Method DrawGlyphBoxes

plot.go:197–253

DrawGlyphBoxes draws red outlines around the plot's GlyphBoxes. This is intended for debugging.

(c draw.Canvas)

// DrawGlyphBoxes draws red outlines around the plot's
// GlyphBoxes.  This is intended for debugging.
func (p *Plot) DrawGlyphBoxes(c draw.Canvas) {
	dac := p.DataCanvas(c)
	sty := draw.LineStyle{
		Color: color.RGBA{R: 255, A: 255},
		Width: vg.Points(0.5),
	}

	drawBox := func(c draw.Canvas, b GlyphBox) {
		x := c.X(b.X) + b.Rectangle.Min.X
		y := c.Y(b.Y) + b.Rectangle.Min.Y
		c.StrokeLines(sty, []vg.Point{
			{X: x, Y: y},
			{X: x + b.Rectangle.Size().X, Y: y},
			{X: x + b.Rectangle.Size().X, Y: y + b.Rectangle.Size().Y},
			{X: x, Y: y + b.Rectangle.Size().Y},
			{X: x, Y: y},
		})
	}

	var title vg.Length
	if p.Title.Text != "" {
		rect := p.Title.TextStyle.Rectangle(p.Title.Text)
		title += rect.Size().Y
		title += p.Title.Padding
		box := GlyphBox{
			Rectangle: rect.Add(vg.Point{
				X: c.Center().X,
				Y: c.Max.Y,
			}),
		}
		drawBox(c, box)
	}

	for _, b := range p.GlyphBoxes(p) {
		drawBox(dac, b)
	}

	p.X.sanitizeRange()
	p.Y.sanitizeRange()

	x := horizontalAxis{p.X}
	y := verticalAxis{p.Y}

	ywidth := y.size()
	xheight := x.size()

	cx := padX(p, draw.Crop(c, ywidth, 0, 0, 0))
	for _, b := range x.GlyphBoxes(p) {
		drawBox(cx, b)
	}

	cy := padY(p, draw.Crop(c, 0, 0, xheight, 0))
	cy.Max.Y -= title
	for _, b := range y.GlyphBoxes(p) {
		drawBox(cy, b)
	}
}