Random Map Generator Help

Hey everybody my name is Alex..
above you can see my Random Mesh, generated with a Perlin Noise.

Finally my game should be a 2D Game and i want that every Triangle or Vertices that is on the Z axis above a Satic value to show or to delete this point.
It should look like this, to show that i simply added a plane and put it above the Noise Mesh.


And that should be my final Terrain.

Should i check the Vertices or Triangles to achive this terrain?
Sry for my bad English.

 

you need to check the Vertices position, the triangles just store the index of the vertices

 

yeah right, but what should i do when i say that Vertice is under my Borderline and should be deleted?

What i have achived is that all the Vertices that are under 0f should be recalculated and the Y Axis has chanched -2f backwords, that looks really cool, but my questions is, who can i remove those Triangles, so that just the hills are the Mesh?

 

Look at it from the triangles first. Here is what I would do in pseudocode:

make a new list of verts (empty)
make a new list of triangle (empty)
iterate every triangle in the original, considering each point inside the triangle:
-- if all points making up that triangle are below your "zero line," disregard it all
-- if any points are above the zero line:
-- -- add all vertices from this triangle to the new list of verts
-- -- add the triangle (with updated values indexing the new verts obviously) to the new triangle list
update the mesh with the new verts and new tris lists.

Hope this helps!

 

Do you need the mesh? Seems to me like you could simply go straight to setting pixels on a sprite based on the value of the Perlin noise function.

 

or you could set the vertex alpaha but than you need a fitting shader.

but removing the verts is the best methode for perfomance reasons in the long run.

 

i finally made it, but i have a new problem that i want to achive

how can i get a noise that points every Mesh Triangles on the Yaxis and looks smooth to other meshes?? like chunks ^^
pseudocode will do it, hopefully

 

If you use for One Chunk a Noise with a resolution of 1024x1024 make a 4096x4096 Noise for 4 chunks then use it like a atlas for your terrain generation

You can also work with seeds and move inside the Noise

 

Do your chunks have to repeat? You can continue to use Perlin noise offsetting it for each tile to create a non repeating continuous set of chunks.

Or you can use a drop off function on the edges. Corners get a bit tricky this way, but can be done.

 

is it not possible to change the offset of the perlin noise?

I would recommend libnoise for more complex noise effects. There you can just change the offset and seed etc.

 

Sure it is. Here is the full PerlinNoise function with all the adjustments.

Code (CSharp):

1. float noise = magnitude * Mathf.PerlinNoise ((x + xOffset) * xFrequency, (y + yOffset) * yFrequency) + magnitudeOffset;

 

This is my noise function:

Code (CSharp):

1. public float InitNoiseY (int x, int y, float perlinHeight, float xScale, float yScale, int xOffset, int yOffset)
2.     {
3.         float noise = perlinHeight * Mathf.PerlinNoise(Time.time + ((x + xOffset) * xScale), Time.time + ((y + yOffset) * yScale));
4.         return noise;
5.     }

This function is on every chunk:

Code (CSharp):

1. //Add some Noise to the Terrain
2.         if (allowNoiseAdd)
3.         {
4.             for (int v = 0, y = 0; y <= resolution; y++)
5.             {
6.                 for (int x = 0; x <= resolution; x++, v++)
7.                 {
8.                     float noiseY = world.InitNoiseY(x, y, 10f, 0.05f, 0.05f, world.ChunkWidth, world.ChunkHeight);
9.  
10.                     if (noiseY > borderline)
11.                     {
12.                         vertices[v] = new Vector3(vertices[v].x, +0.1f, vertices[v].z);
13.                     }
14.                     else
15.                     {
16.                         vertices[v] = new Vector3(vertices[v].x, -0.1f, vertices[v].z);
17.                     }
18.                 }
19.             }
20.         }

i don't get it :/
this above is my noise function... every chunk is calling it for every vertice, but it looks strange.. how should i use the offset?

 

The offset should be based on the x and y position of the terrain. Basically you want continuous noise from one piece of terrain to the next.