Guide

Why slot win animations start and end on the static symbol

A win animation that starts and ends on the exact static symbol can take over from the reel symbol, and hand it back, on any frame without a visible jump. Here is where a mismatch shows, why loops are different, and how to check it.

Published 8 October 2026

The short answer

On the reels, a symbol at rest is a still picture. When it is part of a win, the game swaps that picture for an animation, and when the win is over it swaps back. If the animation's first frame is not exactly the still, the swap shows: the symbol flickers, shifts or changes colour for a frame. An animation that starts and ends on the still makes both swaps invisible.

Where a mismatch shows

• At the start of a win. Every symbol in the winning line switches from still to animation on the same frame, so a mismatch shows as the whole line flickering at once.
• At the end of a win. The animation hands back to the still. If its last frame is off, the symbol snaps into place after the celebration.
• When clips follow each other. A wild that lands and then wins plays two clips back to back. When both start and end on the still, any clip can follow any other.

How it looks in a PixiJS game

With the GreatSprites runtime, an element rests on the first frame of its first clip, which for a one-shot is the still, and play() resolves when the clip is back on the still:

const wild = await gs.object('./sprites/object-1/', { height: 160 });
reel.addChild(wild);        // shows the still
await wild.play('win');     // resolves back on the still

Because the clip ends on the same picture, the game does not have to hide the animated element and show a static one when the win ends: the element can stay in its cell. Every cell showing the same symbol draws from the same loaded animation, so fifteen winning symbols cost the memory of one. Playing clips has the details.

Wins, idles and landings

The same rule holds for the three clips a slot symbol usually has: the win, a calm idle now and then, and a land as a wild or special symbol arrives. Each begins and ends on the art, so the game can play any of them at any time, and at rest the symbol always looks exactly like your art.

Loops are the exception

A loop keeps moving for as long as it is on screen: a flickering flame, a spinning coin. It never stops on the picture, so it moves in place on the picture's footprint instead. Use a loop for a symbol that should always move, and a one-shot for a moment such as a win.

How GreatSprites checks it

Every animation GreatSprites makes is checked automatically before you see it: it must start on your picture, return to it, and leave no stray colour around its edges. One that fails is made again at no cost to you.

If you animate by hand

Key the first and last frames to the exported still, export the still from the same file as the animation, and check the swap in the game at the size it is drawn, not in the animation tool. A one-pixel shift or a slightly different colour at the edge is enough to show as a flicker on a phone.