Adding 7th special stage in Sonic 1

SonicVaan got us started but there's more stuff we have to do. We could not find a thread anywhere on how to add a 7th special stage to a Sonic 1 hack. Not even on Sonic Retro. I knew somone named Cinossu made a Sonic 1 hack that features a 7th special stage. It was called Sonic 1: Extended Edition. There was actually a possible total of 14 emeralds to collect. If anyone goes to Sonic Retro to look up anything about Cinossu's hack, you'll understand what I'm talking about. We do know ASM, but we just want to know how it's done. I was thinking that it was similar to adding an extra level. By the way, I just formed a new hacking team called Team SonZX0. willj168 (myself), bareirito, SonicVaan, and CarrascoZX0 are part of the team. Before you say anything unhelpful, we do have ASM knowledge. We just want ideas.

 

Yeah it is the same as adding a new level. There is a RAM address for the number of special stages and a RAM address for the number of emeralds. Try extending these somehow and you will have a 7th special stage.


$FE58 is the chaos emerald number.


$FE16 is the special stage number.

 

What layout would the 7th special stage look like unedited? And how can I fit the 7th emerald into the ending sequence? Editing the mappings to make room for the 7th emerald?

 

1. There would be none; you'd be calling a file that, until you created it, wouldn't exist.


2. Essentially, yes.

 

So is it a good idea to duplicate one of the SS files so that way, I would have an existing file?

 

Adding a 7th special stage is easy enough. You basically just need to add 1 in several places. I did that in my hack at a certain point, and I effectively had 7 working special stages. However, as you probably know, I ended up keeping only 6 special stages. Why? Because adding a 7th emerald, instead, isn't as trivial as adding a 7th special stage, because the object IDs for the emeralds are 6 distinct ones, and both the ID above them and the ID below them are taken. Because of the way the code works, the emerald IDs must be contiguous, so you're pretty much screwed unless you do a massive ID renumbering or edit the code in some way. Sure, it is't that hard and I got it almost working at a certain point too, but I gave up because of the hardest (for me) issue: the palette used by the emeralds. I'm not an artist, so that completely screwed me up. And this is why I ended up keeping 6 emeralds, but 7 special stages (although the last one doesn't contain an emerald and is used as a bonus stage instead).


Self-plug.

 

I can fix the palette when we add the emerald. And Bareirito and I are understanding ASM a little better. One of his friends is teaching him ASM and thanks to your reference, we can get this done. Those are some good clues you provided us.


We already did music ports earlier. Just FYI. We got that taken care of.

 

I am still worried about the palette, in some places (for example, the ending sequence, the palette is completly full of another colours), so, how would we put more colours?


BTW, hi everyone I'm Ramiro, i'm new ....