Graveyard Keeper: How the graphics effects are made
>The problem “how to find the closest 3 light sources and to calculate the distance and an angle was solved with a script running in the Update() loop.
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> Yes, it’s not the quickest way considering how much math is involved. If I programmed it today, I would use that modern Unity Jobs System. But when I did it there was no such thing so I had to optimize regular scripts we had.I wish they'd let you in on a little more.  Because my numb mind says this isn't something you should ever need to optimize.  How many light sources do they have, dozens at most?  And how many sprites?  Dozens/hundreds?  That is nothing.. what is this heavy math?  I figured all they'd need is a vector from light source to object, and the vector's magnitude.