+ while True:
+ di, dj = torch.randint(7, (2,)) - 3
+ i, j = torch.randint(self.height, (1,)), torch.randint(self.width, (1,))
+ if (
+ abs(di) + abs(dj) > 0
+ and i + 2 * di >= 0
+ and i + 2 * di < self.height
+ and j + 2 * dj >= 0
+ and j + 2 * dj < self.width
+ ):
+ break
+
+ k = 0
+ while (
+ i + k * di >= 0
+ and i + k * di < self.height
+ and j + k * dj >= 0
+ and j + k * dj < self.width
+ ):
+ if k < 2:
+ X[i + k * di, j + k * dj] = c[k]
+ f_X[i + k * di, j + k * dj] = c[min(k, 1)]
+ k += 1
+
+ def task_bounce(self, A, f_A, B, f_B):
+ c = torch.randperm(len(self.colors) - 1)[:3] + 1
+ for X, f_X in [(A, f_A), (B, f_B)]:
+
+ def free(i, j):
+ return (
+ i >= 0
+ and i < self.height
+ and j >= 0
+ and j < self.width
+ and f_X[i, j] == 0
+ )
+
+ while True:
+ f_X[...] = 0
+ X[...] = 0
+
+ for _ in range((self.height * self.width) // 10):
+ i, j = torch.randint(self.height, (1,)), torch.randint(
+ self.width, (1,)
+ )
+ X[i, j] = c[0]
+ f_X[i, j] = c[0]
+
+ while True:
+ di, dj = torch.randint(7, (2,)) - 3
+ if abs(di) + abs(dj) == 1:
+ break
+
+ i, j = torch.randint(self.height, (1,)), torch.randint(self.width, (1,))
+
+ X[i, j] = c[1]
+ f_X[i, j] = c[1]
+ l = 0
+
+ while True:
+ l += 1
+ if free(i + di, j + dj):
+ pass
+ elif free(i - dj, j + di):
+ di, dj = -dj, di
+ if free(i + dj, j - di):
+ if torch.rand(1) < 0.5:
+ di, dj = -di, -dj
+ elif free(i + dj, j - di):
+ di, dj = dj, -di
+ else:
+ break
+
+ i, j = i + di, j + dj
+ f_X[i, j] = c[2]
+ if l <= 1:
+ X[i, j] = c[2]
+
+ if l >= self.width:
+ break
+
+ f_X[i, j] = c[1]
+ X[i, j] = c[1]
+
+ if l > 3:
+ break