Upgrade saved drawings to the current document shape. Accepts a 1.9.x
Drawing[] or a DrawingsDocument of any version. Every field is
validated, the 1.9.x text keys are lifted out of the style bag into text,
bare level ratios become coloured levels, and array order is kept. An entry
that could never be rendered is dropped; anything unparseable yields an
empty document rather than an error. The result is version 3 when a drawing
carries an interval range and version 2 otherwise.
Upgrade saved drawings to the current document shape. Accepts a 1.9.x
Drawing[]or a DrawingsDocument of any version. Every field is validated, the 1.9.x text keys are lifted out of the style bag intotext, bare level ratios become coloured levels, and array order is kept. An entry that could never be rendered is dropped; anything unparseable yields an empty document rather than an error. The result is version 3 when a drawing carries an interval range and version 2 otherwise.