Super Metroid Door Connections

[Scyzer]

Hey everyone!
So while reading another thread I realised that not a lot of newer people know much about connecting doors, or the fun things you can do with them. I know a lot of us older hackers have been over this information many times, but newer hackers have not. Hence this thread.

   
• The back of a door MUST be on the edge of a screen (IE, the Door BTS tiles themselves). They cannot be 1 tile away from the edge, or in the middle of a screen.
  [spoiler=Example]https://www.dropbox.com/s/hjuahw2ztdhyari/Door1.png?dl=0[/spoiler]
• The screen directly AFTER the door must be red, or the edge of the room itself. You cannot have a door on the edge of a screen if the screen after is blue or green.
  [spoiler=Example]https://www.dropbox.com/s/ehnqswws7e5w5dd/Door2.png?dl=0[/spoiler]
• Doors do NOT have to be centered on the edge of the screen. Every original door in SM is centered with exactly 6 tiles above and below each door, but you do not have to follow this rule.
  [spoiler=Example]https://www.dropbox.com/s/qk6mq9tb0fr90zx/Door3.png?dl=0[/spoiler]
• BOTH connecting doors must be at the same relative position in a screen. This means if you have a horizontal door that is 4 tiles from the top of the screen, then the connecting door must also be 4 tiles from the top of the screen. You can work around this with ASM to have different positions.
  [spoiler=Example]https://www.dropbox.com/s/cdw0ze1zfctq43t/Door4.png?dl=0[/spoiler]

[Quote58]

Good idea making this scyzer, I think there's probably a number of things most of us take for granted but aren't obvious to new comers when it comes to how certain parts of the engine work.
That being said it's actually pretty easy to allow doors to not just be on the edge of a scroll, which black falcon made a patch for years ago: http://metroidconstruction.com/resource.php?id=44
https://www.youtube.com/watch?v=WgXabP402ks

[dewhi100]

I did NOT take #4 into account when drawing out my rooms. Initially, I figured that SM would just load the destination room at whatever x or y is needed for the doors to align... Guess I have some extra work cut out for me.

[Quietus]

Just to quote the other thread, part of getting this working involves moving the door bubbles, not just the tiles:

But you /can/ use non centered doors, if the entire door is on one screen, however you will need to manually set the doorcap x/y in the door editor, so the doorcap spawns in the correct location.

[Scyzer]

That being said it's actually pretty easy to allow doors to not just be on the edge of a scroll

I should elaborate actually.

Doors need to be positioned in such a way that the *screen/camera* position is at the edge of a scroll, irrelevent of where the door is. It's just that a door being on the edge is the easiest way for this to happen. If you have a 1x1 room with no scrolling, the door can be literally anywhere in the room, because the camera's position is always at the edge.

Of course, the easiest work around for this which always works is to have a small ASM run at the start of the door code, after the screen fades completely to black, which just sets the camera's position to be on the edge of a scroll. That said, it's not often that one can make door transitions from the middle of a room look good, so it's easier to just have them on the edge.