Procedural terrain perlin noise

Scripting Issues
1

Hello everyone, i want to generate realistic procedural heightmap, i use perlin noise algo for this.
But i have problem, i have a random terrain, not “realistic” with not river, sea, mountain…

1*vs239SecVBaB4HvLsZ8O5Q.jpg1200×1200 234 KB 

import sys
from noise import pnoise2, snoise2


Xstart=0
Xend=0

for i in range(0,2):
name="./heightmap"+str(i)+".pgm"
print(name)
f = open(name, 'wt')
octaves = 10
freq = 16.0 * octaves
f.write('P2\n')
f.write('256 256\n')
f.write('255\n')
Xend=Xend+256
for y in range(0,256):
    for x in range(Xstart,Xend):
        f.write("%s\n" % int(snoise2(x / freq, y / freq, octaves) * 127.0 + 128.0))
f.close()
Xstart=Xstart+256
print(Xstart)
print(Xend)
print("...")

would you have better to offer me?

2

You need more then one frequency, noise in different scales and more often then not some manipulations of the noise values.
Try this:


Its a simple random terrain generator, that I once made for a level editor but never integrated it, the noise generation runs on the gpu but the idea is the same. Run it with “main.py -edit” to get a preview and some sliders to edit the shape. You may need to add parentheses to print if you’re on python3

3

In order to get realistic terrain with valleys, rivers, etc. you’ll need to simulate some form of erosion.

This is an example of an algorithm that isn’t too difficult to implement: codeflow.org/entries/2011/nov/10/webgl-gpu-landscaping-and-erosion/
which is based on this paper:
https://otik.uk.zcu.cz/bitstream/11025/5963/1/F23.pdf

4

thanks wezu

i have question, in my first code, i generate 2 small terrain that fit together like a puzzle
I’d like to do the same with your code

when define your varaible self.size, i want to define in x axis for fist terrain 0-512 size and for seconde 512-1024

it’s possible to make this with make_buffer to define a zone to draw ?

self.erosion_map=self.make_buffer(Shader.load(Shader.SL_GLSL,'shaders/erode_v.glsl','shaders/erode_f.glsl'), self.size,rgbBits=(16, 0, 0, 0))

like this :

self.erosion_map=self.make_buffer(Shader.load(Shader.SL_GLSL,'shaders/erode_v.glsl','shaders/erode_f.glsl'), [self.size, self.size*2],rgbBits=(16, 0, 0, 0))

5

You could modify that function, you’d need to pass the size to the base.win.make_texture_buffer() function but wouldn’t it be simpler to cut the image into pieces after making the heightmap?

Or you could change your own code, I posted this to show how one can make use of noise to make different shapes, the core of it is in the shaders/noise_f.glsl:

float h=pow(1.0-abs(snoise((uv*parm1.x)+seed1)), 2.0)*parm1.y;
h+=(1.0-abs(snoise((uv*parm2.x)+seed2)))*parm2.y;   
h+=pow(abs(snoise((uv*parm3.x)+seed3)), 2.0)*parm3.y;
h+=abs(snoise((uv*parm4.x)+seed4))*parm4.y;
h+=noise((uv*parm5.x*50.0)+seed5)*parm5.y;
h+=noise((uv*parm6.x*50.0)+seed6)*parm6.y;

All the shapes are made adding up:

pow(1-abs(noise1),2)*a+abs(noise2)*b+pow(abs(noise3),2)*c+abs(noise4)*d+noise5*e

with different values for a,b,c,d,e and a different seed and frequency for the noise.