Cells and exposure
How drawings sit on the timeline as cell strips: adding and duplicating cells, stretching a hold, trimming an exposure and clearing frames.
Raster and Vector layers do not store one drawing per frame. They store a library of cells, and each frame simply points at one of them. A cell stays on screen until the next cell starts, so a drawing exposed on frame 5 with nothing after it until frame 9 is held for four frames. Edit that cell once and every frame using it updates.
On the timeline, a Raster or Vector layer gets an extra band under its keyframe row: the cell strip. Each exposure is drawn as a thumbnail block that runs the length of its hold, so the timing of a hand-drawn scene is readable at a glance.
Sizing the strip
Right-click the layer row and pick Thumbnail Size: None, Small, Medium or Large. Medium is the default; None collapses the strip and leaves only the keyframe row. The setting is remembered between sessions.
Rest the cursor on a raster cell for about half a second and a large preview of that drawing floats next to the pointer, so you can check a cell without moving the playhead. The wait is the Cell Preview Delay in Preferences: 0 to 2 seconds, 0.40 s by default, and 0 turns the preview off.
Adding, duplicating and removing cells
When a Raster or Vector layer is the selected layer, three buttons appear in the timeline toolbar: Add Cell, Duplicate Cell and Remove Cell. Duplicate and Remove are disabled while no cell is visible on the current frame.
| Button | On a Raster layer | On a Vector layer |
|---|---|---|
| Add Cell | On a cleared frame, brings the frame back and starts a cell there. On a frame that already starts a cell, makes a new blank cell on the next frame. On a held frame, starts a new cell where you are. | On a frame that already holds its own drawing, makes a new empty cell on the next frame. On a held or blank frame, makes the new cell right there. |
| Duplicate Cell | Copies the visible drawing onto the next frame as a new cell. | Copies the visible drawing onto the next frame under a new cell id, so the copy is independent: repainting it leaves the original alone. |
| Remove Cell | On the cell's own frame, deletes the exposure. On a held frame, blanks the frames up to the next cell. | Clears the cell's drawing and leaves a blank frame in its place, so the previous cell does not bleed forward. |
Stretching and moving a hold
A raster exposure can be re-timed straight on the keyframe row. Grab the right end of the block and drag: dragging right lengthens the hold and pushes every later cell forward by the same amount, dragging back shortens it and leaves blank frames behind. Pull it back to where it started and the later cells return to exactly where they were.
Grab the left end instead and you move where the cell begins. Dragging left grows the cell into the empty space before it, eating into the previous cell's tail if it has to; dragging right shrinks it and blanks the frames it gave up. The edges are live within about five pixels of the block's end, and the cursor changes to a horizontal resize arrow when you are on one.
Trimming an exposure
Each run of exposed frames on the cell strip carries two small square handles: one at the top left of the run, one at the bottom right. A modifier picks what the drag does to everything around it. Raster Cells and Vector Cells layers behave identically here:
| Drag | Ripple: the cell resizes and the cells after it are pushed along |
| Shiftdrag | Isolate: only this cell changes, the blank gap beside it opens or closes and the neighbours stay put |
| Altdrag | Trim, rolling the seam: as this cell shrinks the neighbour grows into it, and nothing beyond the neighbour moves |
Growing a cell leftwards moves its key, so the cell itself extends rather than the previous cell spilling into the gap. Without that, exposing an earlier frame would only show whichever cell is already held from further left.
Blank frames
A blank frame is a frame where the layer is explicitly not drawn, different from a frame that has never had a cell, because a blank frame stops the previous drawing holding forward through it. Blank frames render dark with a diagonal hatch on the keyframe row.
Right-click a frame on the layer row and choose Clear Frame to blank that one frame. The held drawing carries on as normal from the next frame. Clearing one frame never wipes the rest of the hold. The item is offered only on a frame that has no keyframe and is not already blank.
To blank a whole stretch, double-click an empty part of the row first: that selects the entire run of unexposed frames between the keys on either side, and the menu then offers Clear Frames for the whole run.
On a frame that is already blank, the same menu offers Add Blank Frame, which brings the frame back.
Dragging a cell in from the Cells panel
The Cells panel lists every cell the selected layer owns. Drag one out of the panel and onto a frame in that layer's timeline row to expose it there. This is how you reuse a drawing you have already made rather than redrawing it.
- Select the Raster or Vector layer so it is the primary selection.
- Open Window ▸ Cells if the panel is not already up.
- Drag a cell thumbnail from the panel onto the timeline row.
- Drop it on the frame you want. The playhead follows the drop.
While you drag, the target row is outlined and the frame under the cursor tints green when the drop is allowed and red when it is not. A frame that already starts a cell always refuses the drop, so an existing exposure can never be silently overwritten. Only the layer the cell belongs to accepts it.
Extending a whole stretch of timing
The +1, +2, +3 and +4 buttons in the timeline toolbar extend the current pose or cell by that many frames, rippling everything after it forward on every selected layer, and growing the scene length if it needs to. It is the quickest way to slow a section down without dragging each key.