SWC file may be huge due to redundancy of points when build. Currently, there is a resample plugin to reduce the number of point by down sampling. However, this down sample process based on fixed steps. This will not be nice when neuron turns in sharp angle as it will over smooth the structure. It will be better to add a adaptive threshold method for better visualization.

Adaptive down sample feature is now updated.
1. The down sample decision is made based on turning angle of curves. If the curve turn sharply, the point will be kept. Otherwise deleted.
2. Radius change is an optional criteria when perform down sampling. If option checked, the point will be kept when radius changes sharply.
3. An optional re-sample can be performed before down sampling. This will uniform the length of segments on curves and smooth the curves a little bit. This will help to remove unexpected short sharp turning or zigzag that may impact the performance of down sample.
4. All input parameters required can be set in a simple dialog.

The path problem has been fixed. Relative path is applied.

need to fix the path to make it general on any platform

work/vaa3d_tools/hackathon/hanbo/resample_swc_adapt/resample_swc.pro:5: Unescaped backslashes are deprecated.
WARNING: Failure to find: d:v3d_main/basic_c_fun/v3d_message.cpp
WARNING: Failure to find: d:v3d_main/basic_c_fun/basic_surf_objs.cpp

It is not thresholding, it is resampling.