Mode
Parameters
Animation
Image overlay
Math
Golden ratio (phi)
1.6180339887498948482…
Golden angle
137.5077640500378546… degrees
Fibonacci sequence
What this is
The golden ratio is the proportion where the whole is to the larger part as the larger part is to the smaller, about 1.618. Five modes draw what follows from it: a Fibonacci spiral, a phyllotaxis seed head, a Penrose tiling, Voronoi cells grown on the golden angle, and a golden rectangle cut down square by square. Load a photo and the same proportions become composition grids you can lay over it.
How to use it
- Pick a mode, then set its depth or count.
- Tap the canvas to move the center, and pinch or scroll to zoom.
- Add an image to lay a composition grid over it, then save a PNG.
Read the guide
Words: golden ratio · aspect ratio · canvas
Common questions
How do I zoom?
With a mouse or trackpad, scroll over the canvas. Each step zooms by a tenth, towards the pointer. On a touch screen, pinch with two fingers. The zoom follows the point between your fingers, and moving both fingers together moves the view.
How do I move the view?
With two fingers on a touch screen. A mouse cannot drag the view; zoom towards the part you want with the wheel instead, or tap to move the centre of the drawing. Reset zooms back to the start.
Does it work on a phone or tablet?
Yes. Every mode, overlay and export is there. On a phone, or on any touch screen or window under 900 pixels wide when the page opens, the sliders stop lower: 2500 points, 6 subdivisions and 100 seeds. Voronoi cells are worked out in coarser patches, and the canvas is drawn at no more than twice the screen's pixels.
What background does my PNG have?
The frame's own near-black, painted into every pixel, so no part of the PNG is see-through. With a photo loaded, the photo covers it, except where you have zoomed out past the photo's edges.
On the blog: How to analyze composition, lighting, colour and materials