Shapable terrain in Unity3D?

Question

I want to make a shapable world (and maybe also procedurally generated), but I don't know how to make it via script.

There are a few examples whom I have a few questions about:

Minecraft

It is easy to make a procedurally generated shapable world from cubes, but I don't know how to make it optimal. Does unity strong enough the handle a lot of cubes?

Landmark

In this game you can shape the world and it uses Unity like terrain. It's is similar to Minecraft but it's not as cubic. (So when you dig in the ground, you dig ~like in real life. So you don't dig cube by cube like in Minecraft)

Is it possible to shape the terrain runtime?

Thanks for your help in advance!

Answer 1

It is easy to make a procedurally generated shapable world from cubes

Short answer, no it is not easy. You would have to use some type of noise to generate a heightmap (like voxel noise, here's a blog tutorial)

[Is] unity strong enough the handle a lot of cubes?

No, on it's own unity will not handle the amount of cubes needed for a minecraft clone very well. Statistically speaking you will never be able to see all 6 faces of a cube, so rendering all 6 is wasteful. Also, each cube will have it's own collider which will quickly clutter. Also you do not need to render a cube if it is blocked by other cubes. All this requires complex optimization code to make it run efficiently as you are modifying the terrain and moving through the world.

Is it possible to shape the terrain runtime?

Yes, here's some code I stole from this question:

function Start()
{
    terrain = GetComponent(Terrain);
    var nRows = 50;
    var nCols = 50;
    var heights = new float[nRows, nCols];
    for (var j = 0; j < nRows; j++)
        for (var i = 0; i < nCols; i++)
            heights[j,i] = Random.Range(0.0,1.0);
    terrain.terrainData.SetHeights (0,0,heights);
}

and here's the documention on TerrainData.SetHeights()
https://docs.unity3d.com/ScriptReference/TerrainData.SetHeights.html