Method charPos

core/textfield.go:1252–1259

charPos returns the relative starting position of the given rune, in the overall RenderAll of all the text. These positions can be out of visible range: see CharRenderPos

(idx int)

// in the overall RenderAll of all the text.
// These positions can be out of visible range: see CharRenderPos
func (tf *TextField) charPos(idx int) math32.Vector2 {
	if idx <= 0 || len(tf.renderAll.Spans) == 0 {
		return math32.Vector2{}
	}
	pos, _, _, _ := tf.renderAll.RuneRelPos(idx)
	pos.Y -= tf.renderAll.Spans[0].RelPos.Y
	return pos
}

// relCharPos returns the text width in dots between the two text string
// positions (ed is exclusive -- +1 beyond actual char).