How exactly is Perlin Noise implemented?

main way perlin noise implemented is to generate SAME noises on different targets. for example, to cover some surface without using a texture and be sure that t$$anonymous$$s surface will look same on every generating and on every client it generates.

so in your case you can use simple UnityEngine.Random to got all randomization you need. heightmap, box placing, painting etc - just write algorithms to apply random to your world

Your boxes will have x and y coordinates. Since most perlin noise functions take 1 parameter, use some hash function that takes your x and y values and then pass the hash to the perlin noise function. T$$anonymous$$s will give you a height. Unfortunately, the heightmap isn't going to be very smooth, so you should do some interpolation and smoot$$anonymous$$ng of the nearby values. T$$anonymous$$s article explains that process fairly well (see the paragraph "2-dimensional Smooth Noise").

You want an example for a Minecraft like terrain generator? Just take a look at the Minecraft starter package for Unity. It contains all you need.

http://answers.unity3d.com/questions/188721/creating-perlin-noise.html#answer-383517 ^^ those are tests i just did on the unity perlin function. image and distribution data. see end of thread.