Hey!
I had the same problem with the 4.1 version of the engine. It got solved, now we have the 4.2 version and it’s back again. I am just sitting here, playing with the material editor tools and the engine compiles thousands of shaders…
I watched the video and can see what you mean! Did this start occurring immediately after 4.2? Does this occur in a clean project with no additional content?
I am not sure I think this type of the bug was present in 4.1.1 too, I think they just removed that, it gets compiled if you add constants and so on. Unfortunately I didn’t work a lot with 4.1.1, I just recognized that the old bug was gone.
I saw today that it happens when I add devide, multiply and these components… and the absloute world position component… probably it happens with a lot more components, but these are the ones which I know who cause the material to compile.
Okay, I think I solved the problem for me. At the moment it works, I had to deactivate the real time protection of GData for the engine. I guess while it’s compiling shaders the engine changes a lot of files, which causes GData to slow everything down.
Short: GData is an antivirus program, it’s real time protection is checking the files while the engine is compiling to make sure that everything is alright. This slows the whole system down, because it uses around 60% of the CPU. It’s unusual for GData to cause problems, due to that fact I didn’t think about it earlier.