TextWeight defines the various text weights, in order of increasing weight.
Note that if you leave this field unset, it will default to TextWeightThin. If you want the normal font weight, explicitly use the constant TextWeightNormal instead. TODO realign these?
type TextWeight int const ( TextWeightThin TextWeight = iota TextWeightUltraLight TextWeightLight
Family string Size float64 // as a text size, for instance 12 for a 12-point font Weight TextWeight Italic TextItalic Stretch TextStretch