Graphics hacking. Where to start?

[Inky]

In the past, I have messed with Hack-o-matic and putzed around with the graphics on a couple 2600 games. I see a few things I'd like to change around with some 7800 games, but not sure how to start with this. Any ideas?

[EricBall]

Graphics on the 7800 is very different from the 2600, so you're going to need different tools. (Which might exist, who knows?)

 

First, graphics data is laid out "upside down" with the last scanline on the lowest address and each scanline on a separate page. e.g. for a 2 byte x 16 line sprite

$e000-$e001 bottom line

$e100-$e101 2nd last line

...

$ee00-$ee01 2nd line

$ef00-$ef01 top line

(Sprites are typically 16 or 8 lines high and will be on even 4K (16 line) or even 2K (8 line) address blocks.

Second, while sprites on the 2600 are 1 bit per pixel, sprites on the 7800 may be 1, 2 (most common), or 4 bits per pixel depending upon the graphics "mode". The bits from the graphics data are combined with bits in the display list entry to determine if the pixel is transparent or the output color (from a 24 of 256 entry palette).

[PacManPlus]

This reminds me of something I am supposed to be working on...

[Dauber]

This reminds me of something I am supposed to be working on...

:-o :-o :-o :-o :-o :-o :-o :-o :-o

[+Defender_2600]

This reminds me of something I am supposed to be working on...

 

:love: !!

[PacManPlus]

lol - you guys are too funny. Thanks for the vote of confidence. It's actually 7800 development-related, not a game.

 

@Inky - sorry for the de-rail.

 

Only the 320A mode games (i.e. Frenzy, RipOff, etc.) would work with Hack-O-Matic (they would still be upside-down though).

I used to use something called "Tile Molester" for the 160A mode games (i.e. the most common mode), but it uses Java (which I hate) and it is a *pain* to set up.

 

One thing to note, however - Ms. Pac-Man (the original 7800 version) is the only one that has the graphics stored differently than every other game. They are not in the page format as Eric described, but the graphics are stored 'vertically' - 8 bits wide but 2bpp (2 bytes per scanline) then moves down to the next scanline. It has to do with the way they display list kernel is made.

 

Bob

Edited May 11, 2016 by PacManPlus

[DracIsBack]

lol - you guys are too funny. Thanks for the vote of confidence. It's actually 7800 development-related.

 

@Inky - sorry for the de-rail.

 

I hope you REZOLVE it. :-)

[+Atarius Maximus]

If you'd like to make changes to Pac-Man or Scramble, Jeff Wierer made specific graphics editors just for those two games. You can find them here and here.

[Inky]

If you'd like to make changes to Pac-Man or Scramble, Jeff Wierer made specific graphics editors just for those two games. You can find them here and here.

 

 

I just came across the scramble editor. I may play with that one.

 

Specifically I'd like to try my hand at cleaning up the graphics in Scrapyard Dog, and changing your character in Xenophobe to be more like Dr. Kwak.

[Jinks]

lol - you guys are too funny. Thanks for the vote of confidence. It's actually 7800 development-related, not a game.

 

 

Bob

Did anyone else here the sound of the guy going off the cliff on the cliffhanger price it right game in their head after reading this??

 

Hi Bob!! Found you!!

[PacManPlus]

Hi Bob!! Found you!!

 

Was I lost?

 

[Jinks]

 

Was I lost?

 

Lost without the seventy-eight-hundred.

Could be a country song?

[gambler172]

 

 

I just came across the scramble editor. I may play with that one.

 

Specifically I'd like to try my hand at cleaning up the graphics in Scrapyard Dog, and changing your character in Xenophobe to be more like Dr. Kwak.

I just came across the scramble editor. I may play with that one.

Specifically I'd like to try my hand at cleaning up the graphics in Scrapyard Dog, and changing your character in Xenophobe to be more like Dr. Kwak.

I made a Mario hack and used

Scrapyard Dog for it.I never released it.

Reason is,that I cannot test all changes

cause Scrapyard Dog is damn heavy to play.

I used Tilemolester.....only thing..I cannot

find is this damn SELLER graphics....all

other graphics,I was able to find.So if there

is somebody,who could help with the SELLER

screen.....

greetings Walter

Edited May 14, 2016 by gambler172

[Mord]

I made a Mario hack and used

Scrapyard Dog for it.I never released it.

Reason is,that I cannot test all changes

cause Scrapyard Dog is damn heavy to play.

I used Tilemolester.....only thing..I cannot

find is this damn SELLER graphics....all

other graphics,I was able to find.So if there

is somebody,who could help with the SELLER

screen.....

greetings Walter

 

I wouldn't be surprised if the seller graphic was the same graphic used for the silly puzzle at the end of the game.

[gambler172]

I wouldn't be surprised if the seller graphic was the same graphic used for the silly puzzle at the end of the game.

Yep....I found the silly Puzzle....but not the Seller screen