I built the engine from 4.13 branch. It built ok and I was able to open and package an Android project. The problem is it takes much longer to package. While on launcher version it performs 11 actions (the ones that appear as [1/11] clang++.exe …), on the source binary it performs 200+ actions, everytime. Why is that?
in source version there is not binery android build so it needs to build it and if you put “Full Rebuild” it will rebuild fully together with engine, with launcher version it rebuild as it does not have source will only rebuild your code. UBT generally considers engine code as part of your project, in the past when there was no project system (UE3 and ealier) you made game by extend the engine and technically it still is, project system was made just so you don’t need to have n copies of huge engine for n number of projects.
Use “full rebuild” only when packaged version start to behave strange (has partly new and partly old code or starts to throw some strange errors) and when you make you release build so it will use existing already build engine object files insted of making them again by recompiling them
It all makes a lot of sense! I started to do like you suggested: only use Full Rebuild if weird ■■■■ happens. Using the source is just temporary, though. As I’m just waiting for a fix to be implemented on release version. Likely, on next preview.