Wayback Machinekoobas.hobune.stream
May JUN Jul
Previous capture 13 Next capture
2021 2022 2023
1 capture
13 Jun 22 - 13 Jun 22
sparklines
Close Help
  • Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
  • Asset Store
  • Get Unity

UNITY ACCOUNT

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account
  • Blog
  • Forums
  • Answers
  • Evangelists
  • User Groups
  • Beta Program
  • Advisory Panel

Navigation

  • Home
  • Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
    • Blog
    • Forums
    • Answers
    • Evangelists
    • User Groups
    • Beta Program
    • Advisory Panel

Unity account

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account

Language

  • Chinese
  • Spanish
  • Japanese
  • Korean
  • Portuguese
  • Ask a question
  • Spaces
    • Default
    • Help Room
    • META
    • Moderators
    • Topics
    • Questions
    • Users
    • Badges
  • Home /
avatar image
0
Question by Wahoozel · Feb 08, 2015 at 07:36 PM · c#perlin noiseterrain gen

Perlin noise gives the same result every time

I generate random terrain like this:

 void GenerateTerrain(float tileSize) {
     float[,] heights = new float[terrain.terrainData.heightmapWidth, terrain.terrainData.heightmapHeight];
 
     for (int i = 0; i < terrain.terrainData.heightmapWidth; i++) {
         for (int k = 0; k < terrain.terrainData.heightmapHeight; k++) {
             heights[i, k] = Mathf.PerlinNoise(((float)i / (float)terrain.terrainData.heightmapWidth) * tileSize, ((float)k / (float)terrain.terrainData.heightmapHeight) * tileSize) / 10.0f;
         }
     }
 
     terrain.terrainData.SetHeights(0, 0, heights);
 }

But for some reason the terrain never changes. No matter how many times I start the game, it's exactly the same. What can I do to fix this?

Comment
Add comment
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users

1 Reply

· Add your reply
  • Sort: 
avatar image
0
Best Answer

Answer by AlwaysSunny · Feb 09, 2015 at 02:27 PM

PerlinNoise IS always the same every time! (Which can be leveraged to your advantage; for instance, if you needed to reset all changes to the current world, just run the genny again with the same seed).

If you sample the same location with the same scaling, it's the same result each time. To get the randomness you're seeking, you need to inject some randomness into your parameters.

Each time you generate a new world, create a seed (can be an integer, but pick a big one). Use the seed when sampling PerlinNoise:

 ((i / heightmapWidth) * tileSize) + randomSeed

Also, unless I'm misremembering, I think your tileSize variable can be somewhat arbitrary, which will result in a different density of hills and valleys. It's been a while since I worked with that noise class, but I think that's the case.

Good luck,

Comment
Add comment · Share
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users

Your answer

Hint: You can notify a user about this post by typing @username

Up to 2 attachments (including images) can be used with a maximum of 524.3 kB each and 1.0 MB total.

Follow this Question

Answers Answers and Comments

3 People are following this question.

avatar image avatar image avatar image

Related Questions

Difficulty with Perlin Noise based Terrain Generation 2 Answers

Multiple Cars not working 1 Answer

Distribute terrain in zones 3 Answers

perlin noise terrain is spikey 0 Answers

How to handle Perlin Noise ? 0 Answers


Enterprise
Social Q&A

Social
Subscribe on YouTube social-youtube Follow on LinkedIn social-linkedin Follow on Twitter social-twitter Follow on Facebook social-facebook Follow on Instagram social-instagram

Footer

  • Purchase
    • Products
    • Subscription
    • Asset Store
    • Unity Gear
    • Resellers
  • Education
    • Students
    • Educators
    • Certification
    • Learn
    • Center of Excellence
  • Download
    • Unity
    • Beta Program
  • Unity Labs
    • Labs
    • Publications
  • Resources
    • Learn platform
    • Community
    • Documentation
    • Unity QA
    • FAQ
    • Services Status
    • Connect
  • About Unity
    • About Us
    • Blog
    • Events
    • Careers
    • Contact
    • Press
    • Partners
    • Affiliates
    • Security
Copyright © 2020 Unity Technologies
  • Legal
  • Privacy Policy
  • Cookies
  • Do Not Sell My Personal Information
  • Cookies Settings
"Unity", Unity logos, and other Unity trademarks are trademarks or registered trademarks of Unity Technologies or its affiliates in the U.S. and elsewhere (more info here). Other names or brands are trademarks of their respective owners.
  • Anonymous
  • Sign in
  • Create
  • Ask a question
  • Spaces
  • Default
  • Help Room
  • META
  • Moderators
  • Explore
  • Topics
  • Questions
  • Users
  • Badges