11 March 2016 - Forum Rules

Main Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Topics - pangenttech

ROM Hacking Discussion / A Week of Garfield
May 09, 2022, 07:57:43 PM

We've been working on upgrading A Week of Garfield (Famicom/NES) with new graphics, and some other changes.

I've overhauled the title screen (and made other changes) but that's not released yet. (Four-legged Garfield has a little more animation.)

This has a reputation as a bad game, but it at least looks better now.

Our question is about the jump kick. Garfield has a kick attack, and can also kick when jumping, but no animation plays for the jump kick. We've been hoping to add an animation to this for awhile. We still have about three extra tiles which would be enough to animate with, or otherwise the standing kick's art could be used.

For no reason, the jumping, stretching and damage sprites are flopped in the ROM compared to the walking sprites. This has become relevant when messing with the code.

We can experiment with affecting the kick animation by changing ROM address 01D0EB from 09 to 00, and additionally changing 1D0F0 69 to A9.

EDIT: According to Rani, Game Genie codes SXSIIESU+ZESITALP+OKSSAEPX+IESSPALA+PESSZAES+ENSSZAEI+PVSSGESU+YESSIAZE+XVSSTALE+XVSSYEAO+OXVIAEPV rewrite the code enough to get us the standing kick in mid air.

More ideally we would load a construction at 3840 or some other empty space in the ROM, where we could insert new left and right jump kick sprite construction.

Otherwise it could load the standing kick sprite construction.

QuoteThat would take a different sort of code rewrite than the one I did. We would have to plot out what all the animation frame call numbers mean and possibly shift a few around. Watch RAM addresses 004F and 0342 to see what I mean.

Version with jump kick has now been uploaded:

   This is a hack of the Dr. Mario prototype "Virus," released in 2020.

Amilgi has surprised me by writing NSF music for Dr. Garfield, four themes in total. I'd like to figure out how to get these into the NES and Game Boy ROMS.

Music selection #3 seems to exist in the ROM from 006ECF to 0072C0, and selection #4 from 75D2 to 78AD. The original music is left over from Tetris. I can copy/paste data into that section and get a bit of a mess of noise. Song 2 in the NSF starts at F0D probably.

Pasting from NSFs of Tetris and Dr. Mario also only gets nonsensical noise, at least where I've pasted them.

QuoteSome notes:
- I only used the 2a03
- I didn't use any DPCM (could be used for drums if we wanted)
- I made one simple instrument to handle the arpeggio in the gameplay music. Some drivers/converters prefer no instruments & just tracker effects, while others prefer exactly the opposite. I can rework parts of the module if needed for easier implementation.

QuoteMost straightforward way is to inject Famitone or a similar sound engine into the ROM somehow.

Tetris disassembly:

  Also, about CHR bankswitching:

   Being a prototype, there is a fair amount of empty space in the ROM and the title screens and backgrounds are basically drawn uncompressed in full. This made it easier to hack.

The backgrounds in 1P and 2P mode bankswitch between the 0 and 1 CHR registers, to create some animations with the viruses.

For 2P mode, I would like to switch between the 8 and 9 registers, so I can do more with the background.

I can about halfway understand what the code is doing, but not enough to make this happen easily.

(Searching for 9F63 leads to the associated code, I believe.)

The added 8 and 9 CHR registers are also not recognized by the ROM at this point. I think something needs to be changed in the header?

  (Several CHR banks were already added to allow for sprite bankswitching on the title screen.)

  I asked about this previously, and got a confusing answer:

ROM Hacking Discussion / Dr. Hello graphics format?
April 11, 2022, 06:41:16 AM

   There is an unlicensed Korean Dr. Mario knockoff called "Dr. Hello," originally for MSX and ported to the Sega Master System.
   The two versions are very similar.

   Due to its unlicensed nature, it's not hard to find ROMs of the game.

   I have attempted to load the game's graphics into YY-CHR and Tile Layer Pro without success.

   Viewing it in the more complex Master System format brings up pretty much just garbled nonsense. Viewing it in a simpler format, like 1-color 1BPP, shows that the graphics are there, but no format seemed to work to display the graphics sensibly. I hoped that the MSX format would come close, but "close" is not close enough.

   Does anyone have any idea how to display these graphics accurately so that I can edit them?
I'm close to finished with a graphics hack of Mickey Mousecapade.

I need to change how some of the enemy and item sprites are constructed in the last two levels - what tiles they use and where (metasprite construction or OAM). My versions of some enemies are shaped a little differently, animate a little differently, use different tiles etc.

I have been unable, so far, to find the sprite placement data in the ROM. I searched for specific tiles and their palettes and did not find anything obvious in the hex. (Admittedly, the code is hard to read by sight.)

Mesen's Sprite/OAM RAM (in Memory Tools) is outputting valid metasprite data but I haven't yet spotted anything similar in the ROM.

I would be using Shiru's NES Screen Tool to rework the metasprite construction.

It's possible that there's some compression going on or an unusual format, or that the PPU is assembling bits and pieces of the CHR sprite sheets together, in a way that's different than expected, so the rows it's calling are different. It does that for the title screen, which I've already reworked. The emulators Mesen and FCEUX do not account for this, so I can't really be sure.

Maybe the game skips the palette byte, since every character in the game uses a single palette?

These are my notes on what I was looking for in the ROM (one expected tile and its palette)
71 00  Pirate boss
BF 01 Walrus
68 00 Queen boss   (A8 00?)
B6 00 or 02 Cake
A6 ? Diamond
E2, F2 01?? Strange Minnie?

More small questions:

There is a strange version of Minnie in gold on this sprite sheet, with reversed colors. I'm not sure if this actually appears in the game.

The game has a level select cheat, but it seems to mean that you don't get to see the Alice ending. I'm wondering if there's a way to skip to the ending for playtesting purposes.

Also if anyone has experience with ASM 6502 NES coding, I have some additional questions to ask you privately.
Hi. As a followup to the NES version of Dr. Garfield, I did a quick graphics hack for the Game Boy version of Dr. Mario, also for Game Boy Color.

This is based off of the Dr. Mario DX Game Boy hack by marc_max and Da_GPer, seen here:

This hack added color to Dr. Mario (making it a Game Boy Color game) and also created more NES-like graphics for the viruses.

I've worked on a few NES hacks and gotten familiar with that format. This is my first time attempting Game Boy and Game Boy Color.

I'm using Visual Boy Advance for an emulator, which can look at and export palettes. Not as good as Mesen for NES, but all right.

I don't know much about Game Boy Color palettes, how to generate them, and how to change them. Google searching hasn't been helpful on this topic.

The Dr. Mario DX game cycles through a few different palettes on the title screen and during gameplay. Some work better than others. I need a palette that's basically one color to work with my greyscale title graphics (or I'll have to simplify them).

Since I haven't changed Mario/Garfield's palette, he's a bit pink right now instead of orange.

There is a Mario happy "winning" sprite, I'm not sure where that shows up in gameplay.

I also don't know how to access 2 player mode for testing.

On an unrelated NES note, I am trying to learn how to enable custom music and custom backgrounds in Mesen HDPacks. There's a lot of discussion about this but not much good info, probably because it differs for each game and isn't done automatically by Mesen or related tools.
   First, I'm hoping to improve a previously-released project:

This is a version of Virus (1990 NES prototype for Dr. Mario).

There's lots of empty space in it, which may make hacking easier.

The video here is a "best case scenario," as it shows functionality which is not present in the ROMhack currently. I'd like to get it closer than I have.

Added in the video (but not in the ROM) are a four-frame running Odie sprite, loss animations for Odie and Garfield, and a win animation for the bulldog. I've included the sprites for these in the ROM but can't implement them. (Garfield's whiskers when throwing the pills are also implemented as background rather than sprites here.)

Music is also added for the video. I think the proto has Tetris music but it's disabled.

"The original music tracks are still present, and can be played by writing a track number to RAM address $6F5."

   Also: I have released an ambitious Tiny Toon Adventures NES hack, but am still interested in improving it.

   This changes the game's graphics to feature a different lead character, enemies, and cutscenes.

   Proveaux has been helping me with some technical issues.

   Can the Tiny Toon Adventures bosses be made more difficult, by requiring more hits to defeat? Thinking in particular of the too-easy pirate boss, and Dr. Gene Splicer.

  For some reason, Not Elmyra's head sprites are misaligned when she changes direction suddenly on an incline, which messes up her face by apparently pasting it over itself.

  I'd like to add an extra sprite or two to the right of Not Hamton the Pig, during his scenes.

Music can be disabled by changing 0182C5 C4 to C5. CC was crashing the game but I think C5 is fine.

   I wanted to disable music for my Youtube videos, so it can be replaced. I may reenable music for the public release. Ideally we could actually replace the Tiny Toon Adventures theme music, but I know that's very difficult!

   I recall I also wanted to slightly reposition some sprites when not Montana Max is defeated at the end of the game. (Sprites which change his color, and could be placed a little higher)

   As a cheat in an emulator, you can write 10 to 4C to skip to the ending.

   Minor things: The robot character who replaced Gogo Dodo has one sprite in the wrong position. And there's some errant chest hair on the ape/Wolverine boss.

  Tiny Toon Adventures uses sprites for some elements of the intro and ending, and I was tempted to rework this to improve the colors in my hack but only did this in a couple places. The title screen uses sprite text, though.
Personal Projects / Signal and Noise thread
October 18, 2020, 02:51:56 PM
Hacks from Youtube channel "Signal and Noise."

Find out why everybody's calling on Dr. Garfield.

(This may sting a little.)

Looking for an intense new challenge? Dr. Garfield is here and he's got the cure!

Three kinds of ugly, nasty viruses are on the loose. But these germs are fun to catch. Garfield throws multi-colored vitamin capsules into the bottle. You can move, shift or spin the capsules as they fall. Arrange them to align with other capsules on top of the virus. If you can get 4 or more of the same color in a row, POOF! The viruses disappear! Destroy all the viruses in the bottle and you progress to the next round, where things get even more difficult. Play alone or enjoy simultaneous 2-player action, only from Nintendo on your Nintendo Entertainment System or Nintendo Game Boy.

Dr. Garfield—the fun is contagious!

A Week of Garfield Minus Garfield.

Penguin Land NES

Sega's classic Doki Doki Penguin Land is ported to the Nintendo Entertainment System. Well, sort of. This is based on the unlicensed clone Duck Maze, with new graphics.

In this puzzle platformer, Adelie the penguin (aka Overbite) must carry his egg to safety in 20 tough levels, avoiding hungry foxes and brutish gangow polar bears.

Spice Girls Tiger Electronics LCD Handheld Game MAME 1997

Supported in HBMAME builds after July 31, 2019.

Heathcliff and the Garbage Ape (for Windows)

This is a Heathcliff reskin of Donkey Kong, or rather Mick Farrow's 2010 PC remake of the 1986 Ocean Software version of Donkey Kong for Commodore 64.

Every cat knows and loves the mysterious Garbage Ape- who arrives in the night to deliver trash to all good cats!

But now he's gone ape and kidnapped the lovely Sonya!

Now Heathcliff - America's 2nd favorite fat orange comic strip cat - must scale the steel beams while avoiding traps!

Good luck!

Super Spice World X
Spice Girls playable in Super Mario Bros X / SMBX