Spaces:
Running
on
Zero
Running
on
Zero
# modified from https://github.com/Profactor/continuous-remeshing | |
import torch | |
import numpy as np | |
import trimesh | |
from typing import Tuple | |
def to_numpy(*args): | |
def convert(a): | |
if isinstance(a,torch.Tensor): | |
return a.detach().cpu().numpy() | |
assert a is None or isinstance(a,np.ndarray) | |
return a | |
return convert(args[0]) if len(args)==1 else tuple(convert(a) for a in args) | |
def laplacian( | |
num_verts:int, | |
edges: torch.Tensor #E,2 | |
) -> torch.Tensor: #sparse V,V | |
"""create sparse Laplacian matrix""" | |
V = num_verts | |
E = edges.shape[0] | |
#adjacency matrix, | |
idx = torch.cat([edges, edges.fliplr()], dim=0).type(torch.long).T # (2, 2*E) | |
ones = torch.ones(2*E, dtype=torch.float32, device=edges.device) | |
A = torch.sparse.FloatTensor(idx, ones, (V, V)) | |
#degree matrix | |
deg = torch.sparse.sum(A, dim=1).to_dense() | |
idx = torch.arange(V, device=edges.device) | |
idx = torch.stack([idx, idx], dim=0) | |
D = torch.sparse.FloatTensor(idx, deg, (V, V)) | |
return D - A | |
def _translation(x, y, z, device): | |
return torch.tensor([[1., 0, 0, x], | |
[0, 1, 0, y], | |
[0, 0, 1, z], | |
[0, 0, 0, 1]],device=device) #4,4 | |
def _projection(r, device, l=None, t=None, b=None, n=1.0, f=50.0, flip_y=True): | |
""" | |
see https://blog.csdn.net/wodownload2/article/details/85069240/ | |
""" | |
if l is None: | |
l = -r | |
if t is None: | |
t = r | |
if b is None: | |
b = -t | |
p = torch.zeros([4,4],device=device) | |
p[0,0] = 2*n/(r-l) | |
p[0,2] = (r+l)/(r-l) | |
p[1,1] = 2*n/(t-b) * (-1 if flip_y else 1) | |
p[1,2] = (t+b)/(t-b) | |
p[2,2] = -(f+n)/(f-n) | |
p[2,3] = -(2*f*n)/(f-n) | |
p[3,2] = -1 | |
return p #4,4 | |
def _orthographic(r, device, l=None, t=None, b=None, n=1.0, f=50.0, flip_y=True): | |
if l is None: | |
l = -r | |
if t is None: | |
t = r | |
if b is None: | |
b = -t | |
o = torch.zeros([4,4],device=device) | |
o[0,0] = 2/(r-l) | |
o[0,3] = -(r+l)/(r-l) | |
o[1,1] = 2/(t-b) * (-1 if flip_y else 1) | |
o[1,3] = -(t+b)/(t-b) | |
o[2,2] = -2/(f-n) | |
o[2,3] = -(f+n)/(f-n) | |
o[3,3] = 1 | |
return o #4,4 | |
def make_star_cameras(az_count,pol_count,distance:float=10.,r=None,image_size=[512,512],device='cuda'): | |
if r is None: | |
r = 1/distance | |
A = az_count | |
P = pol_count | |
C = A * P | |
phi = torch.arange(0,A) * (2*torch.pi/A) | |
phi_rot = torch.eye(3,device=device)[None,None].expand(A,1,3,3).clone() | |
phi_rot[:,0,2,2] = phi.cos() | |
phi_rot[:,0,2,0] = -phi.sin() | |
phi_rot[:,0,0,2] = phi.sin() | |
phi_rot[:,0,0,0] = phi.cos() | |
theta = torch.arange(1,P+1) * (torch.pi/(P+1)) - torch.pi/2 | |
theta_rot = torch.eye(3,device=device)[None,None].expand(1,P,3,3).clone() | |
theta_rot[0,:,1,1] = theta.cos() | |
theta_rot[0,:,1,2] = -theta.sin() | |
theta_rot[0,:,2,1] = theta.sin() | |
theta_rot[0,:,2,2] = theta.cos() | |
mv = torch.empty((C,4,4), device=device) | |
mv[:] = torch.eye(4, device=device) | |
mv[:,:3,:3] = (theta_rot @ phi_rot).reshape(C,3,3) | |
mv = _translation(0, 0, -distance, device) @ mv | |
return mv, _projection(r,device) | |
def make_star_cameras_orthographic(az_count,pol_count,distance:float=10.,r=None,image_size=[512,512],device='cuda'): | |
mv, _ = make_star_cameras(az_count,pol_count,distance,r,image_size,device) | |
if r is None: | |
r = 1 | |
return mv, _orthographic(r,device) | |
def make_sphere(level:int=2,radius=1.,device='cuda') -> Tuple[torch.Tensor,torch.Tensor]: | |
sphere = trimesh.creation.icosphere(subdivisions=level, radius=1.0, color=None) | |
vertices = torch.tensor(sphere.vertices, device=device, dtype=torch.float32) * radius | |
faces = torch.tensor(sphere.faces, device=device, dtype=torch.long) | |
return vertices,faces | |
from pytorch3d.renderer import ( | |
FoVOrthographicCameras, | |
look_at_view_transform, | |
) | |
def get_camera(R, T, focal_length=1 / (2**0.5)): | |
focal_length = 1 / focal_length | |
camera = FoVOrthographicCameras(device=R.device, R=R, T=T, min_x=-focal_length, max_x=focal_length, min_y=-focal_length, max_y=focal_length) | |
return camera | |
def make_star_cameras_orthographic_py3d(azim_list, device, focal=2/1.35, dist=1.1): | |
R, T = look_at_view_transform(dist, 0, azim_list) | |
focal_length = 1 / focal | |
return FoVOrthographicCameras(device=R.device, R=R, T=T, min_x=-focal_length, max_x=focal_length, min_y=-focal_length, max_y=focal_length).to(device) | |