fix gltf export

cq-cli.py

@@ -390,8 +390,14 @@ def main():
             if outfile == None:
                 print(converted)
             else:
-                with open(outfile, 'w') as file:
-                    file.write(converted)
+                if isinstance(converted, str):
+                    with open(outfile, 'w') as file:
+                        file.write(converted)
+                elif isinstance(converted, (bytes, bytearray)):
+                    with open(outfile, 'wb') as file:
+                        file.write(converted)
+                else:
+                    raise TypeError("Expected converted output to be str, bytes, or bytearray. Got '%s'" % type(converted).__name__)
 
     except Exception:
         out_tb = traceback.format_exc()

cqcodecs/cq_codec_gltf.py

@@ -13,12 +13,12 @@ def convert(build_result, output_file=None, error_file=None, output_opts=None):
         # Put the GLTF output into the temp file
         # Check to see if we are dealing with an assembly or a single object
         if type(build_result.first_result.shape).__name__ == "Assembly":
-            build_result.first_result.shape.save(temp_file, binary=False)
+            build_result.first_result.shape.save(temp_file)
         else:
             raise ValueError("GLTF export is only available for CadQuery assemblies at this time")
 
     # Read the GLTF output back in
-    with open(temp_file, 'r') as file:
+    with open(temp_file, 'rb') as file:
         gltf_str = file.read()
 
-    return gltf_str
+    return gltf_str