model-converter-python/d3/model/formats/obj.py

189 lines
5.9 KiB
Python

from ..basemodel import TextModelParser, Exporter, Vertex, TexCoord, Normal, FaceVertex, Face
from ..mesh import Material, MeshPart
from functools import reduce
import os.path
import sys
def is_obj(filename):
"""Checks that the file is a .obj file
Only checks the extension of the file
:param filename: path to the file
"""
return filename[-4:] == '.obj'
class OBJParser(TextModelParser):
"""Parser that parses a .obj file
"""
def __init__(self, up_conversion = None):
super().__init__(up_conversion)
self.current_material = None
self.mtl = None
def parse_line(self, string):
"""Parses a line of .obj file
:param string: the line to parse
"""
if string == '':
return
split = string.split()
first = split[0]
split = split[1:]
if first == 'usemtl' and self.mtl is not None:
self.current_material = self.mtl[split[0]]
elif first == 'mtllib':
path = os.path.join(os.path.dirname(self.path), split[0])
if os.path.isfile(path):
self.mtl = MTLParser(self)
self.mtl.parse_file(path)
else:
print('Warning : ' + path + ' not found ', file=sys.stderr)
elif first == 'v':
self.add_vertex(Vertex().from_array(split))
elif first == 'vn':
self.add_normal(Normal().from_array(split))
elif first == 'vt':
self.add_tex_coord(TexCoord().from_array(split))
elif first == 'f':
splits = list(map(lambda x: x.split('/'), split))
for i in range(len(splits)):
for j in range(len(splits[i])):
if splits[i][j] is not '':
splits[i][j] = int(splits[i][j])
if splits[i][j] > 0:
splits[i][j] -= 1
else:
splits[i][j] = len(self.vertices) + splits[i][j]
# if Face3
if len(split) == 3:
face = Face().from_array(splits)
face.material = self.current_material
self.add_face(face)
elif len(split) == 4:
face = Face().from_array(splits[:3])
face.material = self.current_material
self.add_face(face)
face = Face().from_array([splits[0], splits[2], splits[3]])
face.material = self.current_material
self.add_face(face)
else:
print('Face with more than 4 vertices are not supported', file=sys.stderr)
class MTLParser:
"""Parser that parses a .mtl material file
"""
def __init__(self, parent):
"""Creates a MTLParser bound to the OBJParser
:param parent: the OBJParser this MTLParser refers to
"""
self.parent = parent
self.current_mtl = None
def parse_line(self, string):
"""Parses a line of .mtl file
:param string: line to parse
"""
if string == '':
return
split = string.split()
first = split[0]
split = split[1:]
if first == 'newmtl':
self.current_mtl = Material(split[0])
self.parent.materials.append(self.current_mtl)
elif first == 'Ka':
self.current_mtl.Ka = Vertex().from_array(split)
elif first == 'Kd':
self.current_mtl.Kd = Vertex().from_array(split)
elif first == 'Ks':
self.current_mtl.Ks = Vertex().from_array(split)
elif first == 'map_Kd':
self.current_mtl.relative_path_to_texture = split[0]
self.current_mtl.absolute_path_to_texture = os.path.join(os.path.dirname(self.parent.path), split[0])
def parse_file(self, path):
with open(path) as f:
for line in f.readlines():
line = line.rstrip()
self.parse_line(line)
def __getitem__(self, key):
for material in self.parent.materials:
if material.name == key:
return material
class OBJExporter(Exporter):
"""Exporter to .obj format
"""
def __init__(self, model):
"""Creates an exporter from the model
:param model: Model to export
"""
super().__init__(model)
def __str__(self):
"""Exports the model
"""
current_material = ''
string = ""
for vertex in self.model.vertices:
string += "v " + ' '.join([str(vertex.x), str(vertex.y), str(vertex.z)]) + "\n"
string += "\n"
if len(self.model.tex_coords) > 0:
for tex_coord in self.model.tex_coords:
string += "vt " + ' '.join([str(tex_coord.x), str(tex_coord.y)]) + "\n"
string += "\n"
if len(self.model.normals) > 0:
for normal in self.model.normals:
string += "vn " + ' '.join([str(normal.x), str(normal.y), str(normal.z)]) + "\n"
string += "\n"
faces = sum(map(lambda x: x.faces, self.model.parts), [])
for face in faces:
if face.material is not None and face.material.name != current_material:
current_material = face.material.name
string += "usemtl " + current_material + "\n"
string += "f "
arr = []
for v in [face.a, face.b, face.c]:
sub_arr = []
sub_arr.append(str(v.vertex + 1))
if v.normal is None:
if v.tex_coord is not None:
sub_arr.append('')
sub_arr.append(str(v.tex_coord + 1))
elif v.tex_coord is not None:
sub_arr.append(str(v.tex_coord + 1))
if v.normal is not None:
sub_arr.append(str(v.normal + 1))
arr.append('/'.join(sub_arr))
string += ' '.join(arr) + '\n'
return string