A composition is a timeline of scene objects for cuts and cutscenes. This first step brings the model and the pure evaluation behind it. The tab and placing it in a scene follow in the next steps. - CompositionAsset holds objects, tracks, items and clips. Each item owns exactly one object with overrides and container edits. - The composition is a third object holder next to scene and container. Delete cascade, undo, usages and references work with it. - Duplicating gives the copy new object ids and moves the item ids along with them. - compositionAt() tells which items live at a frame. The top track is drawn in front. - A clip acts on the item of its own track that it overlaps. After its end it holds the last value until the item ends. The animation's play mode is ignored, a clip is one pass. - Clip targets are found by template path, else by name path, like the runtime's animation system. - The root sprite of an item plays its video driven at offset plus time. Children follow unless they are already driven by hand. - fittedLength() gives the video or clip length minus the offset, or 3 s without media. - fps (60) and loop live in their own properties file. Keeping them in PropertySchema would close an import cycle. - The type is listed under Visuals with its own icon. It is not placeable yet. Tests: the gate passed with 300 files and 4625 tests. That is 25 new tests in tests/core/composition.test.ts and 2 icon checks that run for every icon. Four counter-checks (track order, overlap rule, child videos, ids on duplicate) each turned exactly their test red. e2e 04 passed with 67 checks and now counts 33 asset types. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
696 B
696 B