fixed dependencies

vendor/gonum.org/v1/plot/plotter/labels.go

@@ -0,0 +1,125 @@
+// Copyright ©2015 The Gonum Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package plotter
+
+import (
+	"errors"
+
+	"gonum.org/v1/plot"
+	"gonum.org/v1/plot/font"
+	"gonum.org/v1/plot/text"
+	"gonum.org/v1/plot/vg"
+	"gonum.org/v1/plot/vg/draw"
+)
+
+var (
+	// DefaultFont is the default font for label text.
+	DefaultFont = plot.DefaultFont
+
+	// DefaultFontSize is the default font.
+	DefaultFontSize = vg.Points(10)
+)
+
+// Labels implements the Plotter interface,
+// drawing a set of labels at specified points.
+type Labels struct {
+	XYs
+
+	// Labels is the set of labels corresponding
+	// to each point.
+	Labels []string
+
+	// TextStyle is the style of the label text. Each label
+	// can have a different text style.
+	TextStyle []text.Style
+
+	// Offset is added directly to the final label location.
+	Offset vg.Point
+}
+
+// NewLabels returns a new Labels using the DefaultFont and
+// the DefaultFontSize.
+func NewLabels(d XYLabeller) (*Labels, error) {
+	xys, err := CopyXYs(d)
+	if err != nil {
+		return nil, err
+	}
+
+	if d.Len() != len(xys) {
+		return nil, errors.New("plotter: number of points does not match the number of labels")
+	}
+
+	strs := make([]string, d.Len())
+	for i := range strs {
+		strs[i] = d.Label(i)
+	}
+
+	styles := make([]text.Style, d.Len())
+	for i := range styles {
+		styles[i] = text.Style{
+			Font:    font.From(DefaultFont, DefaultFontSize),
+			Handler: plot.DefaultTextHandler,
+		}
+	}
+
+	return &Labels{
+		XYs:       xys,
+		Labels:    strs,
+		TextStyle: styles,
+	}, nil
+}
+
+// Plot implements the Plotter interface, drawing labels.
+func (l *Labels) Plot(c draw.Canvas, p *plot.Plot) {
+	trX, trY := p.Transforms(&c)
+	for i, label := range l.Labels {
+		pt := vg.Point{X: trX(l.XYs[i].X), Y: trY(l.XYs[i].Y)}
+		if !c.Contains(pt) {
+			continue
+		}
+		pt = pt.Add(l.Offset)
+		c.FillText(l.TextStyle[i], pt, label)
+	}
+}
+
+// DataRange returns the minimum and maximum X and Y values
+func (l *Labels) DataRange() (xmin, xmax, ymin, ymax float64) {
+	return XYRange(l)
+}
+
+// GlyphBoxes returns a slice of GlyphBoxes,
+// one for each of the labels, implementing the
+// plot.GlyphBoxer interface.
+func (l *Labels) GlyphBoxes(p *plot.Plot) []plot.GlyphBox {
+	bs := make([]plot.GlyphBox, len(l.Labels))
+	for i, label := range l.Labels {
+		bs[i] = plot.GlyphBox{
+			X:         p.X.Norm(l.XYs[i].X),
+			Y:         p.Y.Norm(l.XYs[i].Y),
+			Rectangle: l.TextStyle[i].Rectangle(label).Add(l.Offset),
+		}
+	}
+	return bs
+}
+
+// XYLabeller combines the XYer and Labeller types.
+type XYLabeller interface {
+	XYer
+	Labeller
+}
+
+// XYLabels holds XY data with labels.
+// The ith label corresponds to the ith XY.
+type XYLabels struct {
+	XYs
+	Labels []string
+}
+
+// Label returns the label for point index i.
+func (l XYLabels) Label(i int) string {
+	return l.Labels[i]
+}
+
+var _ XYLabeller = (*XYLabels)(nil)