Only the coordinates get transposed -- the bitmaps apparently don't.
And all the prose amounts to "if the transposed bit is set, swap
instance s and t coordinates before painting", as far as I can tell.
Makes pages 3/4 and 7/8 in 0001346.pdf render. (But here the feature
isn't used to render transposed text -- it just has stripes that keep s
roughy constant, which would normally produce vertical runs but here
produces regular horizontal runs. It's not clear to me why this feature
is used for these pages!)
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