fix 2d ply output for polymesh (#35)

CHANGELOG.rst

@@ -6,6 +6,12 @@ All notable changes to this project will be documented in this file.
 The format is based on `Keep a Changelog`_,
 and this project adheres to `Semantic Versioning`_.
 
+`1.4.3`_ - 2020-11-11
+--------------------------
+Fixed
+'''''''
+- PLY file format in 2D.
+
 `1.4.2`_ - 2020-11-3
 --------------------------
 Fixed
@@ -178,7 +184,8 @@ Added
 
 .. LINKS
 
-.. _`Unreleased`: https://github.com/kip-hart/MicroStructPy/compare/v1.4.2...HEAD
+.. _`Unreleased`: https://github.com/kip-hart/MicroStructPy/compare/v1.4.3...HEAD
+.. _`1.4.3`: https://github.com/kip-hart/MicroStructPy/compare/v1.4.2...v1.4.3
 .. _`1.4.2`: https://github.com/kip-hart/MicroStructPy/compare/v1.4.1...v1.4.2
 .. _`1.4.1`: https://github.com/kip-hart/MicroStructPy/compare/v1.4.0...v1.4.1
 .. _`1.4.0`: https://github.com/kip-hart/MicroStructPy/compare/v1.3.5...v1.4.0

src/microstructpy/__init__.py

@@ -4,4 +4,4 @@
 import microstructpy.seeding
 import microstructpy.verification
 
-__version__ = '1.4.2'
+__version__ = '1.4.3'

src/microstructpy/meshing/polymesh.py

@@ -273,25 +273,42 @@ def write(self, filename, format='txt'):
             nv = len(self.points)
             nd = len(self.points[0])
             nf = len(self.facets)
+            nr = len(self.regions)
             assert nd <= 3
-            axes = ['x', 'y', 'z'][:nd]
+
+            # Force 3D points 
+            pts = np.zeros((nv, 3))
+            pts[:, :nd] = self.points
+            axes = ['x', 'y', 'z']
 
             # header
             ply = 'ply\n'
             ply += 'format ascii 1.0\n'
             ply += 'element vertex ' + str(nv) + '\n'
             ply += ''.join(['property float32 ' + a + '\n' for a in axes])
-            ply += 'element face ' + str(nf) + '\n'
-            ply += 'property list uint8 int32 vertex_indices\n'
+            if nd == 2:
+                n_faces = nr
+            else:
+                n_faces = nf
+            ply += 'element face {}\n'.format(n_faces)
+            ply += 'property list uchar int vertex_indices\n'
             ply += 'end_header\n'
 
             # vertices
             ply += ''.join([' '.join(['{: e}'.format(x) for x in pt]) + '\n'
-                            for pt in self.points])
+                            for pt in pts])
 
             # faces
-            ply += ''.join([str(len(f)) + ''.join([' ' + str(kp) for kp in f])
-                            + '\n' for f in self.facets])
+            if nd == 2:  # regions -> faces
+                facets = np.array(self.facets)
+                ply += ''.join([str(len(r)) + ''.join([' ' + str(kp) for kp in
+                                                       kp_loop(facets[r])])
+                                + '\n' for r in self.regions])
+
+            else:  # facets -> faces
+                ply += ''.join([str(len(f)) + ''.join([' ' + str(kp)
+                                                       for kp in f])
+                                + '\n' for f in self.facets])
 
             with open(filename, 'w') as f:
                 f.write(ply)