Originally posted by Yoshifan0204
Now I know that hacking is not as easy as I thought before!
But I still have more questions...
4) I think making by golden egg is not enough for make auto-scroll levels. Can you tell me how to do that? (if hex editor is require, please give me a good one)
5) Same with 4, but how can I make skiing yoshi?
6) Please tell me more about ''Item memory''. I don't understand when I edit mid-way entrance.
4. The auto-scrolls are a bit tough to deal with due to how they actually work. Take the 1-5 auto-scroll, if you want to use it in another level then you have to build the level around where the auto-scroll takes you. The special auto-scrolls like the one in 1-5 move to a final point in the level that is already set. If you want to change how the special auto-scrolls scroll then you do have to use a hex editor. The one to use for this is Translhextion 16c but first you need to add a header to the ROM that you use. To add a header you need HeAdder.
If you do use the hex editor be sure to check out the Yoshi's Island FAQ section because there were several posts there where they mention how to edit special auto-scrolls.
5. Actually you can make a skiing Yoshi in pretty much any level. Skiing is one of the different exits that Yoshi can have. Go to the pipe in Golden Egg that says "Open Screen Exit Editor". Before you do anything with exits press 3 to show the many sub-areas of the map.
In this screenshot you can see that the screen 04 is highlighted in red. This is because there is a screen exit there. The door sprite 093 can be placed anywhere and will work anywhere but if you put it or a pipe or teleporter in a place without a screen exit then it'll spit you out at the top of level 00 so make sure to only use those things in places with screen exits.
Now to make a screen exit. You see next to the 04 there is a 01 X:68 Y:07? Those are the coordinates of where the exit, the door go. I know it sounds tough but it really isn't so just bear with me. In the exit editor first go to the screen "Target Page" where you want the exit to be. Next select "Enable Screen Exit". Then you need to pick exactly where you want Yoshi to come out of and in which level. In the screenshot the 01 means that when he enters the door in screen 04 he'll come out of the door at the X value of 68 and the Y value of 07. When dealing with door exits you need to remember that the value you use will be where Yoshi's HEAD pops up so you need to select a value one square above where the door sprite is. With pipes going up you need to point to the space one above the lower left corner of the pipe and with pipes going down you need to point to the upper left corner of the pipe.
Now that exits are all taken care of you can choose what kind of exit to use, skiing being one of them. In my screenshot you can see that I made a sort of mini-copy of the opening area on the left. That is because the special animation of Yoshi going into the door and exiting as skiis is only available in 5-3 and 5-E. You can still put skiis in any level but there won't be that special animation and so far there isn't anything that can be done about it.
6. Item memory, I think, is how many sprites can be on the screen at the same time. Something VERY IMPORTANT to remember with item memory is to try to not put things that you can collect like coin SPRITES one right above the other since they may disappear. Same goes for any other sprites and red coins. Say you have a red coin in the air and the you put a Goonie sprite two spaces under it. The red coin now may disappear due to an item memory glitch. This glitch is present in every level and you have to do everything you can to avoid it or else you won't be able to 100% the level.
The other kind of item memory in the header editor refers to middle-rings. You can have up to 4 Middle Rings in a level. Say your first room in a level is 01. If you set the "Item Memory" to 0 then you'll be able to put a middle ring in. Now if you want to change where the middle ring goes when you restart from it or how many middle rings there are in the level then you'll need the middle ring and level entrance editors. You can find them in Kipernal's Generic YI Editing Tools section of the forum.
Speaking of middle rings and their locations, you will HAVE TO edit middle rings if you want to move them to some other spot in the level, add them, or move them to a different level.
Continuing on the first mid-ring is in 01 with sprite memory at 00, the second is in 3A with sprite memory at 01 and the third is in 3B with sprite memory at 02. This is an example of how to use the sprite memory tab of the Header Editor.