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# Math Expressions are completely useless..

I don’t have past experience with them but i’ve been told that they’ve been changed to now just create a blueprint graph…

So if you cant do complex math with them nor do they convert a simple text into all these nodes(on purpose of decreasing the size of your blueprint) then whats the point for them to exist?

If it was for making the blueprint more compact, then why not just collapse the nodes(?) So it cant be for that either…

They even increase the size of the blueprint (i tested having normally the math nodes looked at the size and compared it to them being replaced by a math expression and with the math expression it was actually considerably bigger in size.)

They even complicate things, considering that its easier to understand with simple nodes, instead of 1 node having everything in it… & the nodes of the math expression graph are a mess.

So please tell me how they are ANY useful.

I find them quite cool tho.
You can write complex formulas with them pretty easily (you can copy paste external formulas!).
But they could be more handy, indeed. There’s a bug which changes the Name of the Expression to the actual Expression (Expression Name = ABC would mean the Math itself is just a constant with a single input of “ABC”)

They are expressive ie in a glance, you know the formula vs the mormal blueprint (math formula bps can easily get complicated even though they are simple).

• Being able to write formulas instead of having to place a lot of nodes.
• Easily expose float/int inputs in the formula you created by just typing names for them.
• Change the formulas by just typing in the “name” field (which is not a name but the formula itself).

Math Expressions are collapsed blueprint graphs (double click to open it). So no magic here. They are are just shortcuts to make those graphs (tree is regenerated on each rename).

Not gonna lie, would be utterly amazing if UE4 could read mathematical notation and had a basic understanding of common constants. If I could create an expression node, write the expression I wanted, then plug the inputs based on the expression to get my result, I would be simply over the moon. I would pay money for this feature. If I could go on Wolfram, grab an equation, paste it in and run math through it, I simply cannot tell you how disgustingly happy I would be.

I know that will never ever ever happen but… Actually, why couldn’t it be?

May need to talk with someone on my team and see if we can do something with this.

Oh what a good idea.

Yeah good idea. This is what math expressions are already supposed to be… Clearly epic has done a poor job. I guess Math Expressions need a rework.

These are very useful from my point of view. These make math expressions awesome from my point of view.

AND! if you ask me, who is a simple indie dev with simple needs, i think math expressions are the best thing ever in unreal!

You are welcome to make constructive criticism if you think it lacks and please dont dis things saying things like, “its entirely useless”.

I have not tested the size of blueprints, but I have tested performance agaisnt a simple condition, 3 integers a, b ,c… Checked for equality, a == b AND b == c, with normal nodes… Then with math expression (a == b) && (b == c)… Surprisingly the math expression node was faster:

Both scenarios were tested in 4.17.2 in an empty map with just the code actor, in a loop with 100.000 (0-99999) loops:

Scenario 1 (1 condition check per loop):
-RegularNodes : 0.720 ± 0.015
-MathExpression: 0.650 ± 0.015

Scenario 2 (50 condition checks per loop):
-RegularNodes: 2.694 ± 0.028
-MathExpression: 2.413 ± 0.023

Math for the time : ((Highest+Lowest) / 2) ± ((Highest-Lowest) / 2)
Pool: 50 times for each scenario