makeFromPosH
Returns a TextBlob built from a single run of text with x-positions and a single y value. Returns null if glyphs is empty.
Return
new TextBlob or null
Parameters
glyphs
glyphs drawn
xpos
array of x-positions, must contain values for all of the glyphs.
ypos
shared y-position for each glyph, to be paired with each xpos.
font
Font used for this run