Using the timeline

Below each graph window is a timeline. Toggle its visibility in Application Menu → View → Timeline.

The graph's toolbar controls a few aspects of it:

• Playback settings — soundtrack, BPM, audio input.
• Timeline format — raster between bars, seconds, or frames.
• Loop playback — show the loop (work-area) handles.
• Dope / Curve — switch between the two primary editing modes.

Controlling playback time

Scrub time by dragging in the lower shaded section of the timeline. (The upper area is for selecting keyframes and time clips — see Selecting timeline elements.)

Playback shortcuts:

• Space — toggle playback.
• Home — jump to start.
• L — play forward; press again to speed up.
• J — play backward; press again to speed up.
• K — stop.
• . / , — jump to next / previous keyframe.
• Shift + ← / Shift + → — step 30 ms.

Hold Shift while scrubbing to snap to the bar raster and other timeline elements.

Snapping and the time raster

In the background the time raster shows the current grid. Switch between:

• Bars — uses the project's BPM.
• Seconds.
• F30 and F60 frames.

Dragging timeline elements snaps to the bar raster by default. Zoom in for finer subdivisions (beats, ticks); zoom out for coarser ones (measures, phrases). Hold Shift to disable snapping. Raster density is configurable in Settings.

Selecting timeline elements

Keyframes and time clips can be selected in a few ways. The selection drives both the selection range indicator (above the timeline) and the keyset indicators (the strip just below the ruler).

Keyset indicators (the strip below the ruler)

Every visible keyframe — or cluster of nearby keyframes — is represented by a small dot in the strip directly below the ruler:

• Unselected — hollow dot.
• Partially selected — filled dot with a notch (some keys in that cluster are selected).
• Fully selected — filled dot.

Interactions:

• Click a dot — select the keys that dot represents, replacing the current selection.
• Drag a dot — move those keys through time without touching the broader selection.
• Click on the background (no dot under the cursor) — clear the keyframe selection.
• Drag on the background — fence-select. While you drag, the dots under the fence preview as selected. Hold Shift to add to the current selection, Ctrl to remove from it.

Clusters automatically merge when keys are within ~2 px on screen, so zooming in exposes individual dots and zooming out combines them.

The selection range indicator

Inside the ruler there's a thin horizontal bar — the selection range indicator (SRI) — that spans the current selection:

• When keyframes are selected, the bar covers their time range (plus any selected clips).
• When nothing is selected, the bar dims to 30 % opacity and spans the extent of all visible keyframes, letting you grab everything at once without pre-selecting.

The bar has three hit regions, each lighting up independently when hovered:

• Start handle (left edge) — stretch from the right.
• End handle (right edge) — stretch from the left.
• Middle line — translate the whole selection.

Stretching. Drag either edge handle to scale the selected keyframes and clip endpoints proportionally around the opposite fixed boundary.

Translating. Drag the middle to shift everything. The translation snaps when the selection's start or end aligns with a snap target (raster, current time, clip boundary, etc.) — whichever gets a closer match wins. Hold Shift to bypass snapping.

If nothing is selected, an SRI drag auto-selects every visible keyframe first, so you can simply grab the bar and stretch all keys of the visible parameters together.

TimeWarp handles

For retiming a section of the selection non-uniformly, the SRI supports TimeWarp handles — small filled circles placed on the bar.

• Alt + Click on the bar inserts a handle at the cursor.
• Alt + Click on an existing handle removes it.
• Drag a handle (with or without Alt) to retime keys and clip endpoints in the two adjacent segments. The previous handle (or the SRI start) and the next handle (or the SRI end) stay pinned; everything between them is remapped piecewise-linearly around the moving handle.
• With handles present, dragging the SRI start or end retimes only the outermost segment instead of stretching the whole selection.
• Middle-translating the SRI shifts the handles along with the keys, so they stay visually attached.

Handles are cleared automatically when you replace the keyframe selection (clicking a different keyset indicator, fence-replacing, or deselecting everything). Adding to or removing from the existing selection leaves them in place. Handles outside the current selection range are hidden.

Handle drags are undoable — Ctrl + Z restores both the keyframes and the handle positions. Inserting and removing handles themselves is not part of the undo history.

While Alt is held, hovering the bar previews an outlined circle at the cursor — solid outline means "insert here", centered on an existing handle means "remove this one".

Scrub, no-drag, and the legacy range

Directly under the ruler you may also see the older time-selection range (a translucent band with handles at the bottom of the canvas) while holding Alt over the dope sheet. It has the same stretching behavior as the SRI and is kept for muscle-memory compatibility — the SRI is the recommended workflow.

Working with the Dope Sheet

The dope sheet displays the keyframes of the currently selected operators.

Adding and editing keyframes

To animate a parameter, click its input in the Parameter Window while holding Alt to insert the first keyframe:

Once animated, you can:

1. Insert new keyframes by modifying the parameter value.
2. Toggle keyframes via the keyframe indicator in the parameter window.
3. Adjust interpolation via the context menu.
4. Adjust a keyframe's value by selecting it and editing in the parameter window.
5. Insert keyframes on a curve by Alt-clicking the animation curve directly.

To remove an animation either delete all its keyframes or reset the parameter by clicking its name in the parameter window.

Displaying keyframes

By default, only the keyframes of selected operators appear in the timeline. Enable Keep animated parameters visible in the toolbar to keep parameters pinned even when you select other operators:

If too many parameters stack up, press Ctrl + Shift + K twice to clear the list.

Interpolation and tangents

The keyframe context menu switches between interpolation modes. For fine control of tangents, flip the mode toggle from Dope Sheet to Curve and edit the curve directly.

Inserting animation increments

Press Shift + C to insert a keyframe whose value is incremented by 1 relative to the previous one. This is useful for tapping step markers while a soundtrack plays:

1. Add a soundtrack to your project.
2. Press Home to jump to the start.
3. Create a [Value] operator and animate it. Set its interpolation to Constant.
4. Press Space to play.
5. Press Shift + C on every beat you want to mark. Keyframes with values 1, 2, 3, … appear at those times.
6. Feed the animated value into [HasValueChanged] + [TriggerAnim] (or similar) to drive events.

To recompute the keyframe values after inserting or deleting keys:

1. Shift + Click the keyframe row to select all keyframes.
2. Run Recount values from the context menu.

Working with time clips

Some operators — notably [TimeClip] and [VideoClip] — output time clips. They're evaluated only while the current playback time falls within their clip time; outside that window they're skipped, as if disabled.

If a composition contains any time clips, the timeline shows a Time Clip Area above the dope sheet. Combine clips with a [Group] to build a scene timeline:

The active clip is highlighted during playback.

Time clips need to be connected

[!NOTE] Clips not connected to a consumer never render unless they're pinned to the output window. TiXL fades unconnected clips and shows a "Not Connected?" warning on their tooltip:

Editing time clips

Drag one or more clips with the left mouse button. They snap to:

• The timeline raster (in Bars mode).
• Other time clips.
• The current playback time.
• Other keyframes.
• The loop range (when active).

Hold Shift to disable snapping. Rename a clip by pressing Return.

Time clip layers

Drag clips vertically to distribute them across layers. Layers do not affect rendering order — connection order in the group does. TiXL distributes overlapping clips into separate layers automatically; Ctrl + Shift while dragging vertically adjusts only the layer index.

Time remapping

Time remapping lets a clip scale or offset the source time it exposes to its sub-graph — similar to [SetCommandTime], but local to the clip.

In the example above, the second clip plays its contents at 500 % speed. The red bar at the bottom of the clip indicates the remap.

Selecting a single clip shows two curves visualizing the mapping from clip time to source time:

Ways to edit the remap:

1. Drag a clip's start or end while holding Alt.
2. Slip-drag the source region by dragging inside the clip with Alt + Ctrl.
3. Select clips and choose Edit Clip Times from the context menu.
4. Clear Time Stretch from the same menu resets the mapping.

[!NOTE] Remapped time interacts with keyframe editing in sometimes-surprising ways. Consider whether the remap is actually necessary before committing to it.

Splitting clips

Select one or more clips and run Cut at Time from the context menu. Each clip splits at the current playback time; the new clip is renamed and reconnected to the same target group.

Nesting timing

If an operator symbol has an output flagged as time clip, instances of that operator also appear in the time clip area. Unlike [TimeClip], nested time-clip operators do not link their source time to the clip time — moving such an operator from t=0 to t=1 bar leaves its source time at 0.

Editing videos

The clip workflow doubles as a lightweight video editor for [VideoClip]s. Seeking inside heavily-compressed sources is slow; if you plan to scrub a video, re-encode it first with an all-intra preset:

ffmpeg -i input.mp4 -g 1 -c:v libx264 -preset veryfast -crf 18 output.mp4

Clip Timing Editor

Open the Clip Timing Editor to set precise times for one or more selected clips:

When a selection contains multiple values, the editor shows NaN for the mismatched field — type a number to set it across all selected clips at once.