Not sure where this should go, so new topic.
http://www.wam.umd.edu/~darreon/nnn.smv
This movie demonstrates the glitch, but here's some useless jabber:
When mario holds a direction his speed is determined by some formula. The simple idea would be to have something like this:
if (holding right) {
speed = speed + 3
if (speed > 50) speed = 50
}
else if (on ground) speed = speed * 0.8
This is rather arbitrary, but Super Mario World does not use this formula, instead for the second equation it does something like this:
if (speed > 50) speed = speed - 5
Maybe this is done so that if you are moving really fast and you hold to the right you don't instantly lose your speed, who knows. What is important to note is that speed will then fluctuate if you hold right:
50 -> 48 -> 46 -> 49 -> 47 -> 50
Also important to note is that if you're not holding right, your speed is never effected. Therefore getting to max speed and not touching the direction pad is faster than holding right! How much faster? about 3%
A few other concerns. This only applies if you are not on the ground, but apparently touching the ground for 1 frame is like not touching it at all. The biggest downfall of all about this is that if you ever press a direction again, it will be like starting running from scratch. So once you start the trick you better finish the level without having to touch the ground for more than 1 frame, or gain so much time before you do have to touch the ground again that it is still faster.
JXQ seems to have also discovered part of this trick, that is taking advantage of flying speed while not flying. Its the same thing except instead of running until you are at full speed he flies. This is just as fast as flying but requires the cape to start it of course.
Sorry for not revealing this sooner. I wanted to remake the run of Super Mario World and surprise people, but as I started to make the run I kept getting very bad random fadeout time in iggy's castle (15 frames slower). I tried many times (that video is not the original remake I was working on, it was a quickly to get to iggy's castle), but eventually I just gave up. Then I moved and the computer the run was on was in storage. I would be happy if someone were to resume work and make this run.
This trick is really pretty minor. But on a game like this where in most cases there isn't much you can do except make sure you're running to the right the whole time it makes a huge difference compared to the fluctuations we are used to. I would bet that there are other games out there that use a similar formula to determine speed and that the same trick could be used on those games. Also note that the formula I gave is probably not the real formula the game uses, but it seems similar in all characteristics.
