bug(import_bsi): Fix incorrect BSIZ parsing

addons/bitsquid/import_bsi.py

@@ -15,13 +15,16 @@
 #    along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 
+import sys
 import zlib
 import json
 import bpy
 import math
+import traceback
 
 from mathutils import Vector, Matrix
 from bpy_extras.io_utils import unpack_list
+from bitsquid import sjson
 
 
 def parse_sjson(file_path, skip_editor_data=True):
@@ -32,12 +35,11 @@ def parse_sjson(file_path, skip_editor_data=True):
         Taken from `bsi_import` in the Vermintide 2 SDK, but slightly
         modified to fix some issues and improve readability.
     """
-    return_dict = {}
-    try:
+
     with open(file_path, 'rb') as f:
         data = f.read()
 
-            if data[:4] == 'bsiz':
+        if data[:4] == b'bsiz':
             data = zlib.decompress(data[8:])
 
         data = data.decode("utf-8")
@@ -162,10 +164,7 @@ def parse_sjson(file_path, skip_editor_data=True):
             file_lines[-1] = file_lines[-1][:-2] + '\n'
 
         file_lines.append('}\n')
-            return_dict = json.loads(''.join(file_lines))
-    except ValueError:
-        print(file_path.replace('\\', '/') + ': SJSON file contains a syntax error')
-    return return_dict
+        return json.loads(''.join(file_lines))
 
 
 def find(arr, f):
@@ -180,14 +179,15 @@ def find(arr, f):
 
 def create_mesh(self, context, name, node_data, geo_data):
     """
-    Create a Blender object from a BSI node definition
+    Create a Blender mesh object from a BSI node definition
     and additional data from the file.
     """
 
-    # A list of vectors that represent vertex locations.
+    # A list of 3-dimensional vectors. Each vector encodes a vertex position.
     vertices = []
-    # A list of vectors, where each vector contains three indices into `vertices`.
-    # Those three indices define the vertices that make up the face.
+    # A list of vectors, where each vector contains three indices into
+    # `vertices`. Those three indices define the vertices that make up
+    # the face.
     faces = []
     uv_name = "UVMap"
     uvs = []
@@ -204,11 +204,11 @@ def create_mesh(self, context, name, node_data, geo_data):
                 # stride would only be possible for objects that can be built
                 # entirely from quads, which is very uncommon.
                 if stride != 3:
-                    raise RuntimeError("stride != 3 cannot be handled")
+                    raise NotImplementedError("stride != 3 cannot be handled")
 
                 # Get vertex positions.
-                # Iterate over data in sets of three values that represent
-                # `x`, `y` and `z`.
+                # Iterate over data in sets of three values. Each set
+                # represents `x`, `y` and `z`.
                 for j in range(0, len(stream_data), 3):
                     vertices.append(Vector((
                         stream_data[j],
@@ -224,6 +224,9 @@ def create_mesh(self, context, name, node_data, geo_data):
                         index_stream[j + 1],
                         index_stream[j + 2],
                     )))
+
+                print(vertices)
+                print(faces)
             elif channel["name"] == 'NORMAL':
                 # Blender is able to create normals from the face definition
                 # (i.e. the order in which the faces vertices were defined)
@@ -464,10 +467,12 @@ def import_geometry(self, context, name, node_data, global_data):
     obj = bpy.data.objects.new(mesh.name, mesh)
     obj.matrix_world = Matrix()
 
+    # Check of a local offset
     if "local" in node_data:
         mat = matrix_from_list(node_data["local"])
         obj.matrix_local = mat
 
+    # Recurse into child nodes and parent them to the current object
     if "children" in node_data:
         for child_name, child_data in node_data["children"].items():
             if child_data["parent"] != name:
@@ -517,6 +522,9 @@ def import_node(self, context, name, node_data, global_data):
     if has_geometry:
         return import_geometry(self, context, name, node_data, global_data)
     else:
+        # Only the root node should be left now.
+        # It needs slightly different treatment compared to a regular geometry
+        # node
         if name != "root_point":
             self.report({'WARNING'}, "Unknown kind of node: '{}'. Falling back to Empty.".format(name))
 
@@ -550,7 +558,19 @@ def import_node(self, context, name, node_data, global_data):
 
 
 def load(self, context, filepath, *, relpath=None):
-    global_data = parse_sjson(filepath)
+    try:
+        with open(filepath, 'rb') as f:
+            data = f.read()
+
+            if data[:4] == b'bsiz':
+                data = zlib.decompress(data[8:])
+
+            data = data.decode("utf-8")
+            global_data = sjson.loads(data)
+    except Exception:
+        self.report({'ERROR'}, "Failed to parse SJSON: {}".format(filepath))
+        traceback.print_exc(file=sys.stderr)
+        return {'CANCELLED'}
 
     # Nothing to do if there are no nodes
     if "nodes" not in global_data: