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    Simple Noise node

    The Simple Noise node generates a pseudo-random value, also known as value noise, for each UV coordinate in the input UV.

    Ports

    Name Direction Type Binding Description
    UV Input Vector 2 UV The UV coordinates to input. For example UV coordinates, refer to UV Nodes.
    Scale Input Float None How much to scale the size of the output. A higher value zooms out so there are more noise values in the same space. The default is 500.
    Out Output Float None The simple noise. The range of each value is between 0 and 1.

    Generated Code Example

    The following example code represents one possible outcome of this node.

    inline float unity_noise_randomValue (float2 uv)
    {
        return frac(sin(dot(uv, float2(12.9898, 78.233)))*43758.5453);
    }
    
    inline float unity_noise_interpolate (float a, float b, float t)
    {
        return (1.0-t)*a + (t*b);
    }
    
    inline float unity_valueNoise (float2 uv)
    {
        float2 i = floor(uv);
        float2 f = frac(uv);
        f = f * f * (3.0 - 2.0 * f);
    
        uv = abs(frac(uv) - 0.5);
        float2 c0 = i + float2(0.0, 0.0);
        float2 c1 = i + float2(1.0, 0.0);
        float2 c2 = i + float2(0.0, 1.0);
        float2 c3 = i + float2(1.0, 1.0);
        float r0 = unity_noise_randomValue(c0);
        float r1 = unity_noise_randomValue(c1);
        float r2 = unity_noise_randomValue(c2);
        float r3 = unity_noise_randomValue(c3);
    
        float bottomOfGrid = unity_noise_interpolate(r0, r1, f.x);
        float topOfGrid = unity_noise_interpolate(r2, r3, f.x);
        float t = unity_noise_interpolate(bottomOfGrid, topOfGrid, f.y);
        return t;
    }
    
    void Unity_SimpleNoise_float(float2 UV, float Scale, out float Out)
    {
        float t = 0.0;
    
        float freq = pow(2.0, float(0));
        float amp = pow(0.5, float(3-0));
        t += unity_valueNoise(float2(UV.x*Scale/freq, UV.y*Scale/freq))*amp;
    
        freq = pow(2.0, float(1));
        amp = pow(0.5, float(3-1));
        t += unity_valueNoise(float2(UV.x*Scale/freq, UV.y*Scale/freq))*amp;
    
        freq = pow(2.0, float(2));
        amp = pow(0.5, float(3-2));
        t += unity_valueNoise(float2(UV.x*Scale/freq, UV.y*Scale/freq))*amp;
    
        Out = t;
    }
    
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