Unreal Engine only uses VS as an editing/debugging platform. They have their own build system (UnrealBuildTool) which does the actual build. So it should be possible to setup Eclipse or Code::Blocks to use it. The only other VS dependecy is the project generators and if your IDE of choice supports import VS solutions, this should be easy to do. There was someone who got thinks working with QT Creator, do a search of the board for the threads.