved.setText(str(len(self.snapshots)))
+
+        if len(self.snapshots) == 0:
+            self.send_command(ResetCommand())
+        else:
+            self.send_command(ApplySnapshotCommand(self.snapshots[-1]))
+
+        if self.recording:
+            self.toggle_record()
 
     def toggle_autopilot(self):
         self.autopiloting = not self.autopiloting
@@ -227,7 +243,7 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
 
         self.SAVE_DIR.mkdir(exist_ok=True)
 
-        record_name: str = "record_%d.rec"
+        record_name: str = "record_%d.rec.xz"
         fid = 0
         while os.path.exists(self.SAVE_DIR / (record_name % fid)):
             fid += 1
@@ -251,8 +267,15 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
         self.snapshots.append(snapshot)
         self.nbrSnapshotSaved.setText(str(len(self.snapshots)))
 
+        if self.autopiloting and self.bot is not None:
+            self.bot.on_snapshot_received(snapshot)
+
     def shutdown(self):
         self.close_signal.emit()
 
     def send_command(self, command: Command):
         self.send_signal.emit(command)
+
+    def register_bot(self, bot: Bot):
+        self.bot = bot
+        self.autopilotButton.setDisabled(False)

src/recorder.ui

@@ -99,7 +99,7 @@
       <item>
        <widget class="QPushButton" name="resetButton">
         <property name="text">
-         <string>Reset</string>
+         <string>Rollback</string>
         </property>
        </widget>
       </item>

src/recorder_ui.py

@@ -1,6 +1,6 @@
 # Form implementation generated from reading ui file 'recorder.ui'
 #
-# Created by: PyQt6 UI code generator 6.8.0
+# Created by: PyQt6 UI code generator 6.8.1
 #
 # WARNING: Any manual changes made to this file will be lost when pyuic6 is
 # run again.  Do not edit this file unless you know what you are doing.
@@ -102,7 +102,7 @@ class Ui_Recorder(object):
         self.recordDataButton.setText(_translate("Recorder", "Record"))
         self.saveImgCheckBox.setText(_translate("Recorder", "Imgs"))
         self.saveRecordButton.setText(_translate("Recorder", "Save"))
-        self.resetButton.setText(_translate("Recorder", "Reset"))
+        self.resetButton.setText(_translate("Recorder", "Rollback"))
         self.nbrSnapshotSaved.setText(_translate("Recorder", "0"))
         self.autopilotButton.setText(_translate("Recorder", "AutoPilot\n"
 "OFF"))

src/remote_controller.py

@@ -6,17 +6,18 @@ import struct
 import threading
 from typing import TYPE_CHECKING, Optional
 
-from src.command import CarControl, Command, ControlCommand, RecordingCommand
+from src.command import ApplySnapshotCommand, CarControl, Command, ControlCommand, RecordingCommand, ResetCommand
 from src.snapshot import Snapshot
 from src.utils import RepeatTimer
 
 if TYPE_CHECKING:
     from src.car import Car
+    from src.game import Game
 
 
 class RemoteController:
     DEFAULT_PORT = 5000
-    DATA_CHUNK_SIZE = 4096
+    DATA_CHUNK_SIZE = 65536
 
     CONTROL_ATTRIBUTES: dict[CarControl, str] = {
         CarControl.FORWARD: "forward",
@@ -27,7 +28,8 @@ class RemoteController:
 
     SNAPSHOT_INTERVAL = 0.1
 
-    def __init__(self, car: Car, port: int = DEFAULT_PORT) -> None:
+    def __init__(self, game: Game, car: Car, port: int = DEFAULT_PORT) -> None:
+        self.game: Game = game
         self.car: Car = car
         self.port: int = port
         self.server: socket.socket = socket.socket(
@@ -119,6 +121,10 @@ class RemoteController:
                 self.set_control(control, active)
             case RecordingCommand(state):
                 self.recording = state
+            case ApplySnapshotCommand(snapshot):
+                snapshot.apply(self.car)
+            case ResetCommand():
+                self.car.reset()
 
     def set_control(self, control: CarControl, active: bool):
         setattr(self.car, self.CONTROL_ATTRIBUTES[control], active)
@@ -130,5 +136,6 @@ class RemoteController:
             return
 
         snapshot: Snapshot = Snapshot.from_car(self.car)
+        snapshot.add_image(self.game)
         payload: bytes = snapshot.pack()
         self.client.sendall(struct.pack(">I", len(payload)) + payload)

src/snapshot.py

@@ -5,11 +5,13 @@ from dataclasses import dataclass, field
 from typing import TYPE_CHECKING, Optional
 
 import numpy as np
+import pygame
 
 from src.vec import Vec
 
 if TYPE_CHECKING:
     from src.car import Car
+    from src.game import Game
 
 
 def iter_unpack(format, data):
@@ -63,7 +65,7 @@ class Snapshot:
         (nbr_raycasts,), data = iter_unpack(">B", data)
         raycast_distances, data = iter_unpack(f">{nbr_raycasts}f", data)
 
-        (h, w), data = iter_unpack(">ii", data)
+        (h, w), data = iter_unpack(">II", data)
 
         if h * w > 0:
             image = np.frombuffer(data, np.uint8).reshape(h, w, 3)
@@ -94,3 +96,11 @@ class Snapshot:
             raycast_distances=car.rays.copy(),
             image=None
         )
+
+    def apply(self, car: Car):
+        car.pos = self.position.copy()
+        car.direction = self.direction.copy()
+        car.speed = 0
+
+    def add_image(self, game: Game):
+        self.image = pygame.surfarray.array3d(game.game_surf)