PyGEL3D 0.0.22

PyGEL 3D (Python Bindings for GEL) contains tools for polygonal mesh based geometry processing

INTRODUCTION

GEL is a C++ library of geometry processing tools intended for computer graphics applications. In particular, GEL contains a fairly mature half-edge based library, an efficient kD tree and data structures for volumetric data. Functionality includes quadric based simplification, mesh optimization, distance field computation, iso surface polygonization and more. A linear algebra library for small vectors and matrices is also included as well as tools for visualizing meshes using OpenGL.

PyGEL3D is a set of Python bindings for a subset of the features in GEL. In particular, PyGEL covers almost all the mesh features. In addition PyGEL has its own viewer based on OpenGL and PyGEL can be used from Jupyter notebooks. In this case, it is possible to visualize meshes using a plotly widget. A significant benefit here is that when the notebook is exported to HTML, the 3D view comes along.

DOCUMENTATION

Some installation instructions below. But for more documentation please see the doc directory. There is a doxygen script for creating a reference manual and a latex file intro.tex which explains the basics. Please doxygen or pdflatex your documentation. A license is also found in the intro document.

Building on XCode/OSX

An XCode project has been created and is found in the GEL_MAC directory. The XCode project produces a framework for the GEL library. There are also Xcode projects for the demos and for PyGEL. However, if you want to install PyGEL as a wheel package, you shoud use CMake as discussed below.

Building on Windows

A Visual Studio solution has been created and is found in the GEL_WIN directory. The project produces a framework for the GEL library. Look in the doc folder for installation of glut and glew

Building on Linux

The CMake files (see below) work cross platform. There are also some scripts for building GEL in GEL_UNIX. However, these are not actively maintained. We recommend using CMake (see below).

Building with CMake

There is a basic CMakeLists.txt - it compiles the GEL library and the PyGEL library but not the demos. You will need to have OpenGL and GLFW3 installed. On windows CMake does not check for the presence of GLFW, but it should work if the files are in standard places. On MacOS and Linux issue the following commands to compile:

#$> mkdir build; cd build; cmake ..; make -j8 ; cd ..

Creating a PyGEL3D package and installing it

to create a wheel package for PyGEL3D that works with Python 3, you can next issue the command

#$> python3 setup.py bdist_wheel

Install using something like

#$> sudo -H pip install dist/PyGEL3D-*.whl

For this to work, you need to have wheel and setuptools installed.

Requirements

Compiling both GEL and PyGEL requires that you have OpenGL and GLFW installed unless you choose not to compile graphics support which you can do by setting Use_GLGraphics to OFF in the CMake file. If you compile elsehow (e.g. using XCode, Visual Studio) there is no simple way to avoid these requirements. Thus, if you need to avoid the OpenGL requirements, CMake is the way to go.

GEL comes with a few demo applications. In addition to the requirements above, these also require GLUT to be installed. Going forward, we should remove the GLUT dependency and move to GLFW for the applications.

PyGEL3D has a module called 'js' which produces graphics suitable for Jupyter notebooks. This module is based on plotly which must then be installed for it to work. You will also need numpy. However, these required libraries will be downloaded when you install PyGEL3D if you use pip.