feat: add snapshot recording

src/snapshot.py

@@ -2,12 +2,15 @@ from __future__ import annotations
 
 import struct
 from dataclasses import dataclass, field
-from typing import Optional
+from typing import TYPE_CHECKING, Optional
 
 import numpy as np
 
 from src.vec import Vec
 
+if TYPE_CHECKING:
+    from src.car import Car
+
 
 def iter_unpack(format, data):
     nbr_bytes = struct.calcsize(format)
@@ -20,7 +23,8 @@ class Snapshot:
     position: Vec = field(default_factory=Vec)
     direction: Vec = field(default_factory=Vec)
     speed: float = 0
-    raycast_distances: list[float] | tuple[float, ...] = field(default_factory=list)
+    raycast_distances: list[float] | tuple[float, ...] = field(
+        default_factory=list)
     image: Optional[np.ndarray] = None
 
     def pack(self):
@@ -36,10 +40,12 @@ class Snapshot:
         )
 
         nbr_raycasts: int = len(self.raycast_distances)
-        data += struct.pack(f">B{nbr_raycasts}f", nbr_raycasts, *self.raycast_distances)
+        data += struct.pack(f">B{nbr_raycasts}f",
+                            nbr_raycasts, *self.raycast_distances)
 
         if self.image is not None:
-            data += struct.pack(">II", self.image.shape[0], self.image.shape[1])
+            data += struct.pack(">II",
+                                self.image.shape[0], self.image.shape[1])
             data += self.image.tobytes()
         else:
             data += struct.pack(">II", 0, 0)
@@ -72,3 +78,19 @@ class Snapshot:
             raycast_distances=raycast_distances,
             image=image,
         )
+
+    @staticmethod
+    def from_car(car: Car) -> Snapshot:
+        return Snapshot(
+            controls=(
+                car.forward,
+                car.backward,
+                car.left,
+                car.right
+            ),
+            position=car.pos.copy(),
+            direction=car.direction.copy(),
+            speed=car.speed,
+            raycast_distances=car.rays.copy(),
+            image=None
+        )