Submitted By: ancsikDate: June 13, 2011, 11:55:08 AM
Summary: General guidelines when making charts - they can be bent/broken sometimes, but it needs to make stylistic sense when you do.
This is a work in progress, I'll keep adding to it as I have a chance. Don't make any changes until I'm done and open it up to everyone.
The beat should be red:
The beat falls on quarter notes (in 4:4 time, at least - but almost any song that you'd want to write a file for will be in 4:4) by definition. Songs can deemphasize the main beat at times (usually falling back on the down beat) and the dominant melodies may deviate in all kinds of ways, but there's usually some main element of the song (a drum or bass synth) tapping away at a nearly constant pace. This means that the correct BPM and offset is the one that lines up the red notes with that beat.
It will still sync correctly if the offset makes the beat fall on blue notes. It will sync correctly if the beat and downbeat (usually a quieter, softer drum / bass synth, may or may not be constant - though there are exceptions, like the prominence of a heavy backbeat in rock drumming) are red because you doubled the BPM. However, it will always make more sense to play and to write if the beat is red, the downbeat is blue, and everything lines up accordingly.
Syncing can be very hard sometimes, it shouldn't be most of the time
MixMeister is a free BPM analyzer. It can't handle variable BPM songs and it can be wrong (especially if sections of the song are particularly quiet/loud compared to the rest), but it's usually at least close, if not dead on.
For a constant BPM song (or one that uses direct multiple speed changes - for example, an 80 BPM slowdown when the rest of the song is 160), use a BPM analyzer to get a baseline estimate of the BPM, then throw down 15-20 measures of quarter or eighth note left-right arrows from the start of the song and a couple measures worth near the end of the song, then throw the chart on dark and autosync, then tap along with the beat (rather than the arrows) through those notes a few times and see if autosync settles on a constant value or keeps shifting around. If the offset is constant and even the few measures late in the song are synced, then you've synced the chart, if not, adjust the BPM slightly (by less than .100) and try again. Stepmania SSC (SM 5) has an enhanced autosync mode which calculates a new BPM and offset simultaneously, but doesn't apply them until you quit playing (unlike normal autosync which does), which might be helpful if you're close but not quite sure where to go. If the chart is going to have a half-BPM slowdown or any other simple multiple BPM changes, see the next section for the easiest way to do it.
For a truly variable BPM song, you've got your work cut out for you, but, in theory, it's a matter of identifying where the BPM changes are and treating each new section as a separate constant BPM "song". You might even want to go as far as using Audacity (also free) and chopping the song into sections so you can calculate each BPM separately, then go back to the full song and add the changes where they need to go.
Write the steps before adding the gimmicks
If you're using SSC (SM 5), then half/double BPM sections, stuttering, pauses, etc. can easily be added after putting down the steps using some commands in the Enter menu - steps will be shifted around correctly to maintain the original rhythms afterward. This means you can plan out the patterns and rhythms to make sure everything feels right, then apply the desired effects after you know the chart is written well, rather than having to deal with both concerns simultaneously.
Avoid blue fever: make the arrow colors mean something
Pauses, double/half BPM sections, stuttering, etc., can be written in ways that force the beat onto non-red notes afterward. Unless you mean to make a chart so gimmicky that the colors never mean anything, this is undesirable and can make a chart very awkward to play. It can take some trial and error with pauses or the exact timing of the BPM changes if the boundaries of a half-speed section don't line up on the beat, but it's worth it to make everything fit correctly. That said, it's probably not worth the fight if whatever causes the problem is only two steps from the end of the chart, but it half the chart is off, there's definitely a problem.
Write patterns that follow the feel of the song
A well written chart necessarily follows the rhythm well, but you get to pick from competing rhythms in many cases and - just as importantly - the actual patterns should make sense in conjunction with the song. For example, a short, soft, quiet section in the middle of a song probably doesn't warrant every step being a jump. Most importantly, the "feel" of the song is purely subjective, so just make sure to do what feels most appropriate to you - going through a rough draft and adding tons of jumps and hands to make it "hard for the sake of being hard" means you're probably forcing unnatural patterns into the chart, but if a chart just ends up being that hard as you write it, then there's probably a reason for it.