Summary: Add the ability to change the Atlas Image of a Simple Tilemap object at runtime via events or actions.
Problem / Motivation: Currently, the Atlas Image assigned to a Simple Tilemap object is static and can only be set at design time. There is no built-in action or expression to swap it during gameplay. This becomes a significant limitation in scenarios where the game world needs to visually transform on the fly. For example:
- Transitioning between seasons (summer → winter → autumn)
- Shifting between game states (normal world → corrupted/cursed world)
- Applying environmental effects (day/night tile themes, flooded levels)
- Supporting multiple visual themes without duplicating scene objects
Proposed Solution: Introduce a new action under the Simple Tilemap object category, such as:
Change atlas image of
[Tilemap object]to[image resource]
The new atlas image should use the same tile dimensions and layout as the original, so the existing tile mapping data remains valid and the visual swap is seamless.
Acceptance Criteria
- A runtime action exists to change the atlas image of a Simple Tilemap object
- The change takes effect immediately on the next frame
- The tile layout and collision data are preserved after the swap
- The action is available in the events editor like any other object action
Alternatives Considered: Using multiple hidden Tilemap objects and toggling their visibility is a workaround, but it is memory-inefficient, harder to maintain, and does not scale well for large or complex maps.
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