Unexpected ComplexGen Reconstruction Results – Am I Missing Something?

[atntjt]

Thank you for this great project. I’m currently trying it out and have some questions because the results I’m getting don’t look correct to me. I’m wondering if I made a mistake somewhere along the way. Here’s my process:

Files: workspace.zip

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1. Point Cloud Data

I placed the point cloud file base_aufbereitet_Res256 - Kopie.ply in the folder /workspace/scripts/ (included in the ZIP archive).

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2. Increasing the Point Count to 10,000

To increase the number of points to 10,000, I used the script denisty_ply_utf8.py in /workspace/scripts/ with the following content (also in the ZIP archive):

import open3d as o3d
import numpy as np

# Load the point cloud
pcd = o3d.io.read_point_cloud("base_aufbereitet_Res256 - Kopie.ply")

# Optional: Calculate normals if not present
if not pcd.has_normals():
    pcd.estimate_normals(search_param=o3d.geometry.KDTreeSearchParamHybrid(radius=0.01, max_nn=30))

# Surface reconstruction (Poisson)
mesh, densities = o3d.geometry.TriangleMesh.create_from_point_cloud_poisson(pcd, depth=8)

# Sample a dense point cloud from the mesh
pcd_dense = mesh.sample_points_poisson_disk(number_of_points=10000)

# Save the point cloud
o3d.io.write_point_cloud("dichte_punktwolke_open3d.ply", pcd_dense)

After running:

/workspace/scripts# python denisty_ply_utf8.py

I got the file dichte_punktwolke_open3d.ply (included in the ZIP). Checking in Meshlab shows 10,000 points.

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3. Normalizing to [-0.5, 0.5]^3

Next, I ran meineNormalisierung_utf8.py (included in the ZIP) to normalize the points to [-0.5, 0.5]^3, with the following content:

import open3d as o3d
import numpy as np
import pickle
import numpy as np

# Paths according to ComplexGen structure
PATH_TEMPLATE_PKL = "/workspace/data/train_small/packed/packed_000000.pkl"
PATH_OUTPUT_PKL = "/workspace/data/default/test/packed/meinInput.pkl"

PATH_OUTPUT_PLY = "/workspace/data/default/test_point_clouds/00000006_0_10000.ply"

pcd = o3d.io.read_point_cloud("dichte_punktwolke_open3d.ply")

points_np = np.asarray(pcd.points)   # Nx3
normals_np = np.asarray(pcd.normals) # Nx3

# 2) Normalize to [-0.5, 0.5]^3
min_xyz = points_np.min(axis=0)
max_xyz = points_np.max(axis=0)
center = 0.5 * (min_xyz + max_xyz)
extent = (max_xyz - min_xyz).max()

pts_centered = points_np - center
pts_normed   = pts_centered / extent

# 3) Nx6: (x,y,z,nx,ny,nz)
surface_points = np.hstack([pts_normed, normals_np])  # shape (N,6)

#################################
# Part A: Creating .pkl
#################################

# Load template
with open(PATH_TEMPLATE_PKL, "rb") as fin:
    sample = pickle.load(fin)

# surface_points Nx6
sample['surface_points'] = surface_points

# Write new file meinInput.pkl
with open(PATH_OUTPUT_PKL, "wb") as fout:
    pickle.dump(sample, fout)

print(f"Done: {PATH_OUTPUT_PKL} created and surface_points replaced.")

#################################
# Part B: ASCII-PLY
#################################

pcd_out = o3d.geometry.PointCloud()
pcd_out.points  = o3d.utility.Vector3dVector(pts_normed)
pcd_out.normals = o3d.utility.Vector3dVector(normals_np)

# ASCII format
o3d.io.write_point_cloud(
    PATH_OUTPUT_PLY,
    pcd_out,
    write_ascii=True
)

print(f"Done: ASCII-PLY {PATH_OUTPUT_PLY} written.")

After running:

/workspace/scripts# python meineNormalisierung_utf8.py

I got the following files (in the ZIP archive):

• /workspace/data/default/test/packed/meinInput.pkl
• /workspace/data/default/test_point_clouds/00000006_0_10000.ply

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4. Choosing and Running a Test Script

We can choose from test_default.sh, test_noise002.sh, test_noise005.sh, or test_partial.sh. I previously tried test_default.sh, test_noise002.sh, and test_partial.sh, but none of them seemed to produce a correct result. Therefore, I decided to use test_noise005.sh. In that file, I also changed --gpu 0 to --gpu 0,1,2,3,4.

Execute with:

/workspace# ./scripts/test_noise005.sh

This generated new files in the folder /workspace/experiments/noise005/test_obj/ (in the ZIP).

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5. Running extraction_noise005.sh

Then, I ran the script extraction_noise005.sh.

• Before running it, I modified gurobi_wrapper.py under /workspace/PostProcess/:
  • max_time = 5*60 to max_time = 120*60 (otherwise the gap remains high)
  • m.setParam('Threads', 2) to m.setParam('Threads', 24) (not sure if it helps)

Execute with:

/workspace# ./scripts/extraction_noise005.sh

After 2 hours, (which seems quite long?) Gap of 0.58%. The new files in /workspace/experiments/noise005/test_obj/ (in the ZIP) are:

• /workspace/experiments/noise005/test_obj/00000006_0_prediction.complex
• /workspace/experiments/noise005/test_obj/00000006_0_extraction.complex

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6. Visualizing .complex Files

Now I want to visualize 00000006_0_prediction.complex and 00000006_0_extraction.complex. According to the instructions, I first copy complexgen.mtl:

/workspace# cp /workspace/vis/complexgen.mtl /workspace/experiments/noise005/test_obj/complexgen.mtl

Then:

/workspace# cd vis
/workspace/vis# python gen_vis_result.py -i /workspace/experiments/noise005/test_obj/00000006_0_prediction.complex
/workspace/vis# python gen_vis_result.py -i /workspace/experiments/noise005/test_obj/00000006_0_extraction.complex
/workspace# cd ..

This produces:

• /workspace/experiments/noise005/test_obj/00000006_0_extraction.obj
• /workspace/experiments/noise005/test_obj/00000006_0_prediction.obj

00000006_0_extraction.obj

00000006_0_prediction.obj

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7. Running geometric_refine.py --noise

Next, I run geometric_refine.py --noise (because it’s recommended for noisy/partial data). Before that, I updated these paths in the script:

exe_path = r'./GeometricRefine/Bin/GeometricRefine'
pc_ply_path = r'./data/default/test_point_clouds'

# complex_path = r'./experiments/default/test_obj'
# complex_path = r'./experiments/partial/test_obj'
# complex_path = r'./experiments/noise002/test_obj'

complex_path = r'./experiments/noise005/test_obj'

Execute with:

/workspace# python ./scripts/geometric_refine.py --noise

The script generates more files (in the ZIP):

• /workspace/experiments/noise005/test_obj/00000006_0_geom_refine.json
• /workspace/experiments/noise005/test_obj/00000006_0_extraction_input.json

Then I visualize them with gen_vis_result.py:

/workspace# cd vis
/workspace/vis# python gen_vis_result.py -i /workspace/experiments/noise005/test_obj/00000006_0_geom_refine.json
/workspace/vis# python gen_vis_result.py -i /workspace/experiments/noise005/test_obj/00000006_0_extraction_input.json
/workspace# cd ..

This produces:

• /workspace/experiments/noise005/test_obj/00000006_0_geom_refine.obj
• /workspace/experiments/noise005/test_obj/00000006_0_extraction_input.obj

00000006_0_geom_refine.obj

00000006_0_extraction_input.obj

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8. Question / Observation

I’m wondering if I might have overlooked something in my process. The point cloud doesn’t seem particularly complex, so I was hoping ComplexGen could handle and visualize it easily. I successfully created the example 00861558_0_10000.ply (included in the ZIP under ComplexGen_Example).

I’d really appreciate any feedback, tips, or suggestions on how to solve this.
Thank you again for this great project!

[SmallMonster]

Is the problem fixed now?