PLY: code cleanup

Group related and separate unrelated code, rename classes according to PEP8, remove redundant, outdated or misleading comments, greatly simplify UVs and vertex color variable init code.

io_mesh_ply/__init__.py

@@ -24,7 +24,7 @@ bl_info = {
     "version": (1, 1, 0),
     "blender": (2, 82, 0),
     "location": "File > Import-Export",
-    "description": "Import-Export PLY mesh data with UV's and vertex colors",
+    "description": "Import-Export PLY mesh data with UVs and vertex colors",
     "wiki_url": "https://docs.blender.org/manual/en/latest/addons/io_mesh_ply.html",
     "support": 'OFFICIAL',
     "category": "Import-Export",

io_mesh_ply/export_ply.py

@@ -34,44 +34,26 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
     def rvec2d(v):
         return round(v[0], 6), round(v[1], 6)
 
-    has_uv = bool(mesh.uv_layers)
-    has_vcol = bool(mesh.vertex_colors)
-
-    if not has_uv:
+    if use_uv_coords and mesh.uv_layers:
+        active_uv_layer = mesh.uv_layers.active.data
+    else:
         use_uv_coords = False
-    if not has_vcol:
-        use_colors = False
 
-    if not use_uv_coords:
-        has_uv = False
-    if not use_colors:
-        has_vcol = False
-
-    if has_uv:
-        active_uv_layer = mesh.uv_layers.active
-        if not active_uv_layer:
-            use_uv_coords = False
-            has_uv = False
-        else:
-            active_uv_layer = active_uv_layer.data
-
-    if has_vcol:
-        active_col_layer = mesh.vertex_colors.active
-        if not active_col_layer:
-            use_colors = False
-            has_vcol = False
-        else:
-            active_col_layer = active_col_layer.data
+    if use_colors and mesh.vertex_colors:
+        active_col_layer = mesh.vertex_colors.active.data
+    else:
+        use_colors = False
 
     # in case
     color = uvcoord = uvcoord_key = normal = normal_key = None
 
-    mesh_verts = mesh.vertices  # save a lookup
-    ply_verts = []  # list of dictionaries
+    mesh_verts = mesh.vertices
     # vdict = {} # (index, normal, uv) -> new index
     vdict = [{} for i in range(len(mesh_verts))]
+    ply_verts = []
     ply_faces = [[] for f in range(len(mesh.polygons))]
     vert_count = 0
+
     for i, f in enumerate(mesh.polygons):
 
         smooth = not use_normals or f.use_smooth
@@ -79,12 +61,12 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
             normal = f.normal[:]
             normal_key = rvec3d(normal)
 
-        if has_uv:
+        if use_uv_coords:
             uv = [
                 active_uv_layer[l].uv[:]
                 for l in range(f.loop_start, f.loop_start + f.loop_total)
             ]
-        if has_vcol:
+        if use_colors:
             col = [
                 active_col_layer[l].color[:]
                 for l in range(f.loop_start, f.loop_start + f.loop_total)
@@ -98,11 +80,11 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
                 normal = v.normal[:]
                 normal_key = rvec3d(normal)
 
-            if has_uv:
+            if use_uv_coords:
                 uvcoord = uv[j][0], uv[j][1]
                 uvcoord_key = rvec2d(uvcoord)
 
-            if has_vcol:
+            if use_colors:
                 color = col[j]
                 color = (
                     int(color[0] * 255.0),
@@ -115,7 +97,7 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
             vdict_local = vdict[vidx]
             pf_vidx = vdict_local.get(key)  # Will be None initially
 
-            if pf_vidx is None:  # same as vdict_local.has_key(key)
+            if pf_vidx is None:  # Same as vdict_local.has_key(key)
                 pf_vidx = vdict_local[key] = vert_count
                 ply_verts.append((vidx, normal, uvcoord, color))
                 vert_count += 1
@@ -136,13 +118,11 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
         )
 
         fw(f"element vertex {len(ply_verts)}\n")
-
         fw(
             "property float x\n"
             "property float y\n"
             "property float z\n"
         )
-
         if use_normals:
             fw(
                 "property float nx\n"
@@ -164,6 +144,7 @@ def save_mesh(filepath, mesh, use_normals=True, use_uv_coords=True, use_colors=T
 
         fw(f"element face {len(mesh.polygons)}\n")
         fw("property list uchar uint vertex_indices\n")
+
         fw("end_header\n")
 
         # Vertex data

io_mesh_ply/import_ply.py

@@ -19,7 +19,7 @@
 # <pep8 compliant>
 
 
-class element_spec(object):
+class ElementSpec:
     __slots__ = (
         "name",
         "count",
@@ -43,7 +43,7 @@ class element_spec(object):
         return -1
 
 
-class property_spec(object):
+class PropertySpec:
     __slots__ = (
         "name",
         "list_type",
@@ -102,7 +102,7 @@ class property_spec(object):
             return self.read_format(format, 1, self.numeric_type, stream)[0]
 
 
-class object_spec(object):
+class ObjectSpec:
     __slots__ = ("specs",)
 
     def __init__(self):
@@ -113,15 +113,16 @@ class object_spec(object):
         return dict([(i.name, [i.load(format, stream) for j in range(i.count)]) for i in self.specs])
 
         # Longhand for above LC
-
-        # answer = {}
-        # for i in self.specs:
-        #     answer[i.name] = []
-        #     for j in range(i.count):
-        #         if not j % 100 and meshtools.show_progress:
-        #             Blender.Window.DrawProgressBar(float(j) / i.count, 'Loading ' + i.name)
-        #         answer[i.name].append(i.load(format, stream))
-        # return answer
+        """
+        answer = {}
+        for i in self.specs:
+            answer[i.name] = []
+            for j in range(i.count):
+                if not j % 100 and meshtools.show_progress:
+                    Blender.Window.DrawProgressBar(float(j) / i.count, 'Loading ' + i.name)
+                answer[i.name].append(i.load(format, stream))
+        return answer
+        """
 
 
 def read(filepath):
@@ -154,7 +155,7 @@ def read(filepath):
         b'double': 'd',
         b'string': 's',
     }
-    obj_spec = object_spec()
+    obj_spec = ObjectSpec()
     invalid_ply = (None, None, None)
 
     with open(filepath, 'rb') as plyf:
@@ -206,15 +207,15 @@ def read(filepath):
                 if len(tokens) < 3:
                     print("Invalid element line")
                     return invalid_ply
-                obj_spec.specs.append(element_spec(tokens[1], int(tokens[2])))
+                obj_spec.specs.append(ElementSpec(tokens[1], int(tokens[2])))
             elif tokens[0] == b'property':
                 if not len(obj_spec.specs):
                     print("Property without element")
                     return invalid_ply
                 if tokens[1] == b'list':
-                    obj_spec.specs[-1].properties.append(property_spec(tokens[4], type_specs[tokens[2]], type_specs[tokens[3]]))
+                    obj_spec.specs[-1].properties.append(PropertySpec(tokens[4], type_specs[tokens[2]], type_specs[tokens[3]]))
                 else:
-                    obj_spec.specs[-1].properties.append(property_spec(tokens[2], None, type_specs[tokens[1]]))
+                    obj_spec.specs[-1].properties.append(PropertySpec(tokens[2], None, type_specs[tokens[1]]))
         if not valid_header:
             print("Invalid header ('end_header' line not found!)")
             return invalid_ply
@@ -373,7 +374,7 @@ def load_ply_mesh(filepath, ply_name):
 
     if texture and uvindices:
         pass
-        # XXX28: add support for using texture.
+        # TODO add support for using texture.
 
         # import os
         # import sys