File size: 8,454 Bytes
2fe3da0 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 |
# Copyright (c) 2020-2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
#
# NVIDIA CORPORATION, its affiliates and licensors retain all intellectual
# property and proprietary rights in and to this material, related
# documentation and any modifications thereto. Any use, reproduction,
# disclosure or distribution of this material and related documentation
# without an express license agreement from NVIDIA CORPORATION or
# its affiliates is strictly prohibited.
import os
import torch
from . import texture
from . import mesh
from . import material
######################################################################################
# Utility functions
######################################################################################
def _find_mat(materials, name):
for mat in materials:
if mat['name'] == name:
return mat
return materials[0] # Materials 0 is the default
def normalize_mesh(vertices, scale_factor=1.0):
# 计算边界框
min_vals, _ = torch.min(vertices, dim=0)
max_vals, _ = torch.max(vertices, dim=0)
# 计算中心点
center = (max_vals + min_vals) / 2
# 平移顶点
vertices = vertices - center
# 计算缩放因子
max_extent = torch.max(max_vals - min_vals)
scale = 2.0 * scale_factor / max_extent
# 缩放顶点
vertices = vertices * scale
return vertices
######################################################################################
# Create mesh object from objfile
######################################################################################
def rotate_y_90(v_pos):
# 定义绕X轴旋转90度的旋转矩阵
rotate_y = torch.tensor([[0, 0, 1, 0],
[0, 1, 0, 0],
[-1, 0, 0, 0],
[0, 0, 0, 1]], dtype=torch.float32, device=v_pos.device)
return rotate_y
def load_obj(filename, clear_ks=True, mtl_override=None, return_attributes=False, path_is_attributrs=False, scale_factor=1.0):
obj_path = os.path.dirname(filename)
# Read entire file
with open(filename, 'r') as f:
lines = f.readlines()
# Load materials
all_materials = [
{
'name' : '_default_mat',
'bsdf' : 'pbr',
'kd' : texture.Texture2D(torch.tensor([0.5, 0.5, 0.5], dtype=torch.float32, device='cuda')),
'ks' : texture.Texture2D(torch.tensor([0.0, 0.0, 0.0], dtype=torch.float32, device='cuda'))
}
]
if mtl_override is None:
for line in lines:
if len(line.split()) == 0:
continue
if line.split()[0] == 'mtllib':
all_materials += material.load_mtl(os.path.join(obj_path, line.split()[1]), clear_ks) # Read in entire material library
else:
all_materials += material.load_mtl(mtl_override)
# load vertices
vertices, texcoords, normals = [], [], []
for line in lines:
if len(line.split()) == 0:
continue
prefix = line.split()[0].lower()
if prefix == 'v':
vertices.append([float(v) for v in line.split()[1:]])
elif prefix == 'vt':
val = [float(v) for v in line.split()[1:]]
texcoords.append([val[0], 1.0 - val[1]])
elif prefix == 'vn':
normals.append([float(v) for v in line.split()[1:]])
# load faces
activeMatIdx = None
used_materials = []
faces, tfaces, nfaces, mfaces = [], [], [], []
for line in lines:
if len(line.split()) == 0:
continue
prefix = line.split()[0].lower()
if prefix == 'usemtl': # Track used materials
mat = _find_mat(all_materials, line.split()[1])
if not mat in used_materials:
used_materials.append(mat)
activeMatIdx = used_materials.index(mat)
elif prefix == 'f': # Parse face
vs = line.split()[1:]
nv = len(vs)
vv = vs[0].split('/')
v0 = int(vv[0]) - 1
t0 = int(vv[1]) - 1 if vv[1] != "" else -1
n0 = int(vv[2]) - 1 if vv[2] != "" else -1
for i in range(nv - 2): # Triangulate polygons
vv = vs[i + 1].split('/')
v1 = int(vv[0]) - 1
t1 = int(vv[1]) - 1 if vv[1] != "" else -1
n1 = int(vv[2]) - 1 if vv[2] != "" else -1
vv = vs[i + 2].split('/')
v2 = int(vv[0]) - 1
t2 = int(vv[1]) - 1 if vv[1] != "" else -1
n2 = int(vv[2]) - 1 if vv[2] != "" else -1
mfaces.append(activeMatIdx)
faces.append([v0, v1, v2])
tfaces.append([t0, t1, t2])
nfaces.append([n0, n1, n2])
assert len(tfaces) == len(faces) and len(nfaces) == len (faces)
# Create an "uber" material by combining all textures into a larger texture
if len(used_materials) > 1:
uber_material, texcoords, tfaces = material.merge_materials(used_materials, texcoords, tfaces, mfaces)
else:
uber_material = used_materials[0]
vertices = torch.tensor(vertices, dtype=torch.float32, device='cuda')
texcoords = torch.tensor(texcoords, dtype=torch.float32, device='cuda') if len(texcoords) > 0 else None
normals = torch.tensor(normals, dtype=torch.float32, device='cuda') if len(normals) > 0 else None
faces = torch.tensor(faces, dtype=torch.int64, device='cuda')
tfaces = torch.tensor(tfaces, dtype=torch.int64, device='cuda') if texcoords is not None else None
nfaces = torch.tensor(nfaces, dtype=torch.int64, device='cuda') if normals is not None else None
vertices = normalize_mesh(vertices, scale_factor=scale_factor)
# vertices = vertices @ rotate_y_90(vertices)[:3,:3]
if return_attributes:
return mesh.Mesh(vertices, faces, normals, nfaces, texcoords, tfaces, material=uber_material), vertices, faces, normals, nfaces, texcoords, tfaces, uber_material
return mesh.Mesh(vertices, faces, normals, nfaces, texcoords, tfaces, material=uber_material)
######################################################################################
# Save mesh object to objfile
######################################################################################
def write_obj(folder, mesh, save_material=True):
obj_file = os.path.join(folder, 'mesh.obj')
print("Writing mesh: ", obj_file)
with open(obj_file, "w") as f:
f.write("mtllib mesh.mtl\n")
f.write("g default\n")
v_pos = mesh.v_pos.detach().cpu().numpy() if mesh.v_pos is not None else None
v_nrm = mesh.v_nrm.detach().cpu().numpy() if mesh.v_nrm is not None else None
v_tex = mesh.v_tex.detach().cpu().numpy() if mesh.v_tex is not None else None
t_pos_idx = mesh.t_pos_idx.detach().cpu().numpy() if mesh.t_pos_idx is not None else None
t_nrm_idx = mesh.t_nrm_idx.detach().cpu().numpy() if mesh.t_nrm_idx is not None else None
t_tex_idx = mesh.t_tex_idx.detach().cpu().numpy() if mesh.t_tex_idx is not None else None
print(" writing %d vertices" % len(v_pos))
for v in v_pos:
f.write('v {} {} {} \n'.format(v[0], v[1], v[2]))
if v_tex is not None:
print(" writing %d texcoords" % len(v_tex))
assert(len(t_pos_idx) == len(t_tex_idx))
for v in v_tex:
f.write('vt {} {} \n'.format(v[0], 1.0 - v[1]))
if v_nrm is not None:
print(" writing %d normals" % len(v_nrm))
assert(len(t_pos_idx) == len(t_nrm_idx))
for v in v_nrm:
f.write('vn {} {} {}\n'.format(v[0], v[1], v[2]))
# faces
f.write("s 1 \n")
f.write("g pMesh1\n")
f.write("usemtl defaultMat\n")
# Write faces
print(" writing %d faces" % len(t_pos_idx))
for i in range(len(t_pos_idx)):
f.write("f ")
for j in range(3):
f.write(' %s/%s/%s' % (str(t_pos_idx[i][j]+1), '' if v_tex is None else str(t_tex_idx[i][j]+1), '' if v_nrm is None else str(t_nrm_idx[i][j]+1)))
f.write("\n")
if save_material:
mtl_file = os.path.join(folder, 'mesh.mtl')
print("Writing material: ", mtl_file)
material.save_mtl(mtl_file, mesh.material)
print("Done exporting mesh")
|