@Patrice : I use code::block for Linux, I think it's open source but for Windows and Mac, I'm too many attracted by the comfort of XCode and Visual Studio... Anyways, a good Makefile is the solution ! For GUIs, I create a canvas in a window, the best way to clip drawing and to receive all the modifiers, keys, etc. I'm also working an a good documentation of the code, others developers will be able to create externals with this library.
@IOhannes : I explain in @chocolate.pd, you should be in edit mode to popup the menu (I hope it works on your Linux distrib). If I overwrite the classes, the users won't be able to create the vanilla object.
Thank a lot !