Mandelbrot explorer

Every pixel of this fractal is computed on the server and sent as inline SVG: neighbouring pixels of the same color are merged into horizontal lines, and all lines of one color share a single path. To show something as early as possible, the page first streams a blurry preview at 1/8 of the resolution. Then an async function* component computes the image in strips of 32 rows and yields each strip as soon as it is ready, so the sharp picture builds up from top to bottom while the rest is still being computed.

Click into the image to zoom in by a factor of four, or drag a box to zoom into that area. A small script turns your selection into new coordinates and reloads the page, which keeps your scroll position. Everything else happens on the server.