Search found 81 matches

by eteream
Tue Apr 06, 2010 12:59 am
Forum: Video Display Processor
Topic: Understanding the VDP's scrolling capabilities.
Replies: 67
Views: 75644

With SNES you have up to 16 DMA's chanenles avaliable, so in practice you cann't do what genesis does. You need to spend all the displaying time (in contrast with vertical retrace time) updating scroll values if you want more than 16 scroll. In the other side, it wastes more memory on MD. Wrong. A ...
by eteream
Thu Apr 01, 2010 3:07 pm
Forum: Video Display Processor
Topic: Understanding the VDP's scrolling capabilities.
Replies: 67
Views: 75644

This implies a minimum of four planes that might be placed above one another by a skilled game designer. This would be significant, as the Genesis is known to have produced more than eight independently scrolling backgrounds, called "fake" parallax by those who do not consider the effect significan...
by eteream
Wed Mar 31, 2010 3:45 pm
Forum: Hardware
Topic: How sonic 3 save feature works?
Replies: 14
Views: 17758

OK I understand. Thanks! Some time ago I read a paper of saturn or segaCD (I don't remember) where it said how to do things like this, where there are several solutions for a case between hardware and software. The idea was to be backwards compatible. Doing things only in one way you can save, eithe...
by eteream
Tue Mar 30, 2010 5:10 pm
Forum: Hardware
Topic: How sonic 3 save feature works?
Replies: 14
Views: 17758

Where resides the hardware to change the logic of the 2-4MB area, on the machine or in the cart board? For a common model... I mean, where is located physically register 0xA130F1 in the MD or in the cartridge? Which game was it? Some games use their own custom hardware rather than SEGA's "standard"....
by eteream
Sat Mar 27, 2010 9:06 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

... Please share water movement effect routine. You guys talk about such Amazing stuff but when are you going to share some code. Eteream please take time to make some tutorials. It is so frustrating seeing people talk about these great routines but no one is showing me how it's done. Well, as I sa...
by eteream
Sat Mar 27, 2010 8:42 pm
Forum: Hardware
Topic: How sonic 3 save feature works?
Replies: 14
Views: 17758

OK, thanks! May be timing is different bcose I put another rom into a sonic 3 board and don't work. the other rom has a common parallel save feature.

I discovered how to desolder in the easy way, so I can make some tests.

And may be I will try to make a Sonic & Knuckles 3 in one cart only...
by eteream
Wed Mar 24, 2010 12:08 am
Forum: Hardware
Topic: How sonic 3 save feature works?
Replies: 14
Views: 17758

That works with and without Sonic & Knuckles cart?
by eteream
Tue Mar 23, 2010 11:11 pm
Forum: Hardware
Topic: How sonic 3 save feature works?
Replies: 14
Views: 17758

How sonic 3 save feature works?

If I do not go wrong, normally, games take advantage of the 2 higher megabytes for saving feature. This is how does it work in sonic 3? Is it a serial or parallel memory? (I have read both!) But then, how does it work when connected to the Knuckles cartridge? Knuckles cart maps sonic 3 to 2-4MB spac...
by eteream
Sun Mar 21, 2010 11:33 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

For "task" I understand some kind of procedure with his own stack, 'memory map' and register set, and with some kind of task schedule. May be "interrupt procedure" is enough. One for debug proposes (zero division,...), one for VINT, one for RESET, and one for IDLE or non-VINT code. I don't have a ti...
by eteream
Fri Mar 19, 2010 1:35 am
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

Yes, I was wrong: definitely you can work with compresed map-data in active game. For one direction scroll game simply keep decompressing when you need it. For multiple direction scroll make 'zones' as TmEE said. Only one account, when screen scrolls it takes more CPU than when not. In commercial ga...
by eteream
Thu Mar 18, 2010 3:30 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

TmEE, what type of game is? (platformer, beat'm up,...)
How many scrolls have? (1,2,... 1 direction, both directions,...)
by eteream
Tue Mar 16, 2010 5:38 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

Regarding reprogramming - challenge is everything! :D To have large, interesting levels, you also need to reprogram the maps quite frequently and fast, usually involving decompression of some sort. This is a challenge, especially if a game is a fast scroller. If it doesn-t involve decompresion, I t...
by eteream
Sat Mar 13, 2010 2:48 pm
Forum: Demos
Topic: Game release, Uwol - Quest For Money
Replies: 36
Views: 42069

That rocks! how to do a great game with near to nothing in-game graphics.

I feel a strange feeling when it says "press button" but start button don't work... for several games is only used is in title screen.
by eteream
Wed Mar 10, 2010 3:56 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

>>Each moveable independent 'thing' should be a sprite since planes are a whole thing. So all dependent drawings go to a plane. 'Independent on Plane A ... Dependent on Plane B ... Ok! No. You have: - Two big pictures named planeA and planeB* (and may be window too), usually used to draw background...
by eteream
Mon Mar 08, 2010 5:25 pm
Forum: Megadrive/Genesis
Topic: Advice on the Art of Genesis level Building
Replies: 30
Views: 19270

Each sprite/tile is mapped to one of the 4 palettes, so each tile can have up to 15 colors (or 16 if you care transparent one*), and each sprite up to 15 colors. *The deeper background can use the background color as own color. When working with backgrounds the limit are the tiles, so I recommend to...