Hi Gergely, I think you do not need the source code at all if your C++ touch library is wrapped for use from Python. All of the Chimera Python code is included in every Chimera distribution (look in chimera/share). The Python that handles the normal Chimera mouse modes (rotation, translation, zooming) is in chimera/share/chimera/tkgui.py. Look for the _mouseFuncs table at about line 2300. The mouse buttons can be reassigned to any function and this _mouseFuncs table gives functions that get invoked on mouse down, mouse drag and mouse up events. You can get the entire Chimera source code. It is available on the Chimera web site: http://www.cgl.ucsf.edu/chimera/sourcecode.html I've added today's source code to the web page and it will appear tonight when our web pages are rebuilt. Compiling it depends on getting about 35 third-party packages to compile, so you definitely do not want to try compiling it if that can be avoided. We have compilation of all those libraries automated on specially setup machines (operating systems, cpu architectures, developer tools installed, ...) and it can be a lot of trouble to get it to work on a new system. Tom