Mayavi is based on VTK, which is a C++ toolkit for data visualization. It's both an advantage and a drawback, depending on your needs. The good thing is that VT

Mayavi is based on VTK, which is a C++ toolkit for data visualization. It's both an advantage and a drawback, depending on your needs. The good thing is that VTK is solid and if you're familiar with the concepts, it can be powerful, but it's also somewhat complex. On the other hand, the python (traits) wrapper around VTK that mayavi is built upon adds another layer of abstraction and changing things that aren't directly exposed by mayavi is difficult. From a quick look, vispy seems to be built directly on OpenGL and numpy, so I think it will be easier to customize. But the devs will have to rewrite a lot of what VTK provides. It also aims at providing an integration in ipython notebook (with WebGL), which is awesome :)