Grid Pulse
X-ray · layers
Parameters
How this effect works
The base grid is the cheapest thing on this page: one faint line per column and per row, redrawn each frame. The interesting part is the pulse. It is not an object moving through the scene — it's a number: the wave's current radius, growing steadily and starting over when it leaves the screen. Every grid intersection asks how far am I from that radius? and the answer feeds a bell curve — exp(-(distance/width)²) — that peaks exactly on the ring and dies off smoothly either side.
That bell value w is then spent on light: intersections near the ring get a bright cross of half-cell arms and an enlarged node dot, both with opacity scaled by w. Points far from the ring get w ≈ 0, so we skip them without drawing anything — the wave touches maybe a tenth of the grid at any moment, and that's the performance story: cost follows the ring, not the screen.