Runtime Atlas

This serves as both an exampel and a library to help you create atlases at runtime.

Installation

You can use the runtime atlas in your own project by adding this project as a Defold library dependency. Open your game.project file and in the dependencies field under project add:

https://github.com/Jerakin/defold-runtime-atlas/archive/refs/heads/main.zip

Or point to the ZIP file of a specific release.

Quick Start

You only need to supply a list of images as well as width and height to rtatlas.pack() use it.

local rtatlas = require "runtime-atlas.runtime-atlas"


local atlas_entries = {
    "example/assets/images/image0.png", "example/assets/images/image1.png"
}

local atlas_id = rtatlas.pack("example", atlas_entries, 256, 256)

go.set("#sprite", "image", atlas_id)
sprite.play_flipbook("#sprite", "image0.png")

The images added will be added with the full file name as the id. This always includes the .png.

API

rtatlas.pack(atlas_name_or_path, list_of_textures, width, height)

Packs the provided list_of_textures into an atlas

PARAMETERS

• atlas_name_or_path (string) - If an path is provided it will load the texture at that path and update image data on it. If a name is provided a new atlas will be created.
• list_of_textures (table) - A table of your images, these images needs to be available as resources.
• width (number) - The height of your atlas
• height (number) - The height of your atlas
• options (table) - Optional table.
  • premultiply_alpha ( boolean) True if alpha should be premultiplied into the color components. Defaults to false.

rtatlas.algorithm

Property which is the function that will be used to pack an atlas with. A simplistic rowpacking algorithm is provided as the default

Packing Algorithm

If you want to write your own algoritm the signature should be

algorithm.pack(list_of_textures, width, height)

PARAMETERS

• list_of_textures (table) - table of images to pack, each image is represented by a table {name, w, h} you are expected to return an extended version of this table where entries for positions {x, y} have been added.
• width (number) - The height of your atlas
• height (number) - The height of your atlas