python: add some initial automesh features

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>

python/Tutorials/Simple_Patch_Antenna.py

@@ -58,7 +58,7 @@ mesh_res = C0/(f0+fc)/1e-3/20
 
 ### Generate properties, primitives and mesh-grid
 #initialize the mesh with the "air-box" dimensions
-mesh.AddLine('x', [-SimBox[0]/2, feed_pos, SimBox[0]/2])
+mesh.AddLine('x', [-SimBox[0]/2, SimBox[0]/2])
 mesh.AddLine('y', [-SimBox[1]/2, SimBox[1]/2]          )
 mesh.AddLine('z', [-SimBox[2]/3, SimBox[2]*2/3]        )
 
@@ -66,14 +66,14 @@ mesh.AddLine('z', [-SimBox[2]/3, SimBox[2]*2/3]        )
 patch = CSX.AddMetal( 'patch' ) # create a perfect electric conductor (PEC)
 start = [-patch_width/2, -patch_length/2, substrate_thickness]
 stop  = [ patch_width/2 , patch_length/2, substrate_thickness]
-pb=patch.AddBox(priority=10, start=start, stop=stop) # add a box-primitive to the metal property 'patch'
-pb.AddEdges2Grid('xy', metal_edge_res=mesh_res/2)
+patch.AddBox(priority=10, start=start, stop=stop) # add a box-primitive to the metal property 'patch'
+FDTD.AddEdges2Grid(dirs='xy', properties=patch, metal_edge_res=mesh_res/2)
 
 # create substrate
 substrate = CSX.AddMaterial( 'substrate', epsilon=substrate_epsR, kappa=substrate_kappa)
 start = [-substrate_width/2, -substrate_length/2, 0]
 stop  = [ substrate_width/2,  substrate_length/2, substrate_thickness]
-sb=substrate.AddBox( priority=0, start=start, stop=stop )
+substrate.AddBox( priority=0, start=start, stop=stop )
 
 # add extra cells to discretize the substrate thickness
 mesh.AddLine('z', linspace(0,substrate_thickness,substrate_cells+1))
@@ -82,12 +82,14 @@ mesh.AddLine('z', linspace(0,substrate_thickness,substrate_cells+1))
 gnd = CSX.AddMetal( 'gnd' ) # create a perfect electric conductor (PEC)
 start[2]=0
 stop[2] =0
-gb=gnd.AddBox(start, stop, priority=10, edges2grid='all')
+gnd.AddBox(start, stop, priority=10)
+
+FDTD.AddEdges2Grid(dirs='xy', properties=gnd)
 
 # apply the excitation & resist as a current source
 start = [feed_pos, 0, 0]
 stop  = [feed_pos, 0, substrate_thickness]
-port = FDTD.AddLumpedPort(1 ,feed_R, start, stop, 'z', 1.0, priority=5, edges2grid='all')
+port = FDTD.AddLumpedPort(1, feed_R, start, stop, 'z', 1.0, priority=5, edges2grid='xy')
 
 mesh.SmoothMeshLines('all', mesh_res, 1.4)
 

python/openEMS/automesh.py

@@ -0,0 +1,77 @@
+# -*- coding: utf-8 -*-
+"""
+Created on Sun Feb 19 20:29:25 2017
+
+@author: thorsten
+"""
+
+import sys
+import numpy as np
+
+from CSXCAD import CSPrimitives
+from CSXCAD.Utilities import CheckNyDir, GetMultiDirs
+
+def mesh_hint_from_primitive(primitive, dirs, **kw):
+    if primitive.GetType() is CSPrimitives.POINT:
+        return mesh_hint_from_point(primitive, dirs, **kw)
+    if primitive.GetType() is CSPrimitives.BOX:
+        return mesh_hint_from_box(primitive, dirs, **kw)
+    else:
+        return None
+
+def mesh_hint_from_point(point, dirs, **kw):
+    """ mesh_hint_from_point(point, dirs)
+
+    Get a grid hint for the coordinates of the point.
+
+    :param dirs: str -- 'x','y','z' or 'xy', 'yz' or 'xyz' or 'all'
+    :returns: (3,) list of mesh hints
+    """
+    hint = [None, None, None]
+    coord = point.GetCoord()
+    for ny in GetMultiDirs(dirs):
+        hint[ny] = [coord[ny],]
+    return hint
+
+def mesh_hint_from_box(box, dirs, **kw):
+    """ mesh_hint_from_box(box, dirs, metal_edge_res=None, **kw)
+
+    Get a grid hint for the edges of the given box with an an optional 2D metal
+    edge resolution.
+
+    :param dirs: str -- 'x','y','z' or 'xy', 'yz' or 'xyz' or 'all'
+    :param metal_edge_res: float -- 2D flat edge resolution
+    :returns: (3,) list of mesh hints
+    """
+    metal_edge_res = kw.get('metal_edge_res', None)
+    up_dir   = kw.get('up_dir'  , True)
+    down_dir = kw.get('down_dir', True)
+
+    if metal_edge_res is None:
+        mer = 0
+    else:
+        mer = np.array([-1.0, 2.0])/3 * metal_edge_res
+    if box.HasTransform():
+        sys.stderr.write('FDTD::automesh: Warning, cannot add edges to grid with transformations enabled\n')
+        return
+    hint = [None, None, None]
+    start = np.fmin(box.GetStart(), box.GetStop())
+    stop  = np.fmax(box.GetStart(), box.GetStop())
+    for ny in GetMultiDirs(dirs):
+        hint[ny] = []
+        if metal_edge_res is not None and stop[ny]-start[ny]>metal_edge_res:
+            if down_dir:
+                hint[ny].append(start[ny]-mer[0])
+                hint[ny].append(start[ny]-mer[1])
+            if up_dir:
+                hint[ny].append(stop[ny]+mer[0])
+                hint[ny].append(stop[ny]+mer[1])
+        elif stop[ny]-start[ny]:
+            if down_dir:
+                hint[ny].append(start[ny])
+            if up_dir:
+                hint[ny].append(stop[ny])
+        else:
+            hint[ny].append(start[ny])
+    return hint
+

python/openEMS/openEMS.pyx

@@ -19,7 +19,9 @@
 import os, sys, shutil
 import numpy as np
 cimport openEMS
-from . import ports, nf2ff
+from . import ports, nf2ff, automesh
+
+from CSXCAD.Utilities import GetMultiDirs
 
 cdef class openEMS:
     """ openEMS
@@ -267,7 +269,15 @@ cdef class openEMS:
         openEMS.ports.LumpedPort
         """
         assert self.__CSX is not None, 'AddLumpedPort: CSX is not set!'
-        return ports.LumpedPort(self.__CSX, port_nr, R, start, stop, p_dir, excite, **kw)
+        port = ports.LumpedPort(self.__CSX, port_nr, R, start, stop, p_dir, excite, **kw)
+        edges2grid = kw.get('edges2grid', None)
+        if edges2grid is not None:
+            grid = self.__CSX.GetGrid()
+            for n in GetMultiDirs(edges2grid):
+                grid.AddLine(n, start[n])
+                if start[n] != stop[n]:
+                    grid.AddLine(n, stop[n])
+        return port
 
     def AddWaveGuidePort(self, port_nr, start, stop, p_dir, E_func, H_func, kc, excite=0, **kw):
         """ AddWaveGuidePort(self, port_nr, start, stop, p_dir, E_func, H_func, kc, excite=0, **kw)
@@ -364,6 +374,42 @@ cdef class openEMS:
         self.__CSX = CSX
         self.thisptr.SetCSX(CSX.thisptr)
 
+    def GetCSX(self):
+        return self.__CSX
+
+    def AddEdges2Grid(self, dirs, primitives=None, properties=None, **kw):
+        """ AddEdges2Grid(primitives, dirs, **kw)
+
+        Add the edges of the given primitives to the FDTD grid.
+
+        :param dirs: primitives -- one or more primitives
+        :param dirs: str -- 'x','y','z' or 'xy', 'yz' or 'xyz' or 'all'
+        """
+        csx = self.GetCSX()
+        if csx is None:
+            raise Exception('AddEdges2Grid: Unable to access CSX!')
+        prim_list = []
+        if primitives is not None and  type(primitives) is not list:
+            prim_list.append(primitives)
+        elif primitives is not None:
+            prim_list += primitives
+
+        if properties is not None and  type(properties) is not list:
+            prim_list += properties.GetAllPrimitives()
+        elif primitives is not None:
+            for prop in properties:
+                prim_list += prop.GetAllPrimitives()
+
+        grid = csx.GetGrid()
+        for prim in prim_list:
+            hint = automesh.mesh_hint_from_primitive(prim, dirs, **kw)
+            if hint is None:
+                continue
+            for n in range(3):
+                if hint[n] is None:
+                    continue
+                grid.AddLine(n, hint[n])
+
     def Run(self, sim_path, cleanup=False, setup_only=False, verbose=None):
         """ Run(sim_path, cleanup=False, setup_only=False, verbose=None)
 

python/openEMS/ports.py

@@ -158,7 +158,7 @@ class LumpedPort(Port):
         elif self.R==0:
             lumped_R = CSX.AddMetal(self.lbl_temp.format('resist'))
 
-        lumped_R.AddBox(self.start, self.stop, priority=self.priority, edges2grid=kw.get('edges2grid', None))
+        lumped_R.AddBox(self.start, self.stop, priority=self.priority)
 
         if excite!=0:
             exc_vec = np.zeros(3)