CODEWITHSUNDEEP
pythonnumpy3dblendermeshlab
Xiiryo
Xiiryo

Reputation: 3267

Exporting 3D points to Blender via the .ply format creates an empty object, while it works in MeshLab

I made a Python script to create a .ply file using the image and the cloud of points of a scan 3D, stored as a NumPy array.

I can open the resulting file.ply in MeshLab. It works well.

But when I import it in Blender, there is no point. The resulting object is empty.

Do you have an idea on how to solve that?

Thanks

    def row_col_xyz_to_ply(self, xyz, rgb, name="output"):
            """Convers a numpy (row, col, xyz) cloud of points to ply format
    
                Parameters:
                xyz (NDArray): 3D points for each image pixel (row, col, (x,y,z))
                rbg (NDArray): RGBA values for each image pixel (row, col, (r,g,b,a))
    
                Returns:
                None: save the .ply file on the disk instead
            """
            
            # reshape
            # Extract the coordinates of the points where there is actual values (not NaN) in the xyz cloud of points
            points_rows, points_cols = np.where(~np.isnan(xyz[:,:,0]))
    
            # Grab the corresponding points in the xyz cloud of points in an array
            points_xyz = xyz[points_rows,points_cols,:] # n*3 array of 3D points (after nan filtering)
    
            # Grab the corresponding points in the image in an array
            points_image =  rgb[points_rows,points_cols,0:3] # n*3 array of RGB points (after nan filtering)
    
            # Create a dict of data
            data = {
                'x':     points_xyz[:,0],
                'y':     points_xyz[:,1],
                'z':     points_xyz[:,2], 
                'red':   points_image[:,0],
                'green': points_image[:,1],
                'blue':  points_image[:,2]
            }
            
            # Convert it to a cloud of points
            cloud = PyntCloud(pd.DataFrame(data=data))
    
            # Path where to save it
            filename = f"{name}.ply"
            path = os.path.join(self.path_exports,filename)
            
            # Save it
            cloud.to_file(path)
    
            # Debug
            print("row_col_xyz_to_ply > saved: ",filename)

Upvotes: 2

Views: 1425

Answers (2)

katelizkeat
katelizkeat

Reputation: 11

I ran into the same problem that Rockcat pointed out. I'm not sure if you're still looking for an answer but I found that this custom importer is a bit of a workaround. It imports every point as a vertex but doesn't need them to be connected

Upvotes: 1

Rockcat
Rockcat

Reputation: 3250

The problem is in the blender .ply importer. It doesn't support points that are not used by any triangle.

Upvotes: 1

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