I take it the stairs are not separate objects like in the NES games?
Are the stairs hardcoded to the 32x32 blocks or are they perhaps hardcoded to the 8x8 tiles themselves?
Or, hope of hopes, they are simply a tile attribute?
As far as I can tell all collisions (including stairs) are stored for each of the 16 tiles in every 32x32 block (4x4 tiles). So a level could mark every tile with a unique collision property. I'm certain it's per tile, but what I haven't looked into is the source of the data for the collison table in RAM at 7E:4000. I think the data is associated with the block which means the same tile can have a different collision property based on which block it's in.
Scratch that. It's per tile, but each level has a table in ROM that says all tiles in a range are a certain collision type. So the tileId (tile character number referred to by the tile map) along with the table tell you if it's a step, a wall, or empty space.
Make sure you add the undo button I requested in my last post. Maybe have it do a couple undos. Will it allow you to edit cutscenes too? I mean like the intro and ending? I don't need to anymore, but being able to edit the palette would have been useful in my hack.
I'd like to have an undo, but not sure how to easily add it so it's really low on the list of things to do. Don't expect it any time soon. I don't plan on supporting editing of cutscenes unless you mean just decompressing the graphics. Things I would like to add:
event trigger/object display
event trigger editing and placement
Anything missing from the list is not being considered right now. And the stuff on that list is going to take weeks to figure out.