Micro Machines 2 (Game Gear)

[Maxim]

Let's see how far this goes... hacked for mapping but I might make it a bit more interactive...

[Maxim]

So I made the hack so it's interactive (d-pad controls camera). Here we go...

[Maxim]

Bear in mind these are on a system with the same resolution as a Game Boy... it's like painting a room with a toothbrush They also take forever to PNGOUT on my netbook...

[Maxim]

I'm skipping the bonus games for now as they are quite hard work.

[Maxim]

Just in case it gets lost before I finish, here's the hack:

Code Select Expand

.memorymap
slotsize $4000
slot 0 $0000
slot 1 $4000
slot 2 $8000
defaultslot 2
.endme

.rombankmap
bankstotal 32
banksize $4000
banks 32
.endro

.background "mm2.gg"

.define scrollx $c137
.define scrolly $c139

.unbackground $69 $ff

.bank 2 slot 2
.orga $bc0f
.section "Hack redirection" overwrite
  jp hack
.ends

.bank 0 slot 0
.section "hack" free
hack:
  ; get inputs
  in a,($dc)
  ld b,a
  ; Y
  ld hl,(scrolly)
  ld a,h
  or l
  jr z,+
  bit 0,b
  jr nz,+
  dec hl
  dec hl
  dec hl
  dec hl
+:bit 1,b
  jr nz,+
  inc hl
  inc hl
  inc hl
  inc hl
+:ld (scrolly),hl
  ; X
  ld hl,(scrollx)
  ld a,h
  or l
  jr z,+
  bit 2,b
  jr nz,+
  dec hl
  dec hl
  dec hl
  dec hl
+:bit 3,b
  jr nz,+
  inc hl
  inc hl
  inc hl
  inc hl
+:ld (scrollx),hl
  bit 4,b
  ret nz
  ; return to game
  ; what should happen but we overwrote it...
  ld a,($c126)
  ; where we came from
  jp $bc13
.ends

Assembles in WLA DX (wla-z80). Any time the game scrolls to the player, i.e. when the race starts, when you respawn or go through a pool table, it will enter a state where the D-pad scrolls the camera (via the game's camera motion smoothing routines). Press 1 to exit this state.

[Maxim]

Four attachments per post...

[Maxim]

...is annoying when you have six maps.

[TerraEsperZ]

Impressive work! And you have *no* idea how jealous I am of your ASM skills...

[Maxim]

I'm not sure I could go back to making maps the old-fashioned way

[Maxim]

The last two challenge tracks and onto the Super League. I still need to do those bonus levels...

[Maxim]

A little more hacking and I know how to hack the levels. There are 36 in total, but at least two have names but no level data (the basement stages), so I'm about 70% done. Remaining levels:

Raining Champ
Turbo Turns
Step On It
Water Chase
Frosty Reception
Jelly Jitters
Turbo Blast
Picnic Problems
Plate Hop
Ferry Fiasco

The level numbers are stored in ROM at $3a684 for the Super League followed at $3a694 for the Challenge mode. 2-player lets you choose between the first 19 of them all.

[Maxim]

I just did another three in my lunch break... Raining Champ doesn't have any "rain" layer because I prefer it without.

[Maxim]

Almost done... except I need to align some of the others to the 96x96 grid, and the bonus levels.

[Maxim]

And that's all the regular levels.

[Maxim]

Finished, posted at http://www.smspower.org/Maps/MicroMachines2-GG and emailed to Jon.