Documentation
Physics
Some particles move in a random vector field, somehow following Newton's second law of dynamics.
Particle settings
After the particle speed is updated from the vector(s), a slow-down coefficient is applied to the speed.
The
particle speed slider lets you choose this coefficient between 0 and 1 (1 means not slowed-down).
Vector field settings
The vector field is generated from Perlin noise, but there are two methods here.
The first one (
Basic) uses 3D Perlin noise to generate random vector angles in 2D in a "continuous way". The third dimension is used as time to get the angles to change.
The second method (
Moving torus in 3D) is similar, but it uses a torus that moves randomly through 3D Perlin Noise to take the vector angles values. That way there are no problems on the borders.
A new problem that appears is that the generation is unbalanced, some areas are "contracted" in 3D space.
There is a clean way to avoid that by using 4D noise, but it doesn't seem easy to get in javascript.
When
Space size is increased, the noise is used on a larger area, so that more discontinuity with space appear.
When
Vector noise is increased, some random values of higher intensity are added to the field before it affects each particle (different valeus for each particle).
Vector field magnitude controls the norm (i.e. intensity) of the vectors in the vector field.
Vector change rate controls the speed at which we evolve using the third dimension of the Perlin Noise.
Field bias
Something to add constant values to the vector field.
Drawing style
Color gradient
The color gradients use functions of the form value(t) = a + b*sin(c + w*t) to compute the red-green-blue components of the colors.
The parameters a,b,c and w can be different for each component, and even each particle (c changes with
particle color offset).
All the sliders in this section are about defining these parameters.
Color noise settings
Some perlin noise (noise(c + w*t)) can be added to each color component.
Synchronized color noise adds the same noise to all components.
The previous parameter w is controlled with
noise "frequency".
The parameters a,b,c and w can be different for each component, and even each particle (c changes with
particle color offset).
All the sliders in this section are about defining these parameters.
Rectangle mode
This mode is the same as the default one, excepted that the particles are drawn with rectangles :
the particles are constrained to move only up down left or right, and a new rectangle is drawn from the previous one using the speed as width or
height (depending on the direction).
Custom color gradient
This panel allows you to paint the canvas with your own picture (press pause to have only the picture on the canvas).
Then you can define a color gradient from there by picking points from an ellipse or just randomly to define the colors.
There's a button to optimize (order) the colors.
Tricks
Resize your window before reloading the page (Reset button) to use smaller resolutions.
