Variable-width-contouring

Code for computing beads (aka toolpaths, print-paths, print-trajectories) in a slice with varying width for minimizing underfill. This is the code developed for the publication

Variable-width contouring for additive manufacturing. Samuel Hornus, Tim Kuipers, Olivier Devillers, Monique Teillaud, Jonàs Martínez, Marc Glisse, Sylvain Lazard and Sylvain Lefebvre. ACM Transactions on Graphics 39(4) (Proc. SIGGRAPH 2020) [link]

Visualization and analysis

Code and scripts for visualizing and analyzing variable-width GCode can be found here.

Authors of the code

• Samuel Hornus (Inria, France)
• Tim Kuipers (Ultimaker, TU Delft, Netherlands)

Salim Perchy and Pierre Bedell also contributed to Windows- and plugin-specific code.

Compilation dependencies

For compiling the fill binary:

• CMAKE
• TCLAP http://tclap.sourceforge.net
• Clipper http://angusj.com/delphi/clipper.php
• If the VWC_USE_CGAL_MEDIAL_AXIS CMake option is checked, then the code depends on CGAL https://www.cgal.org
• If both the VWC_USE_BOOST_MEDIAL_AXIS and VWC_USE_EXTERNAL_BOOST CMake options are checked, then the code depends on BOOST
• If the VWC_USE_CAIRO_PDF CMake option is checked, then the code depends on Cairo https://www.cairographics.org

For compiling the IceSL plugin:

If the VWC_MAKE_ICESL_PLUGIN CMake option is checked, then the plugin libVariableWidthContouring.so is compiled. This needs the icesl-interface library sources to be copied (typically as a git repoitory) alongside the src directory. (That library sources is not yet publicly available.)

Compiling

It should work alright on macOS and Ubuntu.

mkdir build
cd build
cmake ..
make

You may have to adjust the CMakeLists.txt. Please send us your pull requests!

There is the VWC_USE_CAIRO_PDFCMake option to disable the use of Cairo. Then no PDF is ever output.

If you compile with both VWC_USE_BOOST_MEDIAL_AXIS and VWC_USE_CGAL_MEDIAL_AXIS then a command-line option -b / --boost is added to choose to use BOOST instead of the default CGAL for computing the medial axes.

Usage of fill

fill -h will give you a a lot of options.

The basic usage is fill -p input_file -o output_file. Without -o just the PDF file input_file.pdf is generated (unless --no-pdf).

Input format

The input_file starts with the minimal and maximal allowed bead width. The rest is a sequence of polygonal closed curves. Each curve starts with the number of sample points (on one line). Then there is one sample per line. Each sample gives x, y.

Output format

The output_file is a (textual) sequence of print paths. Each print path start with the number of samples. Then there is one sample per line. Each sample gives x, y, radius (half width), tangent_x, tangent_y.

Dataset

The input/ directory has some sample input files.

The set of 300 input files in input/dataset/ is the one used in the paper and originates from the following work:

A framework for adaptive width control of dense contour-parallel toolpaths in fused deposition modeling. Tim Kuipers, Eugeni L. Doubrovski, Jun Wu, and Charlie C. L. Wang. 2020. Computer Aided Design, vol. 128. arXiv, DOI.

Generating lots of output

You can use this simple shell command:

for f in `ls ../input/*.txt ../input/dataset/*.txt`; do ./fill -p ${f}; done

This will generate one PDF file and store it alongside each input file. Each page shows the state of the medial axis and the new bead.

Usage of the IceSL plugin

Copy the file libVariableWidthContouring.so into icesl-plugins/ directory.