Vector/Coordinate Expressions in Unreal - seeking advice

Hey Guys,

sorry for another thread, but since my last questions already pointed me towards tons of info and gave me the examples i was looking for i hope someone can assist me in this case as well!

I am having a lot of trouble understanding the Vector and Coordinate Expressions that you use in the Unreal Editor.
I am learning a lot from Jeremy Baldwins EAT 3D FX Masterclass and i understand the “common” stuff he does, like multiplication, lerping, add, sines, panning, etc.

But some things i cannot work with as in i dont have any idea how and especially why he does something. That also goes for the free Unreal videos on EAT3Ds vimeo.

Anyhow - to give you a basic idea. Often you have him subtracting the world position by the object position, or dividing those. Or you have him transform the world space into the object space. Or doing some mathematical operation on the camera vector or camera position. Or something with the View Size. (So everything vector/coordinate related)

I kept the examples fairly basic (some of them might even be wrong, since i am writing off the top of my head) because i hope some of you guys can point me somewhere where these things are explained or even demonstrated or heavily used - anything like that.

I already checked the Unreal docs, but honestly most expressions only have one or two senteces describing them and it is pretty unspecific.

I hope someone can steer me in the right direction! If you would like some exact examples i can check some of the videos again and write them down by tomorrow! But i hope i can get some info on how and when to use these expression in general and not only for specific examples.

Anyhow - i hope i gave enough info for a start. But this is driving me a little nuts.

Cheers xD!

Brush up on your linear algebra and you’ll be fine.


What helps me understanding those things is really testing them in materials and meshes, just really plugging everything everywhere. For example, you can plug an Object Position and a Camera Position into a Distance node and use that to drive some effect.

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Yeah, Khan Academy is great and i recently started brushing up on my math :smiley:

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Hi Bruno!

Yes, i thought the same and played around with some of the nodes to see what kind of changes happen in the view port. With simple stuff like transforming the world space to object space i even get what is happening.
But i had hoped there might be a site or a course that also deals with these kind of technical things a little more.

In this particular DVD the author never really mentions why he does something. But with most stuff it is pretty self explanatory. (like the non world position transform etc. stuff)
But even knowing that it is usually used to drive some position based effect there are so many ways to calculate them together :sweat:

Look at how other people do it and it might give you some ideas :slight_smile: Check this out for example:

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