Can't really explain this one

I was doing some sonic 1 hacking, changing sonic' starting position in act 3 of Green Hill Zone, Labyrinth Zone, Marble Zone, Star Light Zone, and Spring Yard Zone so act 3 would be boss only. I've had two problems: one isn't such a big deal but in Labyrinth Zone you start right before the boss on the other side of the shield monitor, as soon as the act starts your underwater so I placed some bubbles with SonED2 but they won't show up like I side it's not a big deal it's easy to get through. The real problem is with Green Hill and Marble. Sonic starts where the lamposts were (I deleted them) but in Green hill there is a strip with just blue no background.





I have this same problem in marble but it starts at the boss area itself.





Also I followed the guide for changing Sonic's starting position exactly and I ported the Rev 01 background effects if it helps any.

 

Hmm... That's a weird one. Maybe the background gets deformed beyond what exists? In SonEd2, add another background tile (or 2 ) in the background plane. I don't remember what key brings that up, but I think it is K.

 

The VDP's scrolling is based around a small mapped area, it can be about 512x512 big (although in Sonic 1 it's set the VDP to 512x256), the screen is smaller than this size meaning it cannot see all of the plane area at once, but it can scroll around that area, and if it reaches the edge of the mapped area and passes it, it wraps round to the other side, basically a 512x256 mapped area looping itself over and over again.


The area where the screen cannot see is the voided area, the trick is, as the screen is moving along this small planed area looping, you draw new tiles in the voided area, when the screen comes into that area, it gives the illusion that there is an endless level 100 time bigger than what actually exists. Sonic Team have two routines for this, one to draw outside the voided area while the screen is moving, and one to draw all tiles within the screen area at start of a level.


There's a problem with this though, the BG's position won't all be matched thanks to deformation, one way of fixing this would be to change the routine that draws the entire screen, to draw the entire planes insted, this will ensure that the tiles are drawn where they're meant to be (Not perfectly, but it being a BG and probably a looped pattern, no one's gonna notice).


Of course I have read somewhere that simply adding chunks to the BG works, though I don't know if this is in any relation to your issue.

 

I tried doing that in SonED2 but when I try to edit the background in green hill it doesn't go as far as the hex location 275003B0 it goes to the hex location 1D800000. In Marble Zone when I try to edit the background SonED2 goes as far as the Hex location 14800000 when I need to go as far as the hex location 163F0268. Is there any editors that can edit the background and go that far?

 

About the bubbles, their bits should be 1000000, you may want to check they're set correctly.

 

You can extend SonED2's BG to go that far. But everyone would know that if they read the readme! It's CTRL + Left/Right I believe.

 

I had this problem with Harder Levels v0.3.


Simply open up this level background in SonED2, so extend it more to the right adding more 256x256 tiles to there. This will solve the problem. Simple like Irix said. That was the solution. That worked with me, at least.

 

Just to add, you MUST be in the Level Edior (Plane A or B ), NOT the Object Editor!


EDIT: God I hate the B) smiley.

 

Ya I know that already .