Room Generation from Image - "Read pixels" Extension (Usage)

How do I...?
1

Hello community!

I’m creating a 2D room generation system in GDevelop where the layout is defined by a “blueprint” image (e.g., 11x11 pixels), with colors representing different tiles (wall, floor, etc.).

My goal is to:

  • Load the “blueprint” image into a Sprite object (RoomBlueprint).
  • Iterate through each pixel of the blueprint.
  • Read the RGB color of each pixel using the “Read pixels” extension.
  • Based on the color, create the corresponding tile (e.g., WallTile, FloorTile) at the correct coordinates.

My main question is: Can the “Read pixels” extension be used to implement this room generation system as I described? If so, what is the correct and complete syntax for reading the RGB (Red, Green, Blue) values of a specific pixel from a Sprite object using this extension?

Any help or event examples would be greatly appreciated!

Thank you!

2

The extension only allow to read pixel that are displayed on screen. With JavaScript, it’s possible to read the pixels of a given image resource.

If you don’t know how to code, you might find someone interested by the idea. It won’t be easy since there is a bit of memory management to do to make it efficient.
You could open a feature request in the extension category and see:

I guess a workaround would be to display the sprite on screen of only 1 frame, but it may not look great if it does some kind of flash.