AtariAge Forums: EricBall - Viewing Profile

kamakazi, on Mon Feb 22, 2010 2:23 AM, said:

A game is made up of main two types of code - code which is responsible for getting stuff displayed, and code which is more display independent. (There's also code which does other I/O like user input and sound, but that's typically a much smaller piece.) You'd think it should be possible to somehow swap out the display dependent code, but unless the game was written with that in mind, you will probably find even the "display independent" code is structured to make the "display dependent" code as easy as possible. This might be something as simple as whether the GPU can reflect a sprite or whether Y=0 is the top or the bottom of the screen, but can be as challenging as bitmap versus tilemap backgrounds.

Additionally, trying to reuse code for porting without the original commented source code will be much more difficult. Not only will you have to create a reasonable disassembly, but you will need to reverse-engineer the context of each piece of code.

kamakazi, on Mon Feb 15, 2010 10:07 AM, said:

Nope. With that you just need time and desire to start working. Graphics tools might help once you get beyond the "get something one the screen" phase and into the "make it look pretty" phase. However, you may find it just as easy creating sprites by hand rather than trying to use tools which don't speak 7800.

kamakazi, on Mon Feb 15, 2010 10:07 AM, said:

Maybe. I don't know if anyone else has gone that route. It might be easier or hard than the DASM+emulator route.

kamakazi, on Mon Feb 15, 2010 10:07 AM, said:

The advantage of the 2600 over the 7800 is it's easy on the 2600 to get something on the screen. 3 lines of VSYNC+VBLANK and 262 lines of playing with TIA registers. While the 7800 you have to set up your display lists and your DLLs and then hope you didn't forget something or you're staring at a blank screen wondering what you did wrong. The nice thing about the 7800 is once you get that working most of the programming is data movement and AI, while on the 2600 you get into display kernel programming trying to update those TIA registers ahead of the beam.

kamakazi, on Mon Feb 15, 2010 10:07 AM, said:

Ask. There are people on the forum with the right hardware (i.e. CC2) to help out.

mos6507, on Fri Nov 6, 2009 10:59 AM, said:

Skeleton had that problem. I wasn't very receptive to feedback and was blinded to the "purity of my vision". I think Skeleton+ is more what Skeleton could have been if I had listened.

And although johnnywc gives some excellent reasons to do a port, I think there are some significant downsides to ports:
1. Copyright & Trademarks. Although they may be old and possibly even forgotten, you really don't want to have your creation taken away from you because you're infringing on someone else's IP.
2. Although the 2600 has been pushed far beyond Pong & Combat, it still has limits. An original game can be reworked to fit what the 2600 can do, while a port will either die or suffer greatly in the translation.

I do not have a PSP, although I do have a PS3 and a DSlite.

From what I've read, the PSP Go is a step backwards from the PSP w/UMD. About the only advantage of the PSP Go over the PSP is the smaller size (when closed). But the disadvantages are numerous:

• no older / used / rental games
  
• smaller screen
  
• more expensive (smaller) flash memory
  
• unknown durability of slide-out controls
  
• smaller form factor may be less comfortable
  
• various roll-out screwups

And the PSP w/UMD is capable of downloading games, just like the PSP Go. So if you've been putting off buying a PSP, I'd recommend scooping up a PSP w/UMD before they're gone.

lucifershalo, on Sun Oct 4, 2009 5:53 PM, said:

It depends on how easily the code can be modified to meet your requirements and how willing you are to compromise your dreams. Think of it this way - at one end of a line is Dig Dug unmodified; at the other end is your dream. To move one end requires effort; the other end requires sacrifice.

The disassembly is probably a good place to start. That will give you a base to start modifying. At some point you may decide "you can't get there from here" and start from scratch. But the experience of modifying the base won't be wasted. You will better understand what you need to create in order to meet your dream. And you still may be able to use some parts of the original you modified.