Coin tab
The flying thing itself. It is called a coin, but it is whatever picture you give it: a gem, a dragon, a walking tree, the head of a win line.
The top of the tab has the usual three: Show coin (the master switch), Mute and Solo. Below that is everything about how the coin looks and turns. In the Atmospheric and Flow journeys the tab is called Item and the switch reads Show item; everything on this page applies to the item in the same way.
The picture, Transform, blend mode, size, opacity and tint work exactly as on every other layer - they are explained once in Controls you meet everywhere. That includes the flat Opacity slider under Blend mode, the same knob the layers have in Look; the Opacity over life curve multiplies on top of it. This page covers what is unique to the coin: the flight visual, rotation, and the emitters.
Flight visual - Plain circle is a debug dot; Animated PNG coin is the picture sequence. In Win lines it reads Animated PNG line head, in the Atmospheric and Flow journeys Animated PNG item, where the bundled picture is a soft white disc the tool draws itself and each preset brings its own placeholder (a streak, a flake, a bug, a bubble, a smoke puff, a glow bulb). Upload your own to replace any of them.
Switch to the plain circle when you want to judge a trail without the coin art distracting you. It is faster than muting and unmuting.
Variants - several pictures in one system
In the Atmospheric and Flow journeys only, a collapsed Variants group sits under the item's picture. It holds extra image sets, so one system can show three different fish, four butterflies or two kinds of leaf instead of copies of one picture.
Add variant (upload images) - uploads another picture, or another whole numbered sequence, as one more look for the item. Up to eight. Each variant gets a row showing its frame count and first file name, with a Remove button.
Upload your first fish as the item's main picture, then add the other two as variants. Every item wears the main picture or one of the variants for its whole life, with equal odds, so three looks means roughly a third each.
A variant is only another set of frames: Playback, Sequence FPS, Start frame and Frames come from the main sequence and apply to all of them, and so do Transform, tint and the curves. There is no size normalising, so a bigger picture draws bigger - crop your sets to the same size if you do not want that. Loading a preset drops the variants along with the other uploads.
For a field of one picture per item out of many, without uploading each as a variant, use Frames set to Random image on a single upload of thirty snowflakes instead - see Controls you meet everywhere. Variants are for a handful of distinct looks, each of which may itself be animated.
Tint along the flow
In the Flow journey only, the item's tint controls have one more dropdown under the tint gradient.
Tint runs over - The item's life reads the gradient from birth (left) to death (right), like every other tint in the tool. The field reads it from the start of the spine (left) to its end (right), so the colour belongs to the place, not to the age of the item.
Genie smoke: pink on the left of the gradient, violet on the right, and The field. Every puff is pink at the spout and violet by the top, whether it rose fast or slowly.
It only colours the item. Trails and sparks riding on it keep their own tint over their own life. Tint over life has to be on for either choice to show.
Rotation
Three separate ideas live in this group, and mixing them up is the usual source of confusion: which way the art points, whether it turns to follow the path, and whether it spins.
Align to flight path
Align to path - turns the coin so it faces the direction it is travelling.
On for anything with a nose: an arrow, a comet, a dragon. Off for something symmetrical like a coin or a ball.
Art faces - which way your picture points as it was drawn: Right, Left, Up or Down.
The maths treats right as forward. A dragon drawn facing left needs "Left" here. Getting this wrong is why art sometimes flies backwards, and the fix is this dropdown, not a 180° rotation somewhere else.
Fine offset - a few extra degrees on top, for art drawn at a slight tilt.
Keep upright (mirror to face travel) - instead of turning the art upside down when it travels leftwards, it mirrors it.
Essential for anything with a readable up and down - a character, a creature, lettering. A fish swimming left should be mirrored, not upside down.
Spin
Rotations - how many full turns the coin makes over the whole flight. 0 is no spin.
2 to 4 turns reads as a coin tumbling. More than about 8 turns in a short flight becomes a blur.
Direction - clockwise, counter-clockwise, or random per flight.
Random is nearly free variety when many coins fly at once.
Start angle and Random start angle - the angle at launch, and whether each flight picks its own.
Random start angle stops fifteen coins launching in perfect formation.
Spin speed (curve) - when the turning happens, not how much. The total always matches Rotations.
Preset Fade in: the coin leaves still and winds up as it flies. Fade out: it spins fast off the line and settles before landing, which reads as "arriving" rather than "stopping".
Wobble
Wobble amount / Wobble speed - a gentle rocking added on top of everything else, in degrees and in cycles per second.
5-10 degrees at 2-3 cycles per second makes a floating object feel alive. Leave it at 0 for a hard, fast coin.
[coin_01 - The Rotation group of the Coin tab, expanded, panel width, with its Align to flight path, Spin and Wobble sub-groups open. No highlights.]
Emitters
An emitter is a point on the coin that trails and sparkles can come out of. Without them, everything is born at the centre of the coin. With them, you can have sparks fly off the rim of a spinning disc, or two butterflies circling a walking character.
You can place up to four, and each has a fixed colour - cyan, pink, lime, violet - which shows on the flying coin while Show pivots is ticked in the panel header, on its row, and on the edge of every layer card that uses it. That colour is how you keep track of which layer comes from where.
Angle - where the point sits around the ring, in degrees clockwise from the right.
Radius - how far it sits from the centre. 0 is the centre itself.
Set Radius to roughly half your coin's width to sit on the rim.
A layer picks its emitter with Emit from in its own card, on the Trails and Sparks tabs.
Ring
The emitters live on a ring, and the ring has its own settings. This is what lets the emitters behave differently from the coin.
Follow coin - how much of the coin's pose the points inherit.
- Coin art - the points are pixels of the picture: they take its spin, its path alignment, its size and its Transform. A rotating disc leaves spiralling trails. This is the normal choice.
- Coin size only - they grow and shrink with the coin but never turn with it.
- Nothing - a fixed ring in screen pixels around the path.
Use Coin size only or Nothing when the coin should not spin but something should circle it - the butterflies-around-a-walking-tree case.
Offset X / Offset Y - move the ring centre away from the path, in screen pixels. Not rotated or scaled by the coin.
Align to path - turn the ring with the direction of travel, so angle 0 is ahead of the coin and 180 is behind it.
Parked when Follow coin is Coin art, because the coin's own alignment already does this.
Rotations / Direction / Start angle / Spin speed - the ring's own spin, on top of anything inherited from the coin. Same idea as the coin's spin group.
Radius over life (curve) - multiplies every point's radius over the flight. 1 is as set, 0 pulls them into the centre.
Start near 0, swing out to 1.4 in the middle, come back to 0.2 at the end: the followers gather, spread and regroup before the landing.
[coin_02 - Stage crop around a coin in flight, about 900 px, with a rim emitter visible as a small cyan dot and the trail coming off that point instead of the coin centre. No highlights.]