You can use a sum of 4 to 5 sine waves (each with a different amplitude, wavelength and phase difference). All 3 of these parameters may be random.
The resulting curve will be very smooth (since it is mostly sinusoidal), but it will look random (its time period will be the LCM of all 4-5 random wavelengths, which is a huge number).
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public class SineTerm {
private float amplitude;
private float waveLength;
private float phaseDifference;
public SineTerm(float amplitude, float waveLength, float phaseDifference) {
this.amplitude = amplitude;
this.waveLength = waveLength;
this.phaseDifference = phaseDifference;
}
public float evaluate(float x) {
return amplitude * (float) Math.sin(2 * Math.PI * x / waveLength + phaseDifference);
}
}
SineTerm , evaluate(x) ( ). . .
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