Auto-Sequencing & Duration Shorthand

For video, image, and audio clips, you can reduce timeline boilerplate with two shortcuts:

• duration — use instead of end. The library computes end = position + duration. You cannot specify both on the same clip.
• Omit position — the clip is placed immediately after the previous clip on its track. Video and image clips share the visual track; audio clips have their own track. The first clip defaults to position: 0.

// Before: manual position and end for every clip
await project.load([
  { type: "video", url: "./a.mp4", position: 0, end: 5 },
  { type: "video", url: "./b.mp4", position: 5, end: 10 },
  { type: "video", url: "./c.mp4", position: 10, end: 18, cutFrom: 3 },
]);
 
// After: auto-sequencing + duration shorthand
await project.load([
  { type: "video", url: "./a.mp4", duration: 5 },
  { type: "video", url: "./b.mp4", duration: 5 },
  { type: "video", url: "./c.mp4", duration: 8, cutFrom: 3 },
]);

Mixing explicit and implicit positioning

You can mix explicit position values with auto-sequenced clips freely. Clips with an explicit position are placed there; subsequent auto-sequenced clips follow from the last placed clip’s end:

await project.load([
  { type: "video", url: "./a.mp4", duration: 5 },        // position: 0, end: 5
  { type: "video", url: "./b.mp4", position: 10, end: 15 }, // explicit gap
  { type: "video", url: "./c.mp4", duration: 5 },        // position: 15, end: 20
]);

Text overlays require explicit timing

Text clips always need an explicit position (and end or duration) — they target specific visual moments and don’t participate in track sequencing.

Background music and subtitle clips have their own defaults (position: 0, end: project duration) and also don’t auto-sequence.