Fix intersection on bounds for rotated grids

Author: tmillenaar

gridkit-py/src/lib.rs

@@ -954,7 +954,7 @@ impl PyO3TriGrid {
     ) -> PyO3TriGrid {
         let target_loc: [f64; 2] = target_loc.into();
         let cell_element =
-            CellElement::from_string(&cell_element).expect("Unsupported cell_element {}");
+            CellElement::from_string(&cell_element).expect(&format!("Unsupported cell_element: '{}'", cell_element));
         let mut new_grid = self.clone();
         new_grid._grid.anchor_inplace(&target_loc, cell_element);
         new_grid
@@ -968,7 +968,7 @@ impl PyO3TriGrid {
     ) {
         let target_loc: [f64; 2] = target_loc.into();
         let cell_element =
-            CellElement::from_string(&cell_element).expect("Unsupported cell_element {}");
+            CellElement::from_string(&cell_element).expect(&format!("Unsupported cell_element: '{}'", cell_element));
         self._grid.anchor_inplace(&target_loc, cell_element);
     }
 
@@ -1145,7 +1145,7 @@ impl PyO3RectGrid {
     ) -> PyO3RectGrid {
         let target_loc: [f64; 2] = target_loc.into();
         let cell_element =
-            CellElement::from_string(&cell_element).expect("Unsupported cell_element {}");
+            CellElement::from_string(&cell_element).expect(&format!("Unsupported cell_element: '{}'", cell_element));
         let mut new_grid = self.clone();
         new_grid._grid.anchor_inplace(&target_loc, cell_element);
         new_grid
@@ -1159,7 +1159,7 @@ impl PyO3RectGrid {
     ) {
         let target_loc: [f64; 2] = target_loc.into();
         let cell_element =
-            CellElement::from_string(&cell_element).expect("Unsupported cell_element {}");
+            CellElement::from_string(&cell_element).expect(&format!("Unsupported cell_element: '{}'", cell_element));
         self._grid.anchor_inplace(&target_loc, cell_element);
     }
 

gridkit-py/tests/test_gridkit/test_statistical_functions.py

@@ -75,8 +75,9 @@ def test_combine_tiles(grid):
         HexGrid(size=1, shape="flat"),
     ],
 )
-def test_count_data_tile(grid):
-    grid.rotation = 12
+@pytest.mark.parametrize("rotation", [-12, 363, 186])
+def test_count_data_tile(grid, rotation):
+    grid.rotation = rotation
 
     tile1 = Tile(grid, (-2, -3), 5, 7)
     tile2 = Tile(grid, (1, 0), 7, 5).to_data_tile_with_value(3.2)

gridkit-rs/src/tile.rs

@@ -213,20 +213,35 @@ impl TileTraits for Tile {
     }
 
     fn intersects(&self, other: &Tile) -> bool {
+
+        // Note: It is easier to match tiles on their ids. This seems elegant
+        //       because we don't need to care about rotation. This was how it
+        //       was first implemented but it required self and other to be on
+        //       the same grid. This was not enforced so you would get weird
+        //       results if this was not upheld. Rather than forcing the grids
+        //       to be aligned we use the tile corner coordinates. This way
+        //       any tile can be checked for intersection with any other tile
+        //       purely based on location, regardless of the host grid. This
+        //       does have the downside that we need to account for rotated
+        //       grids where the corner that was originally the on the left
+        //       side might now be the rightmost corner.
         let corners_self = self.corners();
         let corners_other = other.corners();
 
-        let left_self = corners_self[Ix2(3,0)];
-        let bottom_self = corners_self[Ix2(3,1)];
-        let right_self = corners_self[Ix2(1,0)];
-        let top_self = corners_self[Ix2(1,1)];
-
-        let left_other = corners_other[Ix2(3,0)];
-        let bottom_other = corners_other[Ix2(3,1)];
-        let right_other = corners_other[Ix2(1,0)];
-        let top_other = corners_other[Ix2(1,1)];
-        return !(
-               left_self   >= right_other
+        // Get min and max values.
+        // Note: This is a thorn in the eye as .min() does not work
+        //       on ndarrays of dtype float because of nan and inf values.
+        let left_self = corners_self.slice(s![..,0]).iter().cloned().reduce(f64::min).unwrap();
+        let bottom_self = corners_self.slice(s![..,1]).iter().cloned().reduce(f64::min).unwrap();
+        let right_self = corners_self.slice(s![..,0]).iter().cloned().reduce(f64::max).unwrap();
+        let top_self = corners_self.slice(s![..,1]).iter().cloned().reduce(f64::max).unwrap();
+
+        let left_other = corners_other.slice(s![..,0]).iter().cloned().reduce(f64::min).unwrap();
+        let bottom_other = corners_other.slice(s![..,1]).iter().cloned().reduce(f64::min).unwrap();
+        let right_other = corners_other.slice(s![..,0]).iter().cloned().reduce(f64::max).unwrap();
+        let top_other = corners_other.slice(s![..,1]).iter().cloned().reduce(f64::max).unwrap();
+
+        return !(left_self   >= right_other
             || right_self  <= left_other
             || bottom_self >= top_other
             || top_self    <= bottom_other