Galaxy Spiral
X-ray · layers
Parameters
How this effect works
This runs on the GPU. A single fragment shader is executed once for every pixel, in parallel, and returns a colour. For each pixel it converts its position to polar coordinates — a radius r from the centre and an angle a. A spiral is just a rule that ties the two together: a logarithmic spiral is where the angle drifts by the logarithm of the radius, which is exactly the shape real galaxy arms take.
The arms come from cos(arms · (a − log r + time)) — the time term slowly winds the whole pattern. Turn the Arms layer off and only the star field and core remain, which shows how much structure that one line carries. Stars scatters a hashed twinkle across the field, brighter where the arms pass; Core adds the hot central bulge. This is the shader-tier promise: a galaxy you can take apart — every slider is one uniform, and the Full-code tab is the real GLSL.