Search found 8731 matches

by rainwarrior
Mon Feb 20, 2012 12:18 pm
Forum: NESdev
Topic: Battletoads and graphics
Replies: 16
Views: 7236

For the battletoad character sprites, I did see that the game first writes code to RAM somewhere to efficiently copy sprites into CHR-RAM. You can see from watching CHR-RAM in an emulator that it only ever stores one frame of the battletoad, and uploads a new one as needed. Try tracing a few frames,...
by rainwarrior
Fri Feb 17, 2012 6:37 pm
Forum: NESdev
Topic: Sprite mulitplexing / raster effects?
Replies: 18
Views: 7553

Ahh, yeah he probably did mean that.
by rainwarrior
Fri Feb 17, 2012 6:01 pm
Forum: NESdev
Topic: Sprite mulitplexing / raster effects?
Replies: 18
Views: 7553

Dwedit wrote:It just means you'll get slightly different results from the ever-unreliable sprite collision flag that nobody should use anyway.
? There's like a zillion games that use it reliably.
by rainwarrior
Mon Feb 13, 2012 12:24 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

Yeah, I had a few ideas about how to adapt it, but I figured someone must have worked out a decent method for it already. Thanks for finding that.
by rainwarrior
Sun Feb 12, 2012 11:54 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

I said "general purpose". I'm not trying to compress anything, I'm just wondering what kind of data (if any) this algorithm can't apply to. If your data doesn't have unused symbols, is there a viable variant of the algorithm? (Or would it become complex enough that there are better compres...
by rainwarrior
Sun Feb 12, 2012 8:18 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

Well, 1994 is the earliest cited example; why would I assume there's something earlier unless someone tells me there is? I tried a quick search of Romhacking.NET but all I'm finding is that people are commonly hacking an implementation of DTE into old ROMs to make themselves more room to translate i...
by rainwarrior
Sun Feb 12, 2012 7:43 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

byuu, if all of your symbols had equal probability (worst case for huffman) the resulting huffman tree would be the same as fixed-bit-length (though storing the tree itself will put you over by the size of the tree). Best case for huffman I guess would be all the same symbol, which could be represen...
by rainwarrior
Sun Feb 12, 2012 2:06 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

So I got bored and made a graph of the Huffman tree:
http://rainwarrior.ca/projects/nes/batt ... uffman.png
by rainwarrior
Sat Feb 11, 2012 10:15 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

Yes, there was a Japanese version, but it was developed in Britain. I doubt the decision to use huffman had anything to do with it being theoretically good for Japanese text. They had one 32k bank dedicated to cutscenes, and they managed to squeeze an extra 4k out of it, so... why not? There's very ...
by rainwarrior
Sat Feb 11, 2012 8:37 pm
Forum: Homebrew Projects
Topic: First NES game (Mineshaft)
Replies: 42
Views: 37678

This is pretty good! I had fun.
by rainwarrior
Sat Feb 11, 2012 6:06 pm
Forum: NESdev
Topic: Battletoads text decompression (huffman)
Replies: 16
Views: 35081

Battletoads text decompression (huffman)

I've been playing a lot of Battletoads lately, and I was surprised to realize that every level introduction has several different texts, chosen from at random. I was impressed by how often I was seeing new text. So, I thought it would be fun to dump the text out of the ROM. At first I tried a straig...
by rainwarrior
Wed Feb 08, 2012 11:59 am
Forum: NESdev
Topic: Non-native english coders : In which language do you comment
Replies: 24
Views: 6777

English is my native language, but I've always been impressed that so many non-native-English coders make the effort to leave English comments. I don't expect/demand it, but I do appreciate it. (Non-English comments I attempt to translate if I need to; at least the internet has made rough translatio...
by rainwarrior
Tue Feb 07, 2012 1:41 pm
Forum: NESdev
Topic: Fun with Lisp: Programming the NES
Replies: 7
Views: 3453

Intriguing.
by rainwarrior
Sun Feb 05, 2012 3:25 pm
Forum: NESdev
Topic: Rad Racer scrolling
Replies: 16
Views: 27052

Rad Racer scrolling

I went and traced through Rad Racer to get an idea of how it does its rendering. I thought it was quite interesting, so I wanted to share what I found. So, the NMI looks like this: > The frame begins with horizontal mirroring set (done in previous frame). > Scrolling is set for the sky's parallax. >...
by rainwarrior
Sun Feb 05, 2012 12:21 pm
Forum: NESdev
Topic: VRC6 scanlines and scrolling
Replies: 21
Views: 8020

I always thought it was kinda cool that the background was reacting to the gameplay. Like it was a living brain or something that didn't like it when you were fighting.