Use the latest pycolmap

[npu-chenlin]

• Use pycolmap.Reconstruction instead of SceneManager

• Use CameraModelId instead of string comparison

[johnvanatta-plus]

I don't think I can review this--I'm not part of the gsplat team, so I don't know what they plan for on Colmap version compatibility. I've used this patch for my own project and it works well. Sorry :)

[MomokoMatsuo]

Hi @npu-chenlin .
Great PR I think but there is a bug in reading distortion parameters.
Please follow the issue: #794

[npu-chenlin]

Hi @npu-chenlin . Great PR I think but there is a bug in reading distortion parameters. Please follow the issue: #794

Thanks for your suggestion, but we have already corrected the parameter index in our code. Could it be that you are using an earlier commit?

# SIMPLE_RADIAL:      f, cx, cy, k
if type_ == CameraModelId.SIMPLE_RADIAL:
    params = np.array([cam.params[3], 0.0, 0.0, 0.0], dtype=np.float32)
    camtype = "perspective"
# RADIAL:             f, cx, cy, k1, k2
elif type_ == CameraModelId.RADIAL:
    params = np.array([cam.params[3], cam.params[4], 0.0, 0.0], dtype=np.float32)
    camtype = "perspective"

[MomokoMatsuo]

Ah I'm sorry I was using the old version. I noticed the bug was already fixed. Thank you! @npu-chenlin

[ssheorey]

Thanks @npu-chenlin This PR allows simple_trainer.py to work in Windows. With the SceneManager pycolmap, we get errors loading the Linux COLMAP data in Windows.