Perlin Noise in Godot – Go Programming Language

Perlin noise is a technique used in computer graphics to produce natural-looking textures, animations, and landscapes. It is a type of gradient noise that was developed by Ken Perlin in 1983. In this article, we will discuss how to use Perlin noise in Godot, a popular game engine. We will be using the Go programming language to implement the algorithm.

What is Perlin Noise?

Perlin noise is a type of gradient noise that generates a sequence of arbitrary values that appear random but are actually coherent (i.e., they follow a pattern) at different scales. The resulting noise can be used to create textures, animations, and landscapes that look natural.

The algorithm generates random vectors at each lattice point and takes a dot product of these vectors with the position of the point. The dot products are then interpolated to produce smooth transitions between values. The result is a value that varies from -1 to 1.

Using Perlin Noise in Godot

Godot is a popular game engine that supports a variety of programming languages, including Go. To use Perlin noise in Godot, we need to generate a noise map and apply it to a texture.

First, we need to download the Go bindings for Godot. We can do this by running the following command:

go get -v -u github.com/godot-go/godot-go/cmd/godot-go

Next, we need to create a Godot project and add a script to it. In the script, we will use the Module interface to create a NoiseMap and apply it to a texture. Here's an example:

package main

import (
    "github.com/godot-go/godot-go/pkg/gdnative"
    "github.com/godot-go/godot-go/pkg/gdnative/gut"
    "math/rand"
)

func main() {
    gdnative.RegisterInitCallback(gdnative.InitCallbackFunc(func(_ gdnative.CoreAPI) {

        gut.PackedSceneRegister("res://scenes/NoiseTexture.tscn")

        gdnative.RegisterClass(
            "NoiseTexture",
            gdnative.NewClassBuilder(&NoiseTexture{}).
                WithParent("Texture").
                WithMethod("GenerateNoise", gdnative.MethodAttrs{RPCMode: gdnative.RPCModeDisabled}, generateNoise).
                Build(),
        )

    }))
}

type NoiseTexture struct {
    gdnative.TextureImpl
}

func generateNoise(_ *gdnative.Object, _ *gdnative.MethodArguments) (*gdnative.MethodResult, error) {
    // Get texture size
    width := 512
    height := 512

    // Create noise map
    noise := make([][]float64, height)
    for i := range noise {
        noise[i] = make([]float64, width)
        for j := range noise[i] {
            noise[i][j] = rand.Float64()*2.0 - 1.0
        }
    }

    // Apply noise map to texture
    b, err := gdnative.GodotVariantFromAny(noise)
    if err != nil {
        return nil, err
    }
    gdnativeTexture, _ := _.(gdnative.Texture)
    gdnativeTexture.SetData(noise)

    return gdnative.NullVariant, nil
}

In the script, we create a new NoiseTexture class that extends the Texture class. We also define a GenerateNoise method that creates a noise map and applies it to the texture.

Conclusion

Perlin noise is a useful technique for generating natural-looking textures, animations, and landscapes. With the help of the Go bindings for Godot, we can easily use Perlin noise in Godot. In this article, we discussed how to generate a noise map and apply it to a texture using the Go programming language.