S2 Early prototype GHZ fix

This hack is really good, I don't know what else to say, but will here be another version with Fixed Eggman art, and maybe another zone to replace LZ?

 

Great stuff. One thing I noticed is that the spikes don't show up and the signpost art is still garbled, but other than that awesome work.

 

Really? Signpost was fine for me.

As for the spikes, I think they removed the spike art from the ROM altogether so there's nothing to restore. (Confirmation of that would be nice though...?)

 

Awesome job. But although GHZ's collision is fixed, the rest of the levels' collision is fucked.

-Nick O.

 

My best reason for that is as follows:

For level collision, every 16*16 level tile mapping has a collision number assosiated with it. The number is used to read off a global collision table which describe which pixels are solid (well, columns of pixels, really) and how steep the slope is. The global table is appearently different in Sonic 2, but GHZ uses numbers refering to the Sonic 1 table. If you pay attention to the beta, the messed up collision in GHZ happens predictably on slopes; the "flat 16*16 mapping" collision is still correct. The Game Genie code seems to change the global collision table to match Sonic 1's.

If one went and fixed the 16*16 mapping collision table for GHZ to use Sonic 2's new global collision table, it would probably be possible to make the collision for the Sonic 2 levels and Sonic 1 to work at the same time. (However, you'd have to look though the global collision table to find by hand to find correct entires. And this assumes Sonic 2's global collision table has entries that match up to the old ones in Sonic 1.)

But... I really haven't stopped to look at how the beta and this fix works... it just appears to me to works out like this.

(Note: This post has not been proofread.)

 

Excellent work, Rika! =P

Hmm, with the graphics back in place, you can see that the mappings for the Meleon / Newtron badnik have been altered slightly; while the 'blue' ones are exactly the same, the 'green' ones no longer use the second palette line..

 

I nodiced that Eggman's wrecking ball has some of it's grapics back.

 

Plaaying through GHZ now is almost like playing through any other level. The garbled gfx should probably go back where the spikes go though, in their case garbled gfx is better than no gfx.

 

Good, it works. But the 2p mode is getting worse ... I want GHZ 2P working!

 

Nice work on the hack, Rika Chou. This was the best thing, since Hivebrain tried porting Green Hill into Sonic 2 Final, a while back. By the way, I noticed ONE other bug:


I don't know if this screen explains it enough, but on the part with the crumbling floors, Sonic will fall right through it.

 

How about a version without needing game genie codes, for those of us who don't have Game Genie-supporting emulators?

 

You can always convert them to hex yourself and apply the changes in any hex editor. The conversion tool was included in ESEII IIRC. Also, don't forget that if these changes are always enabled they'll fuck up collision for all other levels.

 

You could always run a little compare routine to make the game load the S1 array for GHZ and the S2 array for all the rest. It shouldn't be too hard to pull off, even in hex.

 

Um, Tails in EHZ?

What about making HTZ bigger so that you can finish the level, or finishing HPZ?

 

Can you fix boss' graphics?

 

My suggestion should be easy to implement. How about adding the correct level names in the level select.

 

Yeah, that's easy, as it's the exact same straightforward format as Sonic 1. Just find it in S1 rev 01, grab a good snippet of hex bytes (like 16 or 24) and then search for them in this proto. Here are the charset mappings, one byte per char:

Code (Text):

1. Hex  Character
2. ---  ---------
3. 00   0
4. 01   1
5. 02   2
6. 03   3
7. 04   4
8. 05   5
9. 06   6
10. 07   7
11. 08   8
12. 09   9
13. 11   A
14. 12   B
15. 13   C
16. 14   D
17. 15   E
18. 16   F
19. 17   G
20. 18   H
21. 19   I
22. 1A   J
23. 1B   K
24. 1C   L
25. 1D   M
26. 1E   N
27. 1F   O
28. 20   P
29. 21   Q
30. 22   R
31. 23   S
32. 24   T
33. 25   U
34. 26   V
35. 27   W
36. 28   X
37. 0F   Y
38. 10   Z
39. FF   Space
40. 0A   $
41. 0B   -
42. 0C   =
43. 0D   -> (right arrow)
44. OE   -> (right arrow)