Is it possible to manipulate the character of a game ?

[Infa Red]

Just theorizing here. Something that would only be tried on home bench, not for sale, no copyright issues, etc.. Just a guy playing around.

So, to my understanding, the character of games (lets use Mario Bros for example for now) is a "Sprite" correct ? Meaning this isn't drawn by the monitor the same as the rest of the graphics correct ? Its like already all made on a chip right ? (or something like that?).

My theory would ask this: Is it possible to find the chip that contains said character "sprite", then overwrite that sprite with your own homemade/unique sprite ? In turn, as long as you made this sprite the exact same size, nothing should go wrong or look any different (other than the character change of course) right ?

 

[ChewbaccaBox]

uh
to your last question, yes. there were tons of rom hacks bitd that changed the graphics.
look at pacman for example.

Pac-Man/Bootlegs

Due to the tremendous popularity of Pac-Man in the arcades, and the arcade operators' insatiable appetite to cash in on the craze, bootleg arcade manufacturers produced...

strategywiki.org

you see a lot of bootlegs just change graphics or the maze
pacman hearts changes the dots into hearts.
there's also newer hacks like 'vector pacman' that makes pacman look like a vector game.

but everything is drawn on the monitor exactly the same as anything else. a raster picture is a raster picture.
you're thinking of the game board, which handles sprites differently to other parts of the game, and combines the sprites and background and stuff into a raster picture to send to the monitor.

the chips that store the sprites are the same that store the data for the rest of the game. they're the EPROMs. aka the larger chips with stickers on top. they contain the ROM data of a game.

you'd have to program a new eprom, it would be wise to edit the rom on a computer first and try in mame before you think about burning it to a rom and test it in pcb.

there was a popular DOS program BITD called Turaco that let you edit the sprites of some games.
but sprites are stored in different ways and in different places in every game.

so for a game like pacman or on pacman hardware, it'll be easier, since lots of people have done it.
but for a more niche and proprietary hardware type game, you'll have to do more work yourself.

 

[SCUBA King]

Yes, 100% what @ChewbaccaBox said^^

 

[Infa Red]

Got it - Thanks @ChewbaccaBox ! So I was wrong on some details, but ultimately right on the concept of it being possible, and they way it is possible. This is cool ! And its funny all at same time. We could do some real hilarious stuff if you think about it.

it would be wise to edit the rom on a computer first and try in mame before you think about burning it to a rom and test it in pcb.

Very wise ! Good idea.

 

[clewis]

Look up NES CHR Editor.

 

[thegleek]

$34.99 - https://smile.amazon.com/dp/1075952727/

 

[mgkastra]

uh
to your last question, yes. there were tons of rom hacks bitd that changed the graphics.
look at pacman for example.

Pac-Man/Bootlegs

Due to the tremendous popularity of Pac-Man in the arcades, and the arcade operators' insatiable appetite to cash in on the craze, bootleg arcade manufacturers produced...

strategywiki.org

you see a lot of bootlegs just change graphics or the maze
pacman hearts changes the dots into hearts.
there's also newer hacks like 'vector pacman' that makes pacman look like a vector game.

but everything is drawn on the monitor exactly the same as anything else. a raster picture is a raster picture.
you're thinking of the game board, which handles sprites differently to other parts of the game, and combines the sprites and background and stuff into a raster picture to send to the monitor.

the chips that store the sprites are the same that store the data for the rest of the game. they're the EPROMs. aka the larger chips with stickers on top. they contain the ROM data of a game.

you'd have to program a new eprom, it would be wise to edit the rom on a computer first and try in mame before you think about burning it to a rom and test it in pcb.

there was a popular DOS program BITD called Turaco that let you edit the sprites of some games.
but sprites are stored in different ways and in different places in every game.

so for a game like pacman or on pacman hardware, it'll be easier, since lots of people have done it.
but for a more niche and proprietary hardware type game, you'll have to do more work yourself.

With the mention of sprites, might be talking about frame split, having the sprite on a frame by themselves, and then have the background and other elements flash and it iterates between the two.

 

[english2]

https://forums.arcade-museum.com/threads/turaco-sprite-editor-for-windows.557530/