Limit thickness of circular sectors to within a grid

gprMax/user_inputs.py

@@ -211,6 +211,53 @@ class MainGridUserInput(UserInput[GridType]):
             p3_checked,
         )
 
+    def check_thickness(
+        self, dimension: str, start: float, thickness: float
+    ) -> Tuple[bool, float, float]:
+        """Check the thickness of an object in a specified dimension.
+
+        Args:
+            dimension: Dimension to check the thickness value for.
+                This must have value x, y, or z.
+            start: Start coordinate of the object in the specified
+                dimension. This must be in the local grid coordinate
+                system - i.e. previously translated using the
+                round_to_grid function.
+            thickness: Thickness of the object.
+
+        Raises:
+            ValueError: Raised if dimension has an invalid value.
+
+        Returns:
+            within_grid: True if part of the object is within the
+                current grid. False otherwise.
+            start: Start value limited to the bounds of the grid.
+            thickness: Thickness value such that start + thickness is
+                within the bounds of the grid.
+        """
+        if dimension == "x":
+            grid_size = self.grid.nx * self.grid.dx
+        elif dimension == "y":
+            grid_size = self.grid.ny * self.grid.dy
+        elif dimension == "z":
+            grid_size = self.grid.nz * self.grid.dz
+        else:
+            raise ValueError("Dimension should have value x, y, or z")
+
+        end = start + thickness
+
+        if start > grid_size:
+            return False, start, thickness
+        elif end < 0:
+            return False, start, thickness
+
+        if start < 0:
+            start = 0
+        if end > grid_size:
+            thickness = grid_size - start
+
+        return True, start, thickness
+
 
 class MPIUserInput(MainGridUserInput[MPIGrid]):
     """Handles (x, y, z) points supplied by the user for MPI grids.

gprMax/user_objects/cmds_geometry/cylindrical_sector.py

@@ -74,6 +74,29 @@ class CylindricalSector(GeometryUserObject):
             logger.exception(self.__str__())
             raise
 
+        # Check thickness of the object first as may be able to exit
+        # early if fully outside the grid.
+        uip = self._create_uip(grid)
+
+        # yz-plane cylindrical sector
+        if normal == "x":
+            level, ctr1, ctr2 = uip.round_to_grid((extent1, ctr1, ctr2))
+
+        # xz-plane cylindrical sector
+        elif normal == "y":
+            ctr1, level, ctr2 = uip.round_to_grid((ctr1, extent1, ctr2))
+
+        # xy-plane cylindrical sector
+        elif normal == "z":
+            ctr1, ctr2, level = uip.round_to_grid((ctr1, ctr2, extent1))
+
+        sector_within_grid, level, thickness = uip.check_thickness(normal, level, thickness)
+
+        # Exit early if none of the cylindrical sector is in this grid
+        # as there is nothing else to do.
+        if not sector_within_grid:
+            return
+
         # Check averaging
         try:
             # Try user-specified averaging
@@ -162,19 +185,6 @@ class CylindricalSector(GeometryUserObject):
                 numIDy = materials[1].numID
                 numIDz = materials[2].numID
 
-        uip = self._create_uip(grid)
-        # yz-plane cylindrical sector
-        if normal == "x":
-            level, ctr1, ctr2 = uip.round_to_grid((extent1, ctr1, ctr2))
-
-        # xz-plane cylindrical sector
-        elif normal == "y":
-            ctr1, level, ctr2 = uip.round_to_grid((ctr1, extent1, ctr2))
-
-        # xy-plane cylindrical sector
-        elif normal == "z":
-            ctr1, ctr2, level = uip.round_to_grid((ctr1, ctr2, extent1))
-
         build_cylindrical_sector(
             ctr1,
             ctr2,