Method GlyphBoxes

axis.go:309–348

GlyphBoxes returns the GlyphBoxes for the tick labels.

(p *Plot)

// GlyphBoxes returns the GlyphBoxes for the tick labels.
func (a horizontalAxis) GlyphBoxes(p *Plot) []GlyphBox {
	var (
		boxes []GlyphBox
		yoff  font.Length
	)

	if a.Label.Text != "" {
		x := a.Norm(p.X.Max)
		switch a.Label.Position {
		case draw.PosCenter:
			x = a.Norm(0.5 * (p.X.Max + p.X.Min))
		case draw.PosRight:
			x -= a.Norm(0.5 * a.Label.TextStyle.Width(a.Label.Text).Points()) // FIXME(sbinet): want data coordinates
		}
		descent := a.Label.TextStyle.FontExtents().Descent
		boxes = append(boxes, GlyphBox{
			X:         x,
			Rectangle: a.Label.TextStyle.Rectangle(a.Label.Text).Add(vg.Point{Y: yoff + descent}),
		})
		yoff += a.Label.TextStyle.Height(a.Label.Text)
		yoff += a.Label.Padding
	}

	var (
		marks   = a.Tick.Marker.Ticks(a.Min, a.Max)
		height  = tickLabelHeight(a.Tick.Label, marks)
		descent = a.Tick.Label.FontExtents().Descent
	)
	for _, t := range marks {
		if t.IsMinor() {
			continue
		}
		box := GlyphBox{
			X:         a.Norm(t.Value),
			Rectangle: a.Tick.Label.Rectangle(t.Label).Add(vg.Point{Y: yoff + height + descent}),
		}
		boxes = append(boxes, box)
	}
	return boxes
}

// A verticalAxis is drawn vertically up the left side of a plot.
type verticalAxis struct {