/Smooth-Feature-Lines-Extraction

This is the final project for the course CSCI-GA-3033-018 Geometric Modeling at NYU

Primary LanguageC++

Build Status

Smooth Feature Lines on Surface Meshes

-- based on the paper by K. Hildebrandt, K. Polthier and M. Wardetzky

Background

Feature lines on a mesh carry the visually most prominent characteristics of the mesh. This paper introduces a way to detect the feature lines on a mesh based on utilizing discrete differential operators on piecewise linear meshes.

Objective

  • Detect “salient ridges” on meshes
  • Compute points with extreme principal curvatures
    • Under certain conditions, these form feature curves
    • Checking these conditions requires computing 1st and 2nd derivatives of curvatures

Procedures

  • Compute principal curvatures
  • Compute discrete extremalities
  • Smooth discrete extremalities
  • Determine regularity for each triangle
  • Trace feature lines in regular triangles
  • Process singular triangles

Library used

  • Libigl

Results

  • Direction of principal curvatures on a half cylinder image
  • Color map of the extramalities on a bumpy cube
    • e max (absolute values) image
    • e min (absolute values) image
  • Singular triangles on a hand image
  • Feature lines
    • on a camel head image
    • on a bumpy cube image
    • on a bumpy plane image

Todo

  • Remove small ridges by a threshold