The ebuild required dev-python/wxpython as an RDEPEND which is incorrect. Either Qt4 or WxPython can be used. Attached below in the comment section is a patch to correct this. Reproducible: Always Steps to Reproduce: 1. emerge mayavi 2. 3. Actual Results: Failed to build do to the wxGTK dependency refusing to build
Created attachment 206517 [details, diff] Fixes broken ebuild wxpython should be included as a USE flag and should be optional as an RDEPEND. Qt4 _or_ WxPthon can be used.
There is already global "wxwidgets" USE flag, which can be used for this package.
mayavi used to require wxpython even when the qt4 widget was selected (bug #266799). Have you actually checked upstream the qt4 backend to be independent?
The patch proposed won't resolve the issue. This is an upstream problem, they need to provide a wxwindows free version of mayavi2.