FractalBasic

using UnityEngine;
using System.Collections;

public class FractalBase : MonoBehaviour {

    Texture2D texture;

    public int resolution = 128;
    public int maxIterations = 1000;

    public Gradient g;
    public GradientColorKey[] gck;
    public GradientAlphaKey[] gak;

    public float zoom = 1f;
    public float xShift = 0;
    public float yShift = 0;
    public float moveSens = 10;

    void Awake ()
    {
        texture = GetComponent<Texture2D>();
    }

    void Start()
    {
        texture = new Texture2D(resolution, resolution);
        texture.name = "MandelTexture";
        UpdateTexture();
        GetComponent<MeshRenderer>().material.mainTexture = texture;
    }

    void Update()
    {
        //navigation stuff
        if (Input.GetButtonDown("Fire1"))
        {
            float s = moveSens * zoom;
            Vector2 v2 = Input.mousePosition;
            xShift += (v2.x - Screen.width / 2) / s;
            yShift += (v2.y - Screen.height / 2) / s;
            texture = new Texture2D(resolution, resolution);
            UpdateTexture();
            GetComponent<MeshRenderer>().material.mainTexture = texture;
        }
        float z = Input.GetAxis("ZoomAxis");
        if (z != 0)
        {
            zoom += z * 10;
            texture = new Texture2D(resolution, resolution);
            UpdateTexture();
            GetComponent<MeshRenderer>().material.mainTexture = texture;
        }
    }

    void UpdateTexture()
    {
        for (int x = 0; x < resolution; x++)
        {
            for (int z = 0; z < resolution; z++)
            {
                //called for every pixel on the quad
                CalcMandelbrot(x, z);
            }
        }
        texture.Apply();
    }

    //where the magic happens
    void CalcMandelbrot(int row, int col)
    {
        float re = (((row - resolution / 2.0f) / zoom) + xShift) * 4.0f / resolution;
        float im = (((col - resolution / 2.0f) / zoom) + yShift) * 4.0f / resolution;
        float x = 0, y = 0;

        int iteration = 0;
        while (x*x + y*y <= 4 && iteration < maxIterations)
        {
            float x1 = x * x - y * y + re;
            y = 2 * x * y + im;
            x = x1;
            iteration++;
        }
        if (iteration < maxIterations)
        {
            texture.SetPixel(row, col, g.Evaluate((float)iteration / maxIterations));
        }
        else
        {
            texture.SetPixel(row, col, g.Evaluate(1));
        }
    }

    float Norm(Vector2 v2)
    {
        return v2.x * v2.x + v2.y * v2.y;
    }
}