Quick answer: Construct 3 spritesheet's frame boundaries shifted after resizing the source PNG? Frame coordinates stored as absolute pixels - resize invalidates them.
Updated a character spritesheet by adding more frames at the bottom. Existing frames now misaligned.
Re-import frame layout
Image editor > Re-import frame layout. Click each frame to redefine bounds.
Use power-of-2 grids
Frames at fixed cell sizes (64x64, 128x128). Resize is grid-aligned; frame boundaries stable.
Or use frame-relative imports
Some Construct importers store frames as relative offsets. Survives resize better than absolute.
“Spritesheet imports cache pixel coordinates. Coordinates rot when the sheet changes.”
Decide on a grid early; document. Frame additions append to the grid; existing frames stay anchored.