koobas.hobune.stream
Perlin noise sphere
I Have managed to create some random terrain using perlin noise as well as a voxel system, my quetion is how would i make a phere defor using perlin noise, eg a random planet generator :D
Hi,
generally, there are two ways to achieve this:
You need to find a way to map 2D noise to a sphere. There are several methods to do this, but none is perfect, as they will either create distortions or seams or both. The most common methods are described here: http://vterrain.org/Textures/spherical.html I'd recommend a cubic aproach, as the distortions are tolerable and the seams can be worked around.
A noise map on a sphere is possible without seams or distortions, but you need 3D noise for that, as is described here: Improved perlin noise
This kinda answer my Q but when i made a random terrain generator i simply looped from - to the amount of verticies changing there hieght value, but how could this be done with a sphere?
You will need to find a method to translate the 2d height information (the noise) to your sphere. The way to do this depends on the mapping. Take the 'naive' method provided in my first link: The noisemap should have a 2:1 ratio (width to height). At the equator, you take the middle line of this map and project it to your sphere from an arbitrary starting point all around. The same goes for all other vertices except the poles, where all the information of the top and bottom line of your map are projected unto one vertex each (this is the distortion i was talking about). For other ways of projection other methods are necessary.
This is kind of hard to describe in a foreign language. Hope it helps.
I'm pretty sure this is included in the Unity procedural examples asset? http://u3d.as/content/unity-technologies/procedural-examples/3zu
