Lock Slider Wave

A glowing curve traces two sine waves simultaneously. Tune four sliders until your curve locks onto the target. When they align, the screen erupts in a cascade of light.

Lock Slider Wave gives you a curve and asks you to recreate it.

The curve is a Lissajous figure — a shape drawn by a single point whose horizontal position follows one sine wave and whose vertical position follows another, simultaneously. When the two frequencies are in a simple ratio, the path closes into a loop. When they are in a ratio of one to one and ninety degrees out of phase, the loop is a perfect circle. When the ratio is two to one, it becomes a figure-eight. When it is three to two, it becomes a three-lobed form that looks like a clover or a planetary orbit. When it is five to four, the path winds into a dense interlocking star that takes several seconds just to trace.

The gold curve on screen is your target. A bright dot races along it continuously, leaving a comet trail that fades behind it. Your curve is in electric blue, its own dot racing at the same speed. Four sliders control the parameters that define both curves: the x-axis frequency, the y-axis frequency, the phase difference between them, and the amplitude ratio. As you move any slider, your blue curve reshapes instantly — gaining lobes, losing them, stretching, rotating, collapsing and reopening as the mathematics changes beneath it.

The Lock bar at the top measures how closely your curve matches the target, computed by sampling three hundred points on each curve and measuring average distance. Getting to seventy percent is straightforward. Getting to ninety requires understanding what each slider actually does — how changing the frequency ratio from two to one to three to two adds a lobe, how sweeping the phase from zero to ninety degrees rotates and opens the figure, how the amplitude ratio stretches or compresses without changing the curve's fundamental topology.

When the match crosses ninety-two percent, the two curves merge. The screen holds for a fraction of a second — both curves burning white — and then a hundred particles erupt from every point on the curve simultaneously, flying outward along the curve's normals in gold and yellow and white. The win sound is the actual musical interval corresponding to the frequency ratio you solved: a three-to-two Lissajous sounds a perfect fifth, a two-to-one sounds an octave, a four-to-three sounds a perfect fourth. The mathematics of the curve and the mathematics of music are the same mathematics. The game makes that audible.

Lissajous figures appear on oscilloscopes when musicians tune instruments. They describe the orbital resonances of Jupiter's moons. They appear in antenna radiation patterns, quantum mechanical orbital shapes, and the path of a pendulum suspended from another pendulum. Lock Slider Wave makes them tactile — something you feel through your fingertips as you drag sliders and watch a curve reshape itself in real time.

At low scores the frequency sliders are locked to the correct values. Only phase needs tuning. The phase sweep alone — watching a figure-eight rotate and flex as the slider moves — is worth the price of admission. All four sliders unlock as your score climbs.

No ads. No prior knowledge of trigonometry required. The curves are self-explanatory. The satisfaction of locking is immediate.

Just the slider, the curve, and the moment everything aligns.