Shift encoding strategy

[dy]

Values are chosen to be direct positive values from 0-100 range from U+0100 unicode range. No negatives. What would be the right approach to shift? Factors:

• align: center feature may require negative shift
• editing not affect parts outside of selected fragment
• zoom levels - should clutter text with multiple shift symbols

0. Absolute shift

• Just a bit unusual in editing, since requires guaranteed 1 extra operation per sample, worse than 1. on large scale since relative offset reduces shifts to minimum

1. Cursive + 1 up/down

• Natural flow (only up/down is needed),
• reduces number of characters in a font (only up/down needed)
• reduces number of characters in textarea (no need to provide each character level)
• removes clipping limit - waveform can go as high/low as required.

• editing combinings is a bit unusual - cutting a character removes shift of the following character and all subsequents baseline shift.
• separate up/down character is better than combinings: it makes step "up" by typing it (muscular logic). It can also be visualized as thin connection line. But still redundant and a bit unexpected direction change in editing, 0-width space eats away one..n caret shifts
• Relative positioning creates a lot of noise on small scales when there's too much vertical variation, like 9,0,9,0,9,0. Absolute values are guaranteed to limit to one extra character overhead.

2. Cursive + n up/down

A mix of 0. and 1.: relative offsets to any amount.

• Removes small scale clutter, reducing number of shifts to 1

• still has critical baseline shift drawback
• requires 2x shifting characters: up 100, down 100

2.1 Cursive with copy-paste compensation

• can fix critical baseline shift

3. A separate font for sample values

Since bars are almost always 0-aligned, with little decorative shifts up/down, that hardly affects baseline shift (can be handled on copy/paste events); and samples data doesn't need full bar value, but rather single point with nice shift ability, mb there's a sense switching from bars font to samples font for small-scale cases.

That samples font would be just timedata font with features:

• use any symbol/character
• shift subsequent absolute markers (combining?) or mb provide shifted characters already for better editing
• no need for center-align => no need for negative shifts/values
• it can be even be a linear-data font, connecting chars with proper lines _/ˉ_/ˉ
• width, weight variables

Originally posted by @dy in https://github.com/audio-lab/wavefont/issues/18#issuecomment-780170992