From c1266274f60a5429d0cf4e77f0c2c2d6c91d9902 Mon Sep 17 00:00:00 2001
From: Richard <richard@rghsoftware.co.uk>
Date: Mon, 11 Nov 2024 16:16:40 +0000
Subject: [PATCH] ensure grid is properly tiled

---
 .../triangles/abstract_coordinate_array.py     | 17 ++++++-----------
 .../test_coordinate_implementation.py          | 18 ++++++++++++++++++
 2 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/autoarray/structures/triangles/abstract_coordinate_array.py b/autoarray/structures/triangles/abstract_coordinate_array.py
index 0b831698..72267275 100644
--- a/autoarray/structures/triangles/abstract_coordinate_array.py
+++ b/autoarray/structures/triangles/abstract_coordinate_array.py
@@ -140,23 +140,18 @@ def for_limits_and_scale(
         scale: float = 1.0,
         **_,
     ):
+        x_shift = int(2 * x_min / scale)
+        y_shift = int(y_min / (HEIGHT_FACTOR * scale))
+
         coordinates = []
-        x = x_min
-        while x < x_max:
-            y = y_min
-            while y < y_max:
-                coordinates.append([x, y])
-                y += scale
-            x += scale
 
-        x_mean = (x_min + x_max) / 2
-        y_mean = (y_min + y_max) / 2
+        for x in range(x_shift, int(2 * x_max / scale) + 1):
+            for y in range(y_shift - 1, int(y_max / (HEIGHT_FACTOR * scale)) + 2):
+                coordinates.append([x, y])
 
         return cls(
             coordinates=np.array(coordinates),
             side_length=scale,
-            x_offset=x_mean,
-            y_offset=y_mean,
         )
 
     @property
diff --git a/test_autoarray/structures/triangles/test_coordinate_implementation.py b/test_autoarray/structures/triangles/test_coordinate_implementation.py
index 3e495de0..96b040b2 100644
--- a/test_autoarray/structures/triangles/test_coordinate_implementation.py
+++ b/test_autoarray/structures/triangles/test_coordinate_implementation.py
@@ -296,3 +296,21 @@ def test_triangles_touch():
         np.array([[0, 0], [0, 1]]),
     )
     assert max(triangles.triangles[0][:, 1]) == min(triangles.triangles[1][:, 1])
+
+
+def test_from_grid_regression():
+    triangles = CoordinateArrayTriangles.for_limits_and_scale(
+        x_min=-4.75,
+        x_max=4.75,
+        y_min=-4.75,
+        y_max=4.75,
+        scale=0.5,
+    )
+
+    x = triangles.vertices[:, 0]
+    assert min(x) <= -4.75
+    assert max(x) >= 4.75
+
+    y = triangles.vertices[:, 1]
+    assert min(y) <= -4.75
+    assert max(y) >= 4.75