Since it took me a while to figure out, heres a .travis.yml file which you can use to configure Travis. It downloads and installs a panda3d development build on ubuntu, and then runs main.py:
language: cpp
sudo: required
dist: trusty
compiler: gcc
addons:
apt:
sources:
- sourceline: "deb http://archive.panda3d.org/ubuntu/ trusty-dev main"
packages:
- cmake
- libeigen3-dev
- libfreetype6-dev
- panda3d1.10
script:
- export PYTHONPATH=${PYTHONPATH}:/usr/lib/python2.7/dist-packages
- export PYTHONPATH=${PYTHONPATH}:/usr/share/panda3d
- python2.7 main.py