Set the synthetic font-weight contour offset (in font design units) of one run of data.
This mutates live text data, like a setter on a material: the run is repacked and
regrouped before the call returns, so it is valid at any point in the TextData's life —
including after it is already bound and rendering. Runs are packed synchronously by
createTextData / createDefaultTextData / updateTextData, which is why the offset
belongs to the owning data rather than to a detached run descriptor.
Positive offsets expand the rendered fill outward (bolder / thicker).
Zero removes any previously set offset, returning the run to the base pipeline.
Offsets are keyed by run identity, so an update that replaces a run descriptor (e.g.
updateDefaultTextData, or updateTextData({ update: "replaceRun" })) drops the offset;
re-apply it to the new run — by index, most conveniently.
Set the synthetic font-weight contour offset (in font design units) of one run of
data.This mutates live text data, like a setter on a material: the run is repacked and regrouped before the call returns, so it is valid at any point in the
TextData's life — including after it is already bound and rendering. Runs are packed synchronously bycreateTextData/createDefaultTextData/updateTextData, which is why the offset belongs to the owning data rather than to a detached run descriptor.Offsets are keyed by run identity, so an update that replaces a run descriptor (e.g.
updateDefaultTextData, orupdateTextData({ update: "replaceRun" })) drops the offset; re-apply it to the new run — by index, most conveniently.