Reaction-Diffusion

Grows moving patterns steered by the image. Use the Calm / Fill Pad to move between waves, spots, and winding stripes.

Parameter	Control	Range	Notes
Look	Selector	Pattern, Picture	Pattern shows a black-and-white pattern with the image’s transparency. Picture shows the image through the pattern. Changing the look restarts it. Cannot be modulated.
Size	Selector	Large, Small	Small produces finer shapes and costs more to render. Changing size restarts the pattern. Cannot be modulated.
Calm / Fill	Pad	0 to 1 each	Calm runs left to right from restless waves to still shapes. Fill runs bottom to top from scattered spots to packed stripes and holes. The name below the Pad follows its current position, including modulation.
Follow	Trough	0 to 1	How strongly the image steers the pattern. Dark areas grow spots; bright areas grow stripes or holes.
Motion	Trough	0 to 2	How strongly movement in the image plants new pattern.
Speed	Trough	0 to 2	0 freezes the pattern.
Sharpness	Trough	0 to 1	Soft glowing edges at 0; crisp edges at 1.
Reset	Button and Lamp		Restarts from bright areas of the current image and scattered seeds. See Reset with modulation.

Pad regions

Region	Position	Pattern
Waves	Left edge	Moving fronts.
Spots	Bottom, left of center	Separate round dots.
Worms	Bottom, right side	Short winding lines.
Mazes	Middle and right	Long winding stripes.
Holes	Top, left of center	A packed field with round holes.

The pattern changes gradually across the Pad. Sparse and spotty regions keep planting new spots rather than settling completely.

To color the pattern, set Look to Pattern and place a Palette Map after Reaction-Diffusion.

Large runs at a quarter of the output resolution; Small runs at half. Small with Speed at 2 is the most expensive setting.

Perfect loop does not reset the pattern at the join. Use Video crossfade to blend the end into the start.