t0 = time.time()

vertices= np.load(vpath)

faces = np.load(fpath)

print(f"Applying simplification with reduction {reduction}...")

points_out, faces_out, collapses = fast_simplification.simplify(vertices, faces, reduction,

return_collapses=True)

newvpath = os.path.join(os.path.dirname(vpath), f"vertices_simplified{reduction}.npy")

newfpath = os.path.join(os.path.dirname(fpath), f"faces_simplified{reduction}.npy")

np.save(newvpath, points_out)

np.save(newfpath, faces_out)

t2 = (time.time() - t0) / 60

print(f"Time taken: {t2} minutes")

t0 = time.time()

print(f"Loading mesh from {trimesh}...")

import igl

if trimesh.endswith(".obj"):

v, tc, n, f, ftc, _ = igl.readOBJ(trimesh)

if len(tc) == 0:

tc = None

ftc = None

else:

v, f = igl.read_triangle_mesh(trimesh)

tc = None

ftc = None

v = v.astype(np.float32)

f = f.astype(np.int32)

print(f"Applying simplification with reduction {reduction}...")

points_out, faces_out, collapses = fast_simplification.simplify(v, f, reduction,

return_collapses=True)

# Transfer texture coordinates if exist

if tc is not None:

points_out, faces_out, indice_mapping = fast_simplification.replay_simplification(v, f, collapses)

# Map tc to lr textures

reverse_indice_mapping = np.zeros(len(points_out), dtype=int)

reverse_indice_mapping[indice_mapping] = np.arange(len(indice_mapping))

# Map v to tc

vcorners = f.flatten()

tcorners = ftc.flatten()

vtotc = np.zeros(len(v), dtype=int)

vtotc[vcorners] = tcorners

new_uv = tc[vtotc[reverse_indice_mapping]]

new_fuv = faces_out

# Create mapping from hr corners to tc

hrcorner_to_tc = ftc.flatten() # Based on canonical mapping to corners

# Create mapping from hr corners to lr points

hrcorner_to_lrv = indice_mapping[f].flatten() # hr corners => lr points

# Reverse mapping from lr points to hr corners

lrv_to_hrcorner = np.zeros(len(points_out), dtype=int)

lrv_to_hrcorner[hrcorner_to_lrv] = np.arange(len(hrcorner_to_lrv))

# LR corners to LR points

lr_corners = faces_out.flatten()

new_uv = tc[hrcorner_to_tc[lrv_to_hrcorner[lr_corners]]] # F'*3 x 2

new_fuv = np.arange(len(new_uv)).reshape(-1, 3) # F'*3 x 3

if savename is None:

meshname = os.path.basename(trimesh).split(".")[0]

savename = f"{meshname}_simplified{reduction}.obj"

savedir = os.path.join(os.path.dirname(trimesh), savename)

from utils import export_obj

export_obj(savedir, points_out, faces_out, uv=new_uv if tc is not None else None,

fuv=new_fuv if tc is not None else None)

print(f"Mesh saved to {savedir}")

t2 = (time.time() - t0) / 60

print(f"Time taken: {t2} minutes")

t0 = time.time()

print(f"Loading mesh from {trimesh}...")

import igl

if trimesh.endswith(".obj"):

v, tc, n, f, ftc, _ = igl.readOBJ(trimesh)

if len(tc) == 0:

tc = None

ftc = None

else:

v, f = igl.read_triangle_mesh(trimesh)

tc = None

ftc = None

v = v.astype(np.float32)

f = f.astype(np.int32)

print(f"Applying simplification with reduction {reduction}...")

points_out, faces_out, collapses = fast_simplification.simplify(v, f, reduction,

return_collapses=True)

# Transfer texture coordinates if exist

if tc is not None:

points_out, faces_out, indice_mapping = fast_simplification.replay_simplification(v, f, collapses)

# Map tc to lr textures

reverse_indice_mapping = np.zeros(len(points_out), dtype=int)

reverse_indice_mapping[indice_mapping] = np.arange(len(indice_mapping))

# Map v to tc

vcorners = f.flatten()

tcorners = ftc.flatten()

vtotc = np.zeros(len(v), dtype=int)

vtotc[vcorners] = tcorners

new_uv = tc[vtotc[reverse_indice_mapping]]

new_fuv = faces_out

# Create mapping from hr corners to tc

hrcorner_to_tc = ftc.flatten() # Based on canonical mapping to corners

# Create mapping from hr corners to lr points

hrcorner_to_lrv = indice_mapping[f].flatten() # hr corners => lr points

# Reverse mapping from lr points to hr corners

lrv_to_hrcorner = np.zeros(len(points_out), dtype=int)

lrv_to_hrcorner[hrcorner_to_lrv] = np.arange(len(hrcorner_to_lrv))

# LR corners to LR points

lr_corners = faces_out.flatten()

new_uv = tc[hrcorner_to_tc[lrv_to_hrcorner[lr_corners]]] # F'*3 x 2

new_fuv = np.arange(len(new_uv)).reshape(-1, 3) # F'*3 x 3

if savename is None:

meshname = os.path.basename(trimesh).split(".")[0]

savename = f"{meshname}_simplified{reduction}.obj"

savedir = os.path.join(os.path.dirname(trimesh), savename)

from utils import export_obj

export_obj(savedir, points_out, faces_out, uv=new_uv if tc is not None else None,

fuv=new_fuv if tc is not None else None)

print(f"Mesh saved to {savedir}")

t2 = (time.time() - t0) / 60

print(f"Time taken: {t2} minutes")

t0 = time.time()

v = vertices.astype(np.float32)

f = faces.astype(np.int32)

tc = uvs.astype(np.float32) if uvs is not None else None

ftc = fuv.astype(np.int32) if fuv is not None else f

print(f"Applying simplification with reduction {reduction}...")

points_out, faces_out, collapses = fast_simplification.simplify(v, f, reduction,

return_collapses=True)

# Transfer texture coordinates if exist

if tc is not None:

points_out, faces_out, indice_mapping = fast_simplification.replay_simplification(v, f, collapses)

# Map tc to lr textures

reverse_indice_mapping = np.zeros(len(points_out), dtype=int)

reverse_indice_mapping[indice_mapping] = np.arange(len(indice_mapping))

# Map v to tc

vcorners = f.flatten()

tcorners = ftc.flatten()

vtotc = np.zeros(len(v), dtype=int)

vtotc[vcorners] = tcorners

new_uv = tc[vtotc[reverse_indice_mapping]]

new_fuv = faces_out

# Create mapping from hr corners to tc

hrcorner_to_tc = ftc.flatten() # Based on canonical mapping to corners

# Create mapping from hr corners to lr points

hrcorner_to_lrv = indice_mapping[f].flatten() # hr corners => lr points

# Reverse mapping from lr points to hr corners

lrv_to_hrcorner = np.zeros(len(points_out), dtype=int)

lrv_to_hrcorner[hrcorner_to_lrv] = np.arange(len(hrcorner_to_lrv))

# LR corners to LR points

lr_corners = faces_out.flatten()

new_uv = tc[hrcorner_to_tc[lrv_to_hrcorner[lr_corners]]] # F'*3 x 2

new_fuv = np.arange(len(new_uv)).reshape(-1, 3) # F'*3 x 3

from utils import export_obj

export_obj(savepath, points_out, faces_out, uv=new_uv if tc is not None else None,

fuv=new_fuv if tc is not None else None)

print(f"Mesh saved to {savepath}")

t2 = (time.time() - t0) / 60

print(f"Time taken: {t2} minutes")

import subprocess

t0 = time.time()

subprocess.run(["npx", "@gltf-transform/cli", "weld", gltfpath, savepath])

subprocess.run(["npx", "@gltf-transform/cli", "simplify", savepath, savepath, "--ratio", str(reduction), "--error", "1"])

print(f"Mesh saved to {savepath}")

t2 = (time.time() - t0) / 60

print(f"Time taken: {t2} minutes")