Two claims in these comments were stronger than the permutation runs
behind them. The WAV round trip catches sample-size against channels
and leaves frame-count against sample-rate entirely green — the crop
and the reformat are what catch that pair, and a reader who trusted the
round trip would drop exactly the wrong case. The font file listed what
it pins and never said that glyph-padding, offset-y and three of each
atlas rectangle's four fields are read by nothing here at all.
Two more permutations run and recorded while fixing it: GlyphInfo's
image moved to the front, which shifts the four ints 24 bytes and
collapses the glyph search, and Rectangle's x with width, which moves
"measure ABC" to 39 and confirms the advance-0 fallback is the only
thing reading a width out of the recs array.
Audio was written off as needing a device. That is true of Sound and
Music and false of Wave: copy, crop, reformat, export, load and decode
are all CPU work, and wave-format is the same scalars-in/fields-out
shape gen-image-color is, with the frame count computed rather than
handed over. Cropping to a single frame before decoding puts raylib's
byte-offset arithmetic in front of the decoder, which is what tells
sample-size from channels — an axis discriminator, not a mirror.
Fonts were said to have no headless test. They do, once the program
stops asking raylib for a font and builds one out of Flan arrays: text
measuring reads every field and computes. Both cases were verified red
by permuting the defstructs; the permutations are recorded in the
comments so the next reader need not rediscover which ones bite.