HeightMap.java

package de.syscy.engine.world;

import de.syscy.engine.components.GameComponent;
import de.syscy.engine.core.Vector2f;
import de.syscy.engine.core.Vector3f;

public class HeightMap extends GameComponent {
    public static final int WIDTH = Chunk.WIDTH;
    public static final int LENGTH = Chunk.LENGTH;
    float[][] height;

    private Noise noise;
    private float noiseFactor = 60;

    public HeightMap(Vector3f pos, Noise noise, Vector2f cID, float noiseFactor) {
        setName("heightMap" + cID.getX() + "," + cID.getY());

        this.noise = noise;
        this.noiseFactor = noiseFactor;

        try {
            height = new float[WIDTH][LENGTH];
            for (int x = (int) pos.getX(); x < WIDTH + pos.getX(); x++) {
                float noiseX = (float) x / noiseFactor;
                for (int z = (int) pos.getZ(); z < LENGTH + pos.getZ(); z++) {
                    float noiseZ = (float) z / noiseFactor;
                    float noiseValue = (float) noise.noise(noiseX, noiseZ);
                    height[(int) (x - pos.getX())][(int) (z - pos.getZ())] = noiseValue;
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public float getHeightAt(int x, int z) {
        try {
            return height[x][z];
        } catch (Exception e) {
            float noiseX = (float) x / noiseFactor;
            float noiseZ = (float) z / noiseFactor;
            float noiseValue = (float) noise.noise(noiseX, noiseZ);
            return noiseValue;
        }
    }

    public float calculateHeight(float x, float z) {
        float x1, x2, y1, y2, Q11, Q12, Q21, Q22;
        x1 = (int) Math.floor(x);
        x2 = (int) Math.floor(x + 1);
        y1 = (int) Math.floor(z);
        y2 = (int) Math.floor(z + 1);

        Q11 = getHeightAt((int) x1, (int) y1);
        Q12 = getHeightAt((int) x1, (int) y2);
        Q21 = getHeightAt((int) x2, (int) y1);
        Q22 = getHeightAt((int) x2, (int) y2);

        return (1f / ((x2 - x1) * (y2 - y1)))
                * (Q11 * (x2 - x) * (y2 - z) + Q21 * (x - x1) * (y2 - z) + Q12
                        * (x2 - x) * (z - y1) + Q22 * (x - x1) * (z - y1));
    }

    public float calculateHeightRounded(float x, float z) {
        return getHeightAt(Math.round(x), Math.round(z));
    }

    public void dispose() {
        height = new float[1][1];
    }
}