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pythonopenglpyopengl

PyOpenGL OBJ Loader not loading correctly

I had a go at making an OBJ loader while following a tutorial and we ended up having roughly the same results. Mine wasn't loading properly so I copied his, and his didn't load properly. I sadly had to go and I had overlapped my code so I can't show it but here is his.

import numpy as np

class ObjLoader:
    def __init__(self):
        self.vert_coords = []
        self.text_coords = []
        self.norm_coords = []

        self.vertex_index = []
        self.texture_index = []
        self.normal_index = []

        self.model = []

    def load_model(self, file):
        for line in open(file, 'r'):
            if line.startswith('#'): continue
            values = line.split()
            if not values: continue

            if values[0] == 'v':
                self.vert_coords.append(values[1:4])
            if values[0] == 'vt':
                self.text_coords.append(values[1:3])
            if values[0] == 'vn':
                self.norm_coords.append(values[1:4])

            if values[0] == 'f':
                face_i = []
                text_i = []
                norm_i = []
                for v in values[1:4]:
                    w = v.split('/')
                    face_i.append(int(w[0])-1)
                    text_i.append(int(w[1])-1)
                    norm_i.append(int(w[2])-1)
                self.vertex_index.append(face_i)
                self.texture_index.append(text_i)
                self.normal_index.append(norm_i)

        self.vertex_index = [y for x in self.vertex_index for y in x]
        self.texture_index = [y for x in self.texture_index for y in x]
        self.normal_index = [y for x in self.normal_index for y in x]

        for i in self.vertex_index:
            self.model.extend(self.vert_coords[i])

        for i in self.texture_index:
            self.model.extend(self.text_coords[i])

        for i in self.normal_index:
            self.model.extend(self.norm_coords[i])

        self.model = np.array(self.model, dtype='float32')

Then on my main.py I executed the file with the file name.

obj = ObjLoader()

obj.load_model('cube2.obj')

shader = ShaderLoader.compile_shader("Shaders/vert.vs", "Shaders/frag.fs")

OBJ FILE: http://hatebin.com/adycgbuhgt

# Blender v2.79 (sub 0) OBJ File: ''
# www.blender.org
mtllib cube2.mtl
o Cube
v 1.000000 -1.000000 -1.000000
v 1.000000 -1.000000 1.000000
v -1.000000 -1.000000 1.000000
v -1.000000 -1.000000 -1.000000
v 1.000000 1.000000 -0.999999
v 0.999999 1.000000 1.000001
v -1.000000 1.000000 1.000000
v -1.000000 1.000000 -1.000000
vt 0.000000 0.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 0.000000 1.000000
vt 0.000000 0.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 0.000000 1.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 0.000000 1.000000
vt 0.000000 0.000000
vt 1.000000 0.000000
vt 0.000000 1.000000
vt 0.000000 0.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 0.000000 1.000000
vn 0.0000 -1.0000 0.0000
vn 0.0000 1.0000 0.0000
vn 1.0000 0.0000 0.0000
vn -0.0000 -0.0000 1.0000
vn -1.0000 -0.0000 -0.0000
vn 0.0000 0.0000 -1.0000
usemtl Material
s off
f 1/1/1 2/2/1 3/3/1 4/4/1
f 5/5/2 8/6/2 7/7/2 6/8/2
f 1/1/3 5/9/3 6/10/3 2/11/3
f 2/12/4 6/13/4 7/7/4 3/14/4
f 3/15/5 7/16/5 8/17/5 4/4/5
f 5/5/6 1/18/6 4/19/6 8/20/6

RESULT:

Solution

  • In order to display an obj file my script draws 3 verts in a form of a triangle. I had to triangulate my model in blender in order to draw triangles in my program and UV unwrap it to get my VT coords.