mdb.classicgaming.gamespy.com — These kinds of things always fascinated me. This is the technical explanation of how "rooms" and level design actually work in the NES Metroid cart. It is amazing to see how the developers made a massive world (for its time) with such limited capacity and design capability. Many NES games follow the same "room" data design.
Dec 1, 2006 View in Crawl 4
aubreyDec 1, 2006
Wow! The "world map in 1024 bytes" picture + the explanation that each time Samus goes through a door the game switches to the opposite scroll type totally explains what you see when you explore 'new' areas with the door glitch trick.I spent so many hours trying to find new places to go and explore using that glitch. Not once did I realize I was just exploring some other part of the map that I had already been to. The doors that floated in the air in the glitched areas were probably the result of the scrolling issue this person mentioned about.Very cool
robotsuDec 1, 2006
daridave:It's not just about tile collision, it's about the amount of space available in the NES RAM for graphics. NES CHR RAM (more or less graphic ram) is 8k, and even with compression and bankswapping it never feels like enough.
marnaqDec 1, 2006
Now THIS is programming.
namcoDec 1, 2006
It was always sweet to be in the other hidden room, and actually get through a door and see the game scroll up, then over. But usually when I was exploring, I ended up in lava with no hope of getting out.I also thought it was cool when you were on levels with several rows of horizontal halls, and you "walldoored" up to the above hallway, the scrolling would be screwed up and the screen wouldn't be locked to the room anymore until you went through a door.This article answers a lot of cool questions for me :)
delmonteDec 2, 2006
Here's my crazy theory about Metroid: (Sorry long post, but bear with me, it's interesting)In Japan, the game was on a double-sided Famicom Disk. There are 5 "sub-worlds" in the game, each with its own set of room designs, graphic tiles, music etc. On the FDS (Famicom Disk System), there are 3 worlds on one side of the disk, and 2 on the other. Taking some elevators in the FDS version will require you to flip the disk side.Metroid was seemingly first made as one of the last FDS game, showing it's ability to have bigger worlds than a NES cart games which were only going up to 64k (and a double-side FDS game was 128k), and the ability to save your game progress on the disk.But somewhere along the way, ROM chip prices dropped enough, and Nintendo found a way to put a bank-switching chip in a NES cart, bringing the total size to 128k. So Metroid was to be the first 128k NES cart game, and because of the lack of writable media, the first to use a password system.You can see that the game was designed with both the FDS and NES cart version in mind. Each of the 5 sub-world happen to fit perfectly on a 16k ROM chip. The first NES bank-switching chip used in Metroid (MMC 1) couldn't do live switching, and induced some little delay when switching from a bank to the other. That's why the switching happens in the elevator shaft, when it's not that bad to see the screen flicker as it switches banks.So, you could say that in the NES version of Metroid, Samus travels from chip to chip using the elevator. The 1024 bytes global room map is in a bank that is always loaded and shared by all of the sub-worlds, so that makes the "secret rooms" glitch possible. If you get to a room of another sub-world without taking the elevator, it will be displayed with the room design and graphics of the current world.That leads me to the crazy part of my theory. The names and scenario in Metroid weren't translated by Nintendo of America, but rather by the Japanese team (probably by Hirokazu Hip Tanaka, the music composer, who named the sub-worlds, and speaks english).Metroid is the name of the "ROM Edition" of this Japanese FDS game that wasn't called Metroid there. So where does the name Metroid come? If you rearrange the letters from Metroid, you can make: ROM EDIT... Coincidence?Sure it may also have something to do with Metropolis (the movie) and Android... (Metropolis featured a female android). But I think these references are the reasons why they kept Metroid instead of Treomid or another name, as it just fits too well.And then, there are references to Alien, the movie, but that's another story in itself.
simpleprimateDec 17, 2006
@ daridaveDugg ^ for reference to Dragon Warrior! =P