Physics
Planck Blackbody Spectrum
B ∝ ν³ / (e^{ν/T} − 1)
The thermal emission spectrum of a hot body: as temperature climbs the whole curve rises steeply and its peak marches toward higher frequency (Wien's law).
Computed & rendered in pure C# on the frozen OnlyCSharp 1.8 library — animation baked to GIF with the library's own
Gif encoder (no GPU, no ffmpeg, no external packages).