Unity and plugins provide many great ways to build Sprite Sheets. However they're used directly into Unity Editor or with an external software which is perfect in many case, but none provide the ability to generate SpriteSheets at runtime.
The RectanglePacking algorithm is a port of the AS3 version made by Ville Koskela. Assets used in the demo come from Kenney.
You could combine the generated Sprite Sheets.png with a pngquant compression via this script PngQuantNativeProcess.
Please note that Unity provides a Texture2D.PackTextures method, I didn't test it nor made benchmark performances.
Add the AssetPacker component to your GameObject:
using DaVikingCode.AssetPacker; using System.Collections; using System.Collections.Generic; using System.IO; using UnityEngine; using UnityEngine.UI; public class AssetPackerExample : MonoBehaviour { public Image anim; AssetPacker assetPacker; void Start () { string[] files = Directory.GetFiles(Application.persistentDataPath + "/Textures", "*.png"); assetPacker = GetComponent<AssetPacker>(); assetPacker.OnProcessCompleted.AddListener(LaunchAnimations); assetPacker.AddTexturesToPack(files); assetPacker.Process(); } void LaunchAnimations() { StartCoroutine(LoadAnimation()); } IEnumerator LoadAnimation() { Sprite[] sprites = assetPacker.GetSprites("walking"); int i = 0; while (i < sprites.Length) { anim.sprite = sprites[i++]; yield return new WaitForSeconds(0.1f); // loop if (i == sprites.Length) i = 0; } } }