# A few unrelated questions

Is there a simple way to take an array of actors and choose the closest one to the player for a given function? I made a really complicated blueprint to do this but it’s not flexible and appears to perform the task slowly, so I want to figure out a simpler, better, faster way if possible.

How do I make a ragdoll hang from one joint? I want to simulate a ragdoll being suspended in the air and flung around while being held at the pelvis, and from what I’ve tried a simple parenting doesn’t do.

What takes more processing power in a material, compositing using a LERP(Linear interpolate) node or a Multiply node? This is of course when you could perform either for the same effect.

What’s the difference between a skylight and a light source? The default maps have both and I’m not sure why.

How much of my game should I expect to break if I upgrade it from 4.8 to the current version?

i’m not good enought at unreal to answer all your questions, i had to calculate distance between points in one of my blueprints, and i don’t know a short way to do it, to find the closest actor i would do the “complicated blueprint” way, do a foreach loop, create 2 temporary variables(one for the the actor who is winning the “closest competition” till now, and other to store the distance between them (to avoid recalculate) , get the position of the two actors you want to calculate distance and calculate the distance with square root of((x1-x2)²+(y1+y2)²+(z1+z2)²), pay attention to the initialization of the variables, you’ll have to initialize them with the first actor in the “foreach loop”, since the first actor will be the closest at this point (you’ve not compared him with anyone yet, so he is winning) if you don’t do this unreal will initialize the variable you’re using to store the distance with 0 (by default) and you won’t find a distance <0 so your loop would be useless.This isn’t the “simpler, better, faster” way you wanted, but it should work, and it’s something.

about the skylight, you find some explanation about how it works in the “twin stick shooter tutorial” video, not sure what video, i remember he explained what it is and how it works when he was creating the map, probably in one of the first 3 videos.