Bezier

Library for least-square fitting composite Bezier curves.

Features

• Method for least square fitting C¹ continuous composite Bezier curves

• Postscript interface for plotting data points and composite Bezier curves.

Installation

Dependencies

The only dependencies are Eigen (tested with 3.3.4) and cmake.

Install

To install the library into the directory installation run

git clone https://github.com/barkm/bezier.git
cd bezier
mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=installation/ ..
make -j
make install

To uninstall

cd build
make uninstall

Example

The following example generates a postscript file showing data points sampled from a sine wave with a composite bezier curve fitted to the data.

#include <bezier/bezier.h>
using namespace Eigen;
int main(){
  // Generate sin wave data
  ArrayXd theta = ArrayXd::LinSpaced(30, 0, 2 * M_PI);
  ArrayXd sin = Eigen::sin(theta);
  std::vector<VectorXd> data;
  for(int i = 0; i < theta.rows(); ++i){
    data.push_back(Vector2d(theta(i), sin(i)));
  }

  // Fit composite Bezier curve
  bezier::CompositeBezierCurve bezier =
                bezier::fit_composite_bezier_curve(
                                                  data,       // the data
                                                  {9, 19},    // joints
                                                  {3, 4, 5},  // curve degrees
                                                  false       // closed curve
                                                  );

  // Write output to postscript file
  bezier::PostScriptWriter ps_writer(
                                    "example.eps",                                    // file name
                                    {Vector2d(-0.5, -1.5), Vector2d(2*M_PI+0.5, 1.5)} // limits
                                    );
  ps_writer.color(1, 0, 0); ps_writer.filled(true);
  for(const auto & p : data){
    ps_writer.circle(p, 3);
  }
  ps_writer.color(0, 0, 0); ps_writer.filled(false);
  bezier::write_curve(ps_writer, &bezier);
}

If the library is installed in the directory installation, then you should be able to compile the example with

g++ example.cpp -o example.out -std=c++11 -I /usr/local/include/eigen3/ -I installation/include -L installation/lib -l bezier

More examples can be found in the examples directory. Samples can be found in the samples directory.