Arranging Effects in Time

Effects in a composition live in time: each effect occupies its own bar on the Timeline — with a start, an end, and a duration. While the time cursor is inside the bar, the effect is rendered on the fixtures; outside it, the effect simply doesn't exist. By arranging bars along the scale and layering them over one another, individual effects are assembled into a finished animation.

This article is about working with bars: how to move an effect, shorten it, position it at the exact second you need, and what happens at the boundaries of a composition. For the window itself and its panel, see Таймлайн; for adding effects, see Добавление эффекта в композицию.

What the effect bar shows

Open a composition by double-clicking it in the Composition window — its contents will appear in the Timeline window.

On the left are listed the layouts and the effects nested inside them; on the right, on the time scale, are the bars for these effects. To see a layout's effects, expand it using the triangle to the left of its name: a collapsed layout shows no bars.

An effect bar is a light gray rectangle on the layout's dark track. Its left edge is the moment the effect starts, its right edge is when it ends, and its width is its duration at the current scale of the timeline. A bar under the mouse cursor lightens slightly; a selected one lightens noticeably.

A few important points:

an effect works only within its own bar and switches on and off abruptly: the bar itself has no fade-in or fade-out — smooth transitions are made with opacity keyframes, see Ключевые кадры и параметры эффектов;
time inside an effect is counted from the left edge of the bar, so its whole animation travels together with the bar: move the effect 10 seconds later, and its motion starts 10 seconds later too;
a new effect added from the Effects window occupies the entire composition — from zero to its end. After that it is shortened and moved manually;
the checkbox to the left of the effect's name turns it off entirely, regardless of the bar's position: with the checkbox cleared, the effect plays nowhere and is excluded from export.

Selecting bars

Click a bar with the left mouse button — the effect is selected, and its parameters open in the Properties window.

Ctrl + click — add the effect to the selection. Shift + click works the same way, but Shift is already used for snapping while dragging, so Ctrl is more convenient for selecting.
Clicking an empty area of the timeline deselects all effects.
Selected bars move and are deleted together — as a single group.

Shifting an effect in time

Select a bar (or several bars).
Press the left mouse button on the bar's middle and, without releasing it, drag the mouse right or left. Dragging doesn't start immediately but after a small offset — a short click won't move the bar.
Release the button at the desired position. The image on the Mapping field and in the 3D View is recalculated instantly.

What happens:

the effect always lands on a frame boundary — it's impossible to land "between frames";
the bar's duration doesn't change, only its position does;
the effect doesn't go beyond the composition's bounds: at the zero mark and at the end of the composition the bar stops at the boundary and goes no further;
several selected bars move together, keeping the distances between them. But at the composition's boundaries each bar stops on its own, and their relative positions can shift — when moving a group, it's best not to push it right up against the edge;
the layout doesn't change while dragging along the scale. To move an effect to another layout, drag it by its name row in the left part of the window — see Moving Effects Between Layouts.

Changing duration

Move the cursor to the left or right edge of the bar: right at the edge the cursor changes into a resize arrow. Drag the edge — the bar stretches or shortens, while its other edge stays in place.

Edge	What changes
Right	The effect's end moment. The edge doesn't go past the end of the composition
Left	The effect's start moment. The effect's keyframes stay in their positions in time — only the reference point shifts, and the animation is "trimmed" from the front

Limitations:

an effect can't be made shorter than one frame — the bar stops at the minimum length;
only regular effects' edges can be dragged. An imported video's bar can't be dragged by its edges: its length is calculated automatically from the file's duration and the number of repeats, which is set in Properties;
stretching an effect doesn't stretch its animation: the keyframes stay where they were, and after the last keyframe the values simply stop changing.

Snapping bars to each other

During normal dragging, a bar moves freely. To join effects edge to edge, without a gap or overlap, hold Shift — snapping turns on. While the key is held, the edge of the bar being dragged sticks to:

the starts and ends of all other bars visible on the timeline (including in other layouts);
the start of the composition;
the current position of the time cursor.

The point being snapped to is shown by a vertical blue line. Snapping works both when moving the whole bar and when dragging either of its edges. Release Shift and the bar moves freely again.

A time-saving trick: place the time cursor at the moment you need — it's easier to aim at than an empty scale — and pull the edges of bars to it while holding Shift.

Exact start and end time

When you need not "by eye" but exactly at 00:00:12, right-click the bar and choose Set time. A small window opens with three fields in the format hours:minutes:seconds:milliseconds:

Field	Value
Start	The effect's start time
End	The effect's end time
Duration	Duration; changing this field moves the effect's end, the start stays in place

Values are applied immediately as you type, and the window closes with the Enter or Esc key. The same right-click menu has a Delete item — delete the selected effects.

Time cursor

The orange vertical line on the timeline is the time cursor: it shows which moment of the composition you're currently seeing on the Mapping field and in the 3D View.

Click the upper ruler with the time scale — the cursor moves to that point. Without releasing the button, you can drag it along the scale and "scrub" the animation manually; playback is paused while you do this.
Spacebar — play and pause, Home — go to the start of the composition, End — go to the end.
Ctrl + → and Ctrl + ← — step one frame forward and back, Ctrl + Shift + → and Ctrl + Shift + ← — ten frames at once. Frame-by-frame stepping is handy for checking whether an effect starts exactly where it's supposed to.

The current time and frame number are shown on the timeline's playback panel, with the composition's duration next to them.

Scale and scrolling the timeline

Bars a fraction of a second long can't be made out on a minute-scale timeline, so the scale can be changed on the fly:

mouse wheel over the scale — zoom time in and out. The scale changes relative to the pointer, so aim it at the section you want to examine;
dragging with the wheel held down (or the right button) — scrolling: horizontally scrolls time, vertically scrolls the list of layouts and effects. A short right-click still opens the context menu.

The timeline's scale only affects the view: it has no effect on the effects themselves or on export.

Overlapping effects in time

Within one layout, bars can overlap in time as much as needed. At a moment when several effects are playing at once, they're composited top to bottom: an effect higher in the layout's list is drawn over the ones below it, according to its blend mode and opacity. The order is changed by dragging the effect's row in the left part of the window, see Режимы смешивания.

This gives rise to two common techniques:

scene change — bars go edge to edge: one ends, the next begins. Easiest to set up with Shift snapping;
smooth transition — bars overlap, and the upper effect's opacity is animated with keyframes within the overlap zone.

To repeat an effect later in the composition without configuring it again, right-click the effect's row in the left part of the window and choose Duplicate: a copy appears in the same layout at the same point in time, after which you just need to drag it.

Composition boundaries

The length of the scale is the composition's duration. It's set in the composition's settings: right-click the composition → Set Duration, or click the duration value on the timeline panel. See Настройки композиций.

Things to keep in mind:

effects can't extend past the end of the composition: when dragging and stretching they stop against it;
if you set the composition to a shorter duration, effects that no longer fit are trimmed at the new boundary. Restoring the previous duration isn't enough — trimmed bars will have to be stretched again, so it's better to set the duration before arranging effects;
in a composition with Infinity enabled, time keeps running past the end of the scale. At that point only effects stretched all the way to the composition's end keep playing: the rest have already finished by then;
the cue file receives exactly what plays within the composition's duration — see Экспорт композиций.

If an effect plays at the wrong time

Check, in order:

whether the time cursor is inside the effect's bar — most often the effect simply hasn't started yet or has already ended;
whether the checkbox next to the effect's name is enabled and its opacity isn't set to zero;
whether the effect is covered by another one — one higher in this layout, or an effect in a layout positioned above it on the timeline;
whether it's the right layout: the bar may have ended up in a neighboring layout, so the effect plays on different fixtures — see Moving Effects Between Layouts;
whether the starts of the bars line up, if several effects are meant to start at the same time: pull their edges together while holding Shift, otherwise a discrepancy of a frame or two will stay invisible on the scale but will show up in the animation.

Keep in mind: shifting and trimming bars in time isn't recorded in the undo history. Ctrl+Z will undo adding, deleting, or moving an effect to another layout, but it won't put a bar back in its previous position on the scale — that's restored by dragging it or through Set time.

Hotkeys

Action	Keys
Play / pause	Spacebar
Time cursor to start / end	Home / End
Step one frame forward / back	Ctrl + → / Ctrl + ←
Step 10 frames forward / back	Ctrl + Shift + → / Ctrl + Shift + ←
Snapping while dragging bars	hold Shift
Add effect to selection	Ctrl + click
Delete selected effects	Delete