// NewLabels returns a new Labels using the DefaultFont and
// the DefaultFontSize.
func NewLabels(d interface {
XYer
Labeller
}) (*Labels, error) {
xys, err := CopyXYs(d)
if err != nil {
return nil, err
}
if d.Len() != len(xys) {
return nil, errors.New("Number of points does not match the number of labels")
}
strs := make([]string, d.Len())
for i := range strs {
strs[i] = d.Label(i)
}
fnt, err := vg.MakeFont(DefaultFont, DefaultFontSize)
if err != nil {
return nil, err
}
return &Labels{
XYs: xys,
Labels: strs,
TextStyle: draw.TextStyle{Font: fnt},
}, nil
}
// New returns a new plot with some reasonable
// default settings.
func New() (*Plot, error) {
titleFont, err := vg.MakeFont(DefaultFont, 12)
if err != nil {
return nil, err
}
x, err := makeAxis()
if err != nil {
return nil, err
}
y, err := makeAxis()
if err != nil {
return nil, err
}
legend, err := makeLegend()
if err != nil {
return nil, err
}
p := &Plot{
BackgroundColor: color.White,
X: x,
Y: y,
Legend: legend,
}
p.Title.TextStyle = draw.TextStyle{
Color: color.Black,
Font: titleFont,
}
return p, nil
}
// makeLegend returns a legend with the default
// parameter settings.
func makeLegend() (Legend, error) {
font, err := vg.MakeFont(DefaultFont, vg.Points(12))
if err != nil {
return Legend{}, err
}
return Legend{
ThumbnailWidth: vg.Points(20),
TextStyle: draw.TextStyle{Font: font},
}, nil
}
// makeAxis returns a default Axis.
//
// The default range is (∞, ∞), and thus any finite
// value is less than Min and greater than Max.
func makeAxis() (Axis, error) {
labelFont, err := vg.MakeFont(DefaultFont, vg.Points(12))
if err != nil {
return Axis{}, err
}
tickFont, err := vg.MakeFont(DefaultFont, vg.Points(10))
if err != nil {
return Axis{}, err
}
a := Axis{
Min: math.Inf(1),
Max: math.Inf(-1),
LineStyle: draw.LineStyle{
Color: color.Black,
Width: vg.Points(0.5),
},
Padding: vg.Points(5),
Scale: LinearScale{},
}
a.Label.TextStyle = draw.TextStyle{
Color: color.Black,
Font: labelFont,
}
a.Tick.Label = draw.TextStyle{
Color: color.Black,
Font: tickFont,
}
a.Tick.LineStyle = draw.LineStyle{
Color: color.Black,
Width: vg.Points(0.5),
}
a.Tick.Length = vg.Points(8)
a.Tick.Marker = DefaultTicks{}
return a, nil
}
// ReplayOn applies the set of Actions recorded by the Recorder onto
// the destination Canvas.
func (c *Canvas) ReplayOn(dst vg.Canvas) error {
if c.fonts == nil {
c.fonts = make(map[fontID]vg.Font)
}
for _, a := range c.Actions {
fa, ok := a.(*FillString)
if !ok {
continue
}
f := fontID{name: fa.Font, size: fa.Size}
if _, exists := c.fonts[f]; !exists {
var err error
c.fonts[f], err = vg.MakeFont(fa.Font, fa.Size)
if err != nil {
return err
}
}
fa.fonts = c.fonts
}
for _, a := range c.Actions {
a.ApplyTo(dst)
}
return nil
}
func TestLegendAlignment(t *testing.T) {
font, err := vg.MakeFont(plot.DefaultFont, 10.822510822510822) // This font size gives an entry height of 10.
if err != nil {
t.Fatalf("failed to create font: %v", err)
}
l := plot.Legend{
ThumbnailWidth: vg.Points(20),
TextStyle: draw.TextStyle{Font: font},
}
for _, n := range []string{"A", "B", "C", "D"} {
b, err := plotter.NewBarChart(plotter.Values{0}, 1)
if err != nil {
t.Fatalf("failed to create bar chart %q: %v", n, err)
}
l.Add(n, b)
}
r := recorder.New(100)
c := draw.NewCanvas(r, 100, 100)
l.Draw(draw.Canvas{
Canvas: c.Canvas,
Rectangle: draw.Rectangle{
Min: draw.Point{0, 0},
Max: draw.Point{100, 100},
},
})
got := r.Actions
// want is a snapshot of the actions for the code above when the
// graphical output has been visually confirmed to be correct for
// the bar charts example show in gonum/plot#25.
want := []recorder.Action{
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.Fill{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 30},
{Type: vg.LineComp, X: 80, Y: 40},
{Type: vg.LineComp, X: 100, Y: 40},
{Type: vg.LineComp, X: 100, Y: 30},
{Type: vg.CloseComp},
},
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.SetLineWidth{
Width: 1,
},
&recorder.SetLineDash{},
&recorder.Stroke{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 30},
{Type: vg.LineComp, X: 80, Y: 40},
{Type: vg.LineComp, X: 100, Y: 40},
{Type: vg.LineComp, X: 100, Y: 30},
{Type: vg.LineComp, X: 80, Y: 30},
},
},
&recorder.SetColor{},
&recorder.FillString{
Font: string("Times-Roman"),
Size: 10.822510822510822,
X: 69.48051948051948,
Y: 30.82251082251082,
String: "A",
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.Fill{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 20},
{Type: vg.LineComp, X: 80, Y: 30},
{Type: vg.LineComp, X: 100, Y: 30},
{Type: vg.LineComp, X: 100, Y: 20},
{Type: vg.CloseComp},
},
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.SetLineWidth{
Width: 1,
},
&recorder.SetLineDash{},
&recorder.Stroke{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 20},
{Type: vg.LineComp, X: 80, Y: 30},
{Type: vg.LineComp, X: 100, Y: 30},
{Type: vg.LineComp, X: 100, Y: 20},
{Type: vg.LineComp, X: 80, Y: 20},
},
},
&recorder.SetColor{},
&recorder.FillString{
Font: string("Times-Roman"),
Size: 10.822510822510822,
X: 70.07575757575758,
Y: 20.82251082251082,
String: "B",
},
&recorder.SetColor{
Color: color.Gray16{
Y: uint16(0),
},
},
&recorder.Fill{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 10},
{Type: vg.LineComp, X: 80, Y: 20},
{Type: vg.LineComp, X: 100, Y: 20},
{Type: vg.LineComp, X: 100, Y: 10},
{Type: vg.CloseComp},
},
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.SetLineWidth{
Width: 1,
},
&recorder.SetLineDash{},
&recorder.Stroke{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 10},
{Type: vg.LineComp, X: 80, Y: 20},
{Type: vg.LineComp, X: 100, Y: 20},
{Type: vg.LineComp, X: 100, Y: 10},
{Type: vg.LineComp, X: 80, Y: 10},
},
},
&recorder.SetColor{},
&recorder.FillString{
Font: string("Times-Roman"),
Size: 10.822510822510822,
X: 70.07575757575758,
Y: 10.822510822510822,
String: "C",
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.Fill{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 0},
{Type: vg.LineComp, X: 80, Y: 10},
{Type: vg.LineComp, X: 100, Y: 10},
{Type: vg.LineComp, X: 100, Y: 0},
{Type: vg.CloseComp},
},
},
&recorder.SetColor{
Color: color.Gray16{},
},
&recorder.SetLineWidth{
Width: 1,
},
&recorder.SetLineDash{},
&recorder.Stroke{
Path: vg.Path{
{Type: vg.MoveComp, X: 80, Y: 0},
{Type: vg.LineComp, X: 80, Y: 10},
{Type: vg.LineComp, X: 100, Y: 10},
{Type: vg.LineComp, X: 100, Y: 0},
{Type: vg.LineComp, X: 80, Y: 0},
},
},
&recorder.SetColor{},
&recorder.FillString{
Font: string("Times-Roman"),
Size: 10.822510822510822,
X: 69.48051948051948,
Y: 0.8225108225108215,
String: "D",
},
}
if !reflect.DeepEqual(got, want) {
t.Errorf("unexpected legend actions:\ngot:\n%s\nwant:\n%s", formatActions(got), formatActions(want))
}
}