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Author Topic: NES Sprite Hacking guide?  (Read 799 times)

jayjay300

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NES Sprite Hacking guide?
« on: June 27, 2020, 01:52:12 pm »
Hello!  Sorry for the probably simple question but-- this is the newcomers board!
So I've been learning about ROM hacking and had a great idea for a hack, and would hate to abandoned due to difficulty. Hacking the text, and the palette, had no issues.

However, using Tile Layer Pro, the sprites are extremely scrambled, making it very hard to lay out to edit. A few things like the title sequence are easy to pick out, but the rest there is barely any organization. Are there any tricks to make this easier? For example, in the PPU viewer in my emulator, I can get the assembly locations of the sprites at least on the screen currently. Any way to use this information to locate them more easily in a sprite editor? Any help or tricks to sprite editing would be MUCH appreciated! I know this is just how some games are, as I've done sprite editing in other games and systems with little difficulty. Just looking for ways to do it for some of the more difficult games. For reference in case anyone wants to look, I am using the Gulligan's Island game for NES. Thanks in advance for your help! :cookie:

Cyneprepou4uk

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Re: NES Sprite Hacking guide?
« Reply #1 on: June 28, 2020, 05:50:01 am »
If you have figured out that one can use ppu viewer + code/data logger in fceux, I don't really know how can you make your life even easier. Using a correct palette in a tile editor maybe?

Not sure if it will be easier in your case, but you can dump ppu memory from emulator's hex editor into binary file, then open it in your tile editor. So you basically dumping only those tile banks that you actually need, then edit them and paste back into rom.
iromhacker.ru - NES ROM hacking tutorials for beginners. Please use Google Translate browser extension

PhyChris

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Re: NES Sprite Hacking guide?
« Reply #2 on: July 04, 2020, 03:35:17 pm »
fellow newbee here. I can vaguely remember NESticle having a built-in editor of some sort that made sprite editing more convenient.
I can remember using it to edit double dragon 2 sprites to look like ninjas. 

Edit: I'm old   
« Last Edit: July 04, 2020, 03:53:59 pm by PhyChris »

Celice

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Re: NES Sprite Hacking guide?
« Reply #3 on: July 04, 2020, 10:58:11 pm »
The graphic editor YY-CHR lets you rearrange how you view tiles in the ROM. There are several presets and one of these might be useful for you. If they aren't, you can even map your own custom tile arrangements to view the data in the ROM with.

For example, normal viewing in YY-CHR



And then changing the pattern viewer to another preset (bottom left drop down menu)

Bregalad

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Re: NES Sprite Hacking guide?
« Reply #4 on: July 05, 2020, 05:48:17 am »
What you're asking is exactly the same as editing music - perfectly possible but it will be game-specific, or at the very least developer-spectific.

Similar to how each developer craft their own sound engine to replay music, and often re-use it among its games, they will develop their metasprite engine and re-use it among games.

Tile editors can edit the sprites themsevles, but for the NES they're either 8x8 pieces or 8x16 pieces, and what you want is to know how the game puts those small pieces together to form a metasprite. The only way is ASM hacking and understanding how the engine works. Without it you can only hack the graphics themselves, which is limitating.