Power-User Systems
Data Grid
ProA virtualised grid over thousands of rows: resizable columns, multi-key sorting, range selection and keyboard navigation. Header and body share one scroller so they can never desync, selection is keyed by row id so it survives a re-sort, and focus stays on the viewport so a recycled row can never take the arrow keys down with it. Give it a parent with a bounded height — like every windowing implementation, in an auto-height parent it quietly stops windowing and renders every row.
Install
Props
What It Demonstrates
- Skeleton / Shimmer
- A placeholder with a moving sheen shown while content loads.
- Layout thrashing
- Animating properties like width, height, top, or left that force the browser to recalculate layout every frame, causing jank.
- Frame rate (FPS)
- Frames drawn per second. 60fps is the baseline for smooth motion; 120fps on newer displays.
- Spatial consistency
- Animating so an element keeps its identity and position across states, so users never lose track of where things went.
- Frequency of use
- The more often a user sees an animation, the shorter and subtler it should be.
Related Components
MasonryPro
A Pinterest-style grid where every item drops into the shortest column, packed by measurement rather than by a shared row baseline.
Timeline ScrubberPro
Drag the head, snap it to markers, zoom into the track and let the viewport follow playback. One derived number — pixels per second — places the ticks, the pips, the head, the drag target and the follow scroll, so nothing on screen can disagree about where a time actually is.
Physics Engine
A from-scratch 2D rigid-body physics lab. Fixed-timestep impulse solver, drag-to-throw bodies, force and velocity overlays, and a live energy readout on a blueprint grid.
Black Hole
A real-time Schwarzschild black hole raytraced per-pixel in a WebGL2 shader. Null geodesics bend a lensed accretion disk over the event horizon, with Doppler beaming, gravitational redshift, a photon ring, and a lensed starfield, all under a cinematic orbit.
Approval Flow
A step-by-step approval checklist for agent permissions. Radio and checkbox groups, an "Other…" escape hatch that grows a field in place, and per-step validation that blocks the commit. Answering a step sends the chosen option flying into a running record of what you have already decided, so the screen accumulates a decision trail instead of replacing itself.
Diff Review
A review surface for a patch an agent has proposed. Accept or reject each hunk, fold long runs of unchanged lines away, and flip between unified and split. Switching views does not redraw the diff: every line is a shared element that flies from the stream into its column and back, so you never lose the line you were reading.