How to export correct color after pointcloud sampling?

[zhangzhousuper]

Hi,
I'm experiencing an issue with VertColors after using the makeUniformSampledCloud function. Here's the sequence of events:

I import a pointcloud and successfully store the MR::VertColors vc.
When I export the pointcloud using SaveSettings.colors = &vc, the colors are correct.
After applying the makeUniformSampledCloud function, I export the pointcloud again using the same SaveSettings.colors.
The resulting VertColors in the exported pointcloud are incorrect.
I guess the wrong result comes from the SaveSettings.colors, but I have no idea on how to pass the VertColor to makeUniformSampledCloud function.

Expected behavior: The VertColors should remain correct after the makeUniformSampledCloud operation.
Actual behavior: The VertColors become incorrect after the makeUniformSampledCloud operation.

Please let me know if you need any further information or clarification on this issue.

[Grantim]

Hello!

Basically makeUniformSampledCloud is simpler version of pointUniformSampling that allows to support VertColors:

• makeUniformSampledCloud:
  1. find desired vertices with pointUniformSampling
  2. create new pointcloud from these vertices

What you need to do is to keep only sampled vertices enabled instead of creating new point cloud like this

auto optVerts = pointUniformSampling( pointCloud, settings );
if ( !optVerts )
    return;
pointCloud.validPoints &= *optVerts;

then you can export it and colors should be saved fine