Making changes to engine's C++ code

Hello everyone, I have been trying to figure out some of the math behind the foliage placement with the foliage brush, so I went into the engine folders, and opened up a C++ file that contained the code that I was looking for, so I made a few changes, and then saved the file, but when I was using the foliage brush, it was as if the changes were never applied. Is there anything special I need to do to use the modified C++ file after I save it?

I am really no c++ expert, but have you recompiled the engine? This always takes some hours for me an you have not mentioned it, just saving a c++ file does not change the compiled executable.

I have not nor do I know how to recompile the engine, if it takes hours, it doesn’t seem like it’s really worth it just for a minor math change :\

If you are in visual studio, just right click on “UE4” in the top left and click “build”. I don’t know whether it takes hours for you too, maybe you have a better CPU than me and it’s faster for you :slight_smile:

Alright, but first, what happens if it does end up taking hours and I want to cancel it? (I just have a quad-core AMD)

There is a cancel button of course, but I don’t know where exactly :wink:

There is a cancel button in the BUILD menu. But has anyone gotten it to work yet? See my thread here: How to cancel/abort a build? (Visual Studio 2013)