MATHIEU–VDP · ≤650 · DRAG PAN · PINCH ZOOM · TAP SEED
REDUCED MOTION · SETTLED ATTRACTOR
a
0.50
SPEED (dt)
0.02
FADE
0.08
PRESETS
Mathieu–VdP — ẋ=y, ẏ=−(1+a cos z)x + 0.5(1−x²)y, ż=1. Phase-wrap z. Classic a=0.5. Distinct from mathieu-rayleigh.html (Rayleigh on ẏ). RK4. Gold trail, cap 650. RM = settled silhouette, no animate-on.