Homework Review

Today’s Groups

Today’s Learning Objectives


blue square

Consider the code you would write to draw a colored square. Your code would require several values: horizontal position, vertical position, width, height, the RGB values.

Where do those values come from?

Hard CodedYou want specific control of the value.
ParametersYou want to be able to control the value from a larger context.
random()You want random variation.
noise(x)You want controlled variation.

Often you use these in combination: width = 100 + random(-10, 10);

Using random() is a good way to add variation to a value. The noise(x) can often offer variation with greater control and consistency.



Benefits of Noise

Noise is Coherent

The noise(x) function returns values sampled from Perlin Noise. Perlin Noise provides random values that are aesthetically arranged (band limited and visually isotropic) in space. These values are a useful basis for many applications that require natural-feeling variation.

Noise is Repeatable

Repeated variation is easy with noise(x): every time you call noise(x) with a particular argument, you get the same value back. This is often very useful. For example, in an animation you often need variation to be consistent from frame to frame.

Noise is Controllable

By controlling what you pass to noise(x), you can control the frequency of the random values returned. This can be used to control how quickly values vary in space and time. Like random() values, you can scale and shift the values from noise(x) to the range you need. You can also adjust the character of noise(x) using noiseDetail().

1D Noise

Activity: Building 1D Noise

2D + 3D Noise

noise(x) noise_1d

noise(x, y) noise_2d

noise(x, y, z) noise_3d

Qualities of Noise

Working with Noise

Calling the Noise Function

When you call noise(x) you have to pass in an x value. This x value is the location in the Perlin Noise of the value to return. Choose x based on how you want the value to vary. You can pass in frameCount or millis() to get values that change over time. noise() actually takes up to three parameters: noise(x,y,z) allowing you to receive values arranged in three dimensions (see below).

Controlling the Frequency

You can control how quickly returned values will vary over time and space by scaling the value you pass in for x.

n = noise(frameCount); // get a value that changes over time
n = noise(frameCount * .1); // get a value that changes over time slowly
n = noise(frameCount * 10); // get a value that changes over time quickly

Controlling the Amplitude and Range

The noise(x) function returns values in the range of 0 to 1. Use multiplication and addition to shift this range to the range you need.

n = noise(frameCount) * 10 + 10; // values between 10 and 20;

You could also use map():

n = noise(frameCount); // 0 -> 1
n = map(n, 0, 1, 10, 20);  // map to 10 -> 20

Controlling the Detail

The noiseDetail() function allows you to control the “roughness” or “detail” of the noise returned. See: p5 reference

Controlling the Seed

By default, every time you restart your sketch the noise pattern will be different. The noiseSeed() allows you to manually set the noise pattern seed. See: p5 reference

Study Examples



Noise Applications


Tron Ken Perlin on Procedural Textures

Procedural Textures

Fireball clicktorelease.com: Fireball Wood Shiny Dynamics: Blender Wood Marble Modo: Marble

Procedural Shapes

Clouds Clouds

Terrain Displacement Terrain

Elevated 4K!


OpenCL Perlin Particles from Eddie Lee on Vimeo.

Open CL Perlin Particles


Keep Sketching! This week, focus on using the noise() function. Use noise() in a variety of ways. Use 1D, 2D, and 3D noise. Try using high, mid, and low frequency noise. Try using noise to control different things: position, size, color, rotation, etc. Think about tile graphics, random(), and parameters while you work. Consider combining these concepts with noise().

Special Assignment

Don’t forget to sign up for orientations for the Laser Cutter and 3D printer.


Make a program that generates treasure maps.

Your maps should:

Things to consider:

When posting your map:

Miscellaneous Links