Avoid the use of stride tricks to make code more readable

pylinalg/misc.py

@@ -1,5 +1,4 @@
 import numpy as np
-from numpy.lib.stride_tricks import as_strided
 
 
 def aabb_to_sphere(aabb, /, *, out=None, dtype=None):
@@ -73,32 +72,25 @@ def aabb_transform(aabb, matrix, /, *, out=None, dtype=None):
  if out is None:
  out = np.empty_like(aabb, dtype=dtype)
 
- corners = np.empty((*aabb.shape[:-2], 8, 4), dtype=float)
- corners[...] = [1, 2, 3, 4]
- size = corners.itemsize
-
- corners_x = as_strided(
- corners[..., 0],
- shape=(*corners.shape[:-2], 4, 2),
- strides=(*corners.strides[:-2], 8 * size, 4 * size),
- )
- corners_x[:] = aabb[..., :, 0]
-
- corners_y = as_strided(
- corners[..., 1],
- shape=(*corners.shape[:-2], 2, 2, 2),
- strides=(*corners.strides[:-2], 16 * size, 4 * size, 8 * size),
+ corners = np.full(
+ aabb.shape[:-2] + (8, 4),
+ # Fill value of 1 is used for homogeneous coordinates.
+ fill_value=1.,
+ dtype=float,
  )
- corners_y[:] = aabb[..., :, 1]
-
- corners_z = as_strided(
- corners[..., 2],
- shape=(*corners.shape[:-2], 4, 2),
- strides=(*corners.strides[:-2], 4 * size, 16 * size),
- )
- corners_z[:] = aabb[..., :, 2]
-
- corners[..., 3] = 1
+ # x
+ corners[..., 0::2, 0] = aabb[..., 0, 0]
+ corners[..., 1::2, 0] = aabb[..., 1, 0]
+
+ # y
+ corners[..., 0::4, 1] = aabb[..., 0, 1]
+ corners[..., 1::4, 1] = aabb[..., 0, 1]
+ corners[..., 2::4, 1] = aabb[..., 1, 1]
+ corners[..., 3::4, 1] = aabb[..., 1, 1]
+
+ # z
+ corners[..., 0:4, 2] = aabb[..., 0, 2]
+ corners[..., 4:8, 2] = aabb[..., 1, 2]
 
  corners = corners @ matrix
  out[..., 0, :] = np.min(corners[..., :-1], axis=-2)