Clock Wipe — effect skill for transitions

For AI agents: find the right skill in one call — curl -s "https://skills.varg.ai/api/search?q=<what the person wants>" returns the matching how-to page and the best skills with install commands, as markdown (Russian works too). Full index: https://skills.varg.ai/llms.txt. Every page has a markdown twin: add .md to its path. Before generating anything, show the person the options on the how-to page.

A hand sweeps around the centre like a clock, replacing A with B.

What it does

Built on Radial Transitions by HeyGen (HyperFrames), Apache-2.0. The write-up and recipes below are varg's.

A radial edge rotates 360° from 12 o'clock; Windmill uses several blades.

When: Countdowns, time-based stories, playful retro edits.

Watch out: Modern minimalist brands; it is a strongly retro look.

Timing: 0.5–1.0 s (CapCut Clock wipe 0.47 s)

Also called: Clock wipe, radial wipe, Windmill, angular wipe

In FFmpeg

Same size/fps/pixel format on both inputs (see the Normalize card). offset = duration(A) - T = 5.0 - 0.8 = 4.2.

ffmpeg -i a.mp4 -i b.mp4 -filter_complex \
"[0:v]fps=30,settb=AVTB,format=yuv420p[a];[1:v]fps=30,settb=AVTB,format=yuv420p[b];\
[a][b]xfade=transition=radial:duration=0.8:offset=4.2[v];\
[0:a][1:a]acrossfade=d=0.8[au]" \
  -map "[v]" -map "[au]" -c:v libx264 -crf 18 -c:a aac out.mp4

In HyperFrames

Block transitions-radial; CSS clock wipe: a 9-point polygon stepped through 4 quadrants (see the HyperFrames mechanical transitions reference).

In Remotion

import {TransitionSeries, linearTiming, springTiming} from '@remotion/transitions';
import {clockWipe} from '@remotion/transitions/clock-wipe';

<TransitionSeries>
  <TransitionSeries.Sequence durationInFrames={90}><ShotA /></TransitionSeries.Sequence>
  <TransitionSeries.Transition presentation={clockWipe({width: 1920, height: 1080})} timing={linearTiming({durationInFrames: 24})} />
  <TransitionSeries.Sequence durationInFrames={90}><ShotB /></TransitionSeries.Sequence>
</TransitionSeries>

Total = 90 + 90 - 24 frames: the transition overlaps the two shots. clockWipe() requires width and height.

In CapCut

Transitions tab → Basic / Wipe → Clock wipe, Windmill. Desktop: drag the tile onto the cut between two clips and set Duration in the right panel ("Apply to all" reuses it on every cut). Mobile: tap the small white square between clips, pick the transition, drag the duration slider, tap ✓. Tab labels and placement change between versions and regions.

Ready-made components

Where this comes from

Use when

Not for

Install

Example output

https://s3.varg.ai/how-to/previews/39c62ab3e8fa/take-clock-wipe.mp4 — radial between two shots, with the timeline strip of the edit. Footage: WING IT! (2023), Blender Studio | studio.blender.org, CC BY 4.0; Coffee Run (2020), Blender Studio | studio.blender.org, CC BY 4.0. (credit: Rendered by varg · WING IT! (2023) + Coffee Run (2020))

More transitions skills

Run the generation on varg

varg is one API key for the models these skills drive — Seedance 2.5, Kling 4, Veo 3.1, Wan 3, Nano Banana 2.1, GPT Image 2.5, ElevenLabs v4 and 200+ more — billed in credits, with a cost estimate before anything runs.