Ball Trails
Every Ball Trails control: infinite trails, trail border, colour modes including animated gradients, length, thickness, glow, width taper and spawn spacing.
How Trails Work
A trail is a string of shapes left behind the ball as it moves. Short trails add motion blur; long or infinite trails paint the ball's whole path, which is the classic light-painting look.
The Ball Trails panel is in the Arts tab and needs every plan, including Free. It only appears in modes that draw a 2D trail: it is hidden in 3D modes and in the few 2D modes that never draw one. The same switch is also offered as the Line Trail Engine add-on in the Engine tab.
Trails are on by default, with a length of 30. If you see no trail, check the Ball Trails switch at the top of the panel.
Trail Switches and Border
The panel opens with the main switch, then a small Trail Border box.
| Control | What it does | Range / default |
|---|---|---|
| Ball Trails | Turns trails on or off. | On |
| Infinite Trails | Trail pieces never fade, so the whole path stays drawn. | Off |
| Width (Trail Border) | Thickness of an outline around each trail piece. | 0 to 10. Default 0 (no border) |
| Border Color | Colour of that outline. | Default white |
| Border on Permanent Trails | Keeps the outline on Infinite Trails too. | On |
Trail Color Mode
Trail Color Mode sets how the trail is coloured along its length.
| Option | What you get | Extra controls |
|---|---|---|
| Solid Color | One colour for the whole trail. | Custom Trail Color (default white) |
| Rainbow (Static) | A rainbow spread along the trail. Default mode. | |
| Rainbow (Animated) | The rainbow flows along the trail. | Animation Speed 0 to 5 (1) |
| Gradient (Static) | Your own 2 to 4 colours blended along the trail. | Gradient Colors, Add, remove (x), Color Cycles 1 to 20 (1) |
| Gradient (Animated) | Your gradient flows along the trail. | Gradient controls plus Animation Speed -5 to 5 (1) |
Tip
- Color Cycles repeats the gradient along the trail, so the colours tile instead of one colour filling most of it. On Infinite Trails the bands stay a fixed size and stay painted in place.
- A negative Animation Speed on a gradient flows it backwards, away from the ball.
Length, Opacity, Thickness and Glow
These sliders shape the trail itself.
| Control | What it does | Range / default | Tip |
|---|---|---|---|
| Length | How many pieces the trail keeps. | 0 to 200. Default 30 | Longer trails cost more; a cost dot shows how heavy it is. |
| Fill Opacity | Transparency of each piece. | 0 to 1. Default 1 | Below 1, overlapping passes build up density where the ball has been most. |
| Stroke Opacity | Transparency of the trail border. | 0 to 1. Default 1 | |
| Trail Thickness | Width of the trail relative to the ball. | 0.1 to 10. Default 1 | |
| Trail Glow | A glow around the trail. | 0 to 50. Default 0 | Looks best on a dark background, and adds preview cost. |
| Starting Width | Size of a piece when it is created. | 0.1 to 3. Default 1 | Greyed out while Match Ball Size is on. |
| Ending Width | Size of a piece just before it fades. | 0.1 to 3. Default 0.1 | Greyed out while Match Ball Size is on. |
| Match Ball Size | Each piece takes the ball's exact size at that moment and ignores the two width sliders. | On | Keeps infinite trails steady even if the ball grows later. |
Spawn Spacing
These decide how often a new trail piece is laid down.
| Control | What it does | Range / default |
|---|---|---|
| Time Spawn Interval | A new piece every this many milliseconds. Greyed out while Spawn by Distance is on. | 1 to 500. Default 20 |
| Spawn by Distance | Lays pieces by distance travelled instead of time, so a fast ball and a slow ball leave an equally dense trail. | On |
| Distance Spawn Interval | Pixels the ball must travel before the next piece. | 1 to 100. Default 5 |
Tip
- Keep Spawn by Distance on for smooth, even trails. Switch to time spacing only if you want gaps to open up as the ball speeds up.
Trail Launch Settings and Border Break
The panel ends with Trail Launch Settings (Launch Offset X and Y from -500 to 500, Launch Angle 0 to 360, Launch Speed 0 to 100) and the Show Shards on Border Break switch.
Show Shards on Border Break (off by default): when a ball that grows at a steady rate reaches the arena wall, it shatters into shards and the run restarts about 2 seconds later. It does not fire while the ball uses Timed Growth.
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