Why rebuild the entire UE4 when I build my project?


I couldn’t find a solution in the forum, I’m sorry if it has been asked before :frowning:

These are my specs:

  • Windows 8.1 Update 2 fully updated
  • Visual Studio Ultimate 2013 Update 3
  • UE 4.4

I’ll tell you what I did step by step:

  • UE 4.4, compiled from source in my secondary HDD
  • Double click on the generated .exe
  • The editor opens, create new project, c++ third person (the project is in a different folder in the same HDD)
  • The solution contains my project, plus the UE4, plus a bunch of other stuff
  • Set DebugGame_Editor x64 Mode
  • Right click on my project, build, VS recompiles everything, 30 minutes of time wasted
  • Unload all projects but mine
  • Add a class, build, VS recompiles everything, 30 minutes of time wasted
  • Delete all projects but mine, make some changes, build, VS recompiles everything, 30 minutes of time wasted

I’ve tried other things, but I think you get the point.

I don’t wanna rebuild the UE4 ever again in my life if I don’t change it, how can I do that?

Thank you

p.s. Attached there’s my last compilation output of a super simple project that follows the Battery Tutorial

the recompilation is done only once make sure of the following : either set your project as start up project (by right clicking on it and set up as start project) also make sure to remove engine and program folder under your solution , this will make sure it compiles ur project , and not ur engine.

I’ve already did both things and still, the engine gets recompiled.

Does your engine build solution configuration match your games one? Fe. have you built the Engine in Debug - Win64 and Debug Editor - Win64 when you want to use your Game in Debug config? I think if they dont match it will recompile all. And take care what you click, “Rebuild” your game will lead to rebuild everything. Look at my answer here Problem: The engine compiles every time we do changes to our project - C++ Gameplay Programming - Unreal Engine Forums. Im sorry if you did all that and it does rebuild anyways, I wouldnt know how to help further. I hate that the engines build system wants to rebuild everything on all thinkable occasions too. Lost so many hours waiting…

Mmmhh… the Engine is builded with Development Editor and the game project uses DebugGame Editor. I did as the tutorial said, I suppose that DebugGame is needed if you want to debug your game, but not the editor, am I wrong?

I’ve tried to create a new class from the editor and it did, but it re-added the Engine and the other programs. It’s probably pointless remove them again.

One thing I noticed are the Project dependencies, I removed them from my game project, I’ll try to see if that helps

I will also try to compile everything with Development Editor.

So far seems to be working, not quite sure for what reason. Mikand79 might be right, but I think that’s not the only reason otherwise it should have had compiled just the first time. If I’ll find out something more I’ll write an update here.

Thank you all guys

Development isnt perfect for debugging but it should work out quite good. My call stacks and variable display in the debugger was good enough yet. If it fails just build the Debug version.

Its easy to think Visual Studio is managing your sources, but its not. Its used by UE4 as a fancy editor and debugger, the build management is done solely by UnrealBuildTool.exe, thats why it doesn’t matter if you remove projects and they still get build if UBT thinks its an awesome idea.