s/LineChart/Plot and add ScatterPlot mode to it

CHANGELOG.md

@@ -1,5 +1,12 @@
 Feel free to search/open an issue if something is missing or confusing from the changelog, since many things have been in flux.
 
+## 2019/01/24
+
+Breaking changes:
+
+- Change LineChart to Plot
+  - Added ScatterPlot mode which plots points instead of lines between points
+
 ## 2019/01/23
 
 Non breaking changes:

README.md

@@ -28,10 +28,10 @@ If you upgrade and notice something is missing or don't like a change, revert th
 - [BarChart](./_examples/barchart.go)
 - [Canvas](./_examples/canvas.go)
 - [Gauge](./_examples/gauge.go)
-- [LineChart](./_examples/linechart.go)
 - [List](./_examples/list.go)
 - [Paragraph](./_examples/paragraph.go)
 - [PieChart](./_examples/piechart.go)
+- [Plot](./_examples/plot.go)
 - [Sparkline](./_examples/sparkline.go)
 - [StackedBarChart](./_examples/stacked_barchart.go)
 - [Table](./_examples/table.go)

_examples/linechart.go

@@ -1,72 +0,0 @@
-// Copyright 2017 Zack Guo <zack.y.guo@gmail.com>. All rights reserved.
-// Use of this source code is governed by a MIT license that can
-// be found in the LICENSE file.
-
-// +build ignore
-
-package main
-
-import (
-	"log"
-	"math"
-
-	ui "github.com/gizak/termui"
-	"github.com/gizak/termui/widgets"
-)
-
-func main() {
-	if err := ui.Init(); err != nil {
-		log.Fatalf("failed to initialize termui: %v", err)
-	}
-	defer ui.Close()
-
-	sinData := func() [][]float64 {
-		n := 220
-		data := make([][]float64, 2)
-		data[0] = make([]float64, n)
-		data[1] = make([]float64, n)
-		for i := 0; i < n; i++ {
-			data[0][i] = 1 + math.Sin(float64(i)/5)
-			data[1][i] = 1 + math.Cos(float64(i)/5)
-		}
-		return data
-	}()
-
-	lc0 := widgets.NewLineChart()
-	lc0.Title = "braille-mode Line Chart"
-	lc0.Data = sinData
-	lc0.SetRect(0, 0, 50, 15)
-	lc0.AxesColor = ui.ColorWhite
-	lc0.LineColors[0] = ui.ColorGreen
-
-	lc1 := widgets.NewLineChart()
-	lc1.Title = "custom Line Chart"
-	lc1.LineType = widgets.DotLine
-	lc1.Data = [][]float64{[]float64{1, 2, 3, 4, 5}}
-	lc1.SetRect(50, 0, 75, 10)
-	lc1.DotChar = '+'
-	lc1.AxesColor = ui.ColorWhite
-	lc1.LineColors[0] = ui.ColorYellow
-	lc1.DrawDirection = widgets.DrawLeft
-
-	lc2 := widgets.NewLineChart()
-	lc2.Title = "dot-mode Line Chart"
-	lc2.LineType = widgets.DotLine
-	lc2.Data = make([][]float64, 2)
-	lc2.Data[0] = sinData[0][4:]
-	lc2.Data[1] = sinData[1][4:]
-	lc2.SetRect(0, 15, 50, 30)
-	lc2.AxesColor = ui.ColorWhite
-	lc2.LineColors[0] = ui.ColorCyan
-
-	ui.Render(lc0, lc1, lc2)
-
-	uiEvents := ui.PollEvents()
-	for {
-		e := <-uiEvents
-		switch e.ID {
-		case "q", "<C-c>":
-			return
-		}
-	}
-}

_examples/plot.go

@@ -0,0 +1,84 @@
+// Copyright 2017 Zack Guo <zack.y.guo@gmail.com>. All rights reserved.
+// Use of this source code is governed by a MIT license that can
+// be found in the LICENSE file.
+
+// +build ignore
+
+package main
+
+import (
+	"log"
+	"math"
+
+	ui "github.com/gizak/termui"
+	"github.com/gizak/termui/widgets"
+)
+
+func main() {
+	if err := ui.Init(); err != nil {
+		log.Fatalf("failed to initialize termui: %v", err)
+	}
+	defer ui.Close()
+
+	sinData := func() [][]float64 {
+		n := 220
+		data := make([][]float64, 2)
+		data[0] = make([]float64, n)
+		data[1] = make([]float64, n)
+		for i := 0; i < n; i++ {
+			data[0][i] = 1 + math.Sin(float64(i)/5)
+			data[1][i] = 1 + math.Cos(float64(i)/5)
+		}
+		return data
+	}()
+
+	p0 := widgets.NewPlot()
+	p0.Title = "braille-mode Line Chart"
+	p0.Data = sinData
+	p0.SetRect(0, 0, 50, 15)
+	p0.AxesColor = ui.ColorWhite
+	p0.LineColors[0] = ui.ColorGreen
+
+	p1 := widgets.NewPlot()
+	p1.Title = "custom Line Chart"
+	p1.Marker = widgets.MarkerDot
+	p1.Data = [][]float64{[]float64{1, 2, 3, 4, 5}}
+	p1.SetRect(50, 0, 75, 10)
+	p1.DotRune = '+'
+	p1.AxesColor = ui.ColorWhite
+	p1.LineColors[0] = ui.ColorYellow
+	p1.DrawDirection = widgets.DrawLeft
+
+	p2 := widgets.NewPlot()
+	p2.Title = "dot-mode Scatter Plot"
+	p2.Marker = widgets.MarkerDot
+	p2.Data = make([][]float64, 2)
+	p2.Data[0] = []float64{1, 2, 3, 4, 5}
+	p2.Data[1] = sinData[1][4:]
+	p2.SetRect(0, 15, 50, 30)
+	p2.AxesColor = ui.ColorWhite
+	p2.LineColors[0] = ui.ColorCyan
+	p2.Type = widgets.ScatterPlot
+
+	p3 := widgets.NewPlot()
+	p3.Title = "dot-mode Scatter Plot"
+	p3.Data = make([][]float64, 2)
+	p3.Data[0] = []float64{1, 2, 3, 4, 5}
+	p3.Data[1] = sinData[1][4:]
+	p3.SetRect(45, 15, 80, 30)
+	p3.AxesColor = ui.ColorWhite
+	p3.LineColors[0] = ui.ColorCyan
+	p3.Marker = widgets.MarkerBraille
+	p3.Type = widgets.ScatterPlot
+
+	ui.Render(p0, p1, p2, p3)
+
+	uiEvents := ui.PollEvents()
+	for {
+		e := <-uiEvents
+		switch e.ID {
+		case "q", "<C-c>":
+			return
+		}
+	}
+}

canvas.go

@@ -54,6 +54,14 @@ func (self *Canvas) Line(p0, p1 image.Point, color Color) {
 	}
 }
 
+func (self *Canvas) Point(p image.Point, color Color) {
+	point := image.Pt(p.X/2, p.Y/4)
+	self.CellMap[point] = Cell{
+		self.CellMap[point].Rune | BRAILLE[p.X%4][p.Y%2],
+		NewStyle(color),
+	}
+}
+
 func (self *Canvas) Draw(buf *Buffer) {
 	for point, cell := range self.CellMap {
 		if point.In(self.Rectangle) {

theme.go

@@ -31,7 +31,7 @@ type RootTheme struct {
 
 	BarChart        BarChartTheme
 	Gauge           GaugeTheme
-	LineChart       LineChartTheme
+	Plot            PlotTheme
 	List            ListTheme
 	Paragraph       ParagraphTheme
 	PieChart        PieChartTheme
@@ -57,7 +57,7 @@ type GaugeTheme struct {
 	Label Style
 }
 
-type LineChartTheme struct {
+type PlotTheme struct {
 	Lines []Color
 	Axes  Color
 }
@@ -136,7 +136,7 @@ var Theme = RootTheme{
 		Line:  ColorWhite,
 	},
 
-	LineChart: LineChartTheme{
+	Plot: PlotTheme{
 		Lines: StandardColors,
 		Axes:  ColorWhite,
 	},

widgets/plot.go

@@ -11,20 +11,25 @@ import (
 	. "github.com/gizak/termui"
 )
 
-// LineChart has two modes: braille(default) and dot.
+// Plot has two modes: line(default) and scatter.
+// Plot also has two marker types: braille(default) and dot.
 // A single braille character is a 2x4 grid of dots, so using braille
 // gives 2x X resolution and 4x Y resolution over dot mode.
-type LineChart struct {
+type Plot struct {
 	Block
-	Data            [][]float64
+
-	DataLabels      []string
+	Data       [][]float64
+	DataLabels []string
+	MaxVal     float64
+
+	LineColors []Color
+	AxesColor  Color // TODO
+	ShowAxes   bool
+
+	Marker          PlotMarker
+	DotRune         rune
+	Type            PlotType
 	HorizontalScale int
-	LineType        LineType
-	DotChar         rune
-	LineColors      []Color
-	AxesColor       Color // TODO
-	MaxVal          float64
-	ShowAxes        bool
 	DrawDirection   DrawDirection // TODO
 }
 
@@ -35,11 +40,18 @@ const (
 	yAxisLabelsGap    = 1
 )
 
-type LineType int
+type PlotType uint
 
 const (
-	BrailleLine LineType = iota
+	LineChart PlotType = iota
-	DotLine
+	ScatterPlot
+)
+
+type PlotMarker uint
+
+const (
+	MarkerBraille PlotMarker = iota
+	MarkerDot
 )
 
 type DrawDirection uint
@@ -49,60 +61,93 @@ const (
 	DrawRight
 )
 
-func NewLineChart() *LineChart {
+func NewPlot() *Plot {
-	return &LineChart{
+	return &Plot{
 		Block:           *NewBlock(),
-		LineColors:      Theme.LineChart.Lines,
+		LineColors:      Theme.Plot.Lines,
-		AxesColor:       Theme.LineChart.Axes,
+		AxesColor:       Theme.Plot.Axes,
-		LineType:        BrailleLine,
+		Marker:          MarkerBraille,
-		DotChar:         DOT,
+		DotRune:         DOT,
 		Data:            [][]float64{},
 		HorizontalScale: 1,
 		DrawDirection:   DrawRight,
 		ShowAxes:        true,
+		Type:            LineChart,
 	}
 }
 
-func (self *LineChart) renderBraille(buf *Buffer, drawArea image.Rectangle, maxVal float64) {
+func (self *Plot) renderBraille(buf *Buffer, drawArea image.Rectangle, maxVal float64) {
 	canvas := NewCanvas()
 	canvas.Rectangle = drawArea
 
-	for i, line := range self.Data {
+	switch self.Type {
-		previousHeight := int((line[1] / maxVal) * float64(drawArea.Dy()-1))
+	case ScatterPlot:
-		for j, val := range line[1:] {
+		for i, line := range self.Data {
-			height := int((val / maxVal) * float64(drawArea.Dy()-1))
+			for j, val := range line {
-			canvas.Line(
+				height := int((val / maxVal) * float64(drawArea.Dy()-1))
-				image.Pt(
+				canvas.Point(
-					(drawArea.Min.X+(j*self.HorizontalScale))*2,
+					image.Pt(
-					(drawArea.Max.Y-previousHeight-1)*4,
+						(drawArea.Min.X+(j*self.HorizontalScale))*2,
-				),
+						(drawArea.Max.Y-height-1)*4,
-				image.Pt(
+					),
-					(drawArea.Min.X+((j+1)*self.HorizontalScale))*2,
+					SelectColor(self.LineColors, i),
-					(drawArea.Max.Y-height-1)*4,
+				)
-				),
+			}
-				SelectColor(self.LineColors, i),
+		}
-			)
+	case LineChart:
-			previousHeight = height
+		for i, line := range self.Data {
+			previousHeight := int((line[1] / maxVal) * float64(drawArea.Dy()-1))
+			for j, val := range line[1:] {
+				height := int((val / maxVal) * float64(drawArea.Dy()-1))
+				canvas.Line(
+					image.Pt(
+						(drawArea.Min.X+(j*self.HorizontalScale))*2,
+						(drawArea.Max.Y-previousHeight-1)*4,
+					),
+					image.Pt(
+						(drawArea.Min.X+((j+1)*self.HorizontalScale))*2,
+						(drawArea.Max.Y-height-1)*4,
+					),
+					SelectColor(self.LineColors, i),
+				)
+				previousHeight = height
+			}
 		}
 	}
 
 	canvas.Draw(buf)
 }
 
-func (self *LineChart) renderDot(buf *Buffer, drawArea image.Rectangle, maxVal float64) {
+func (self *Plot) renderDot(buf *Buffer, drawArea image.Rectangle, maxVal float64) {
-	for i, line := range self.Data {
+	switch self.Type {
-		for j := 0; j < len(line) && j*self.HorizontalScale < drawArea.Dx(); j++ {
+	case ScatterPlot:
-			val := line[j]
+		for i, line := range self.Data {
-			height := int((val / maxVal) * float64(drawArea.Dy()-1))
+			for j, val := range line {
-			buf.SetCell(
+				height := int((val / maxVal) * float64(drawArea.Dy()-1))
-				NewCell(self.DotChar, NewStyle(SelectColor(self.LineColors, i))),
+				point := image.Pt(drawArea.Min.X+(j*self.HorizontalScale), drawArea.Max.Y-1-height)
-				image.Pt(drawArea.Min.X+(j*self.HorizontalScale), drawArea.Max.Y-1-height),
+				if point.In(drawArea) {
-			)
+					buf.SetCell(
+						NewCell(self.DotRune, NewStyle(SelectColor(self.LineColors, i))),
+						point,
+					)
+				}
+			}
+		}
+	case LineChart:
+		for i, line := range self.Data {
+			for j := 0; j < len(line) && j*self.HorizontalScale < drawArea.Dx(); j++ {
+				val := line[j]
+				height := int((val / maxVal) * float64(drawArea.Dy()-1))
+				buf.SetCell(
+					NewCell(self.DotRune, NewStyle(SelectColor(self.LineColors, i))),
+					image.Pt(drawArea.Min.X+(j*self.HorizontalScale), drawArea.Max.Y-1-height),
+				)
+			}
 		}
 	}
 }
 
-func (self *LineChart) plotAxes(buf *Buffer, maxVal float64) {
+func (self *Plot) plotAxes(buf *Buffer, maxVal float64) {
 	// draw origin cell
 	buf.SetCell(
 		NewCell(BOTTOM_LEFT, NewStyle(ColorWhite)),
@@ -153,7 +198,7 @@ func (self *LineChart) plotAxes(buf *Buffer, maxVal float64) {
 	}
 }
 
-func (self *LineChart) Draw(buf *Buffer) {
+func (self *Plot) Draw(buf *Buffer) {
 	self.Block.Draw(buf)
 
 	maxVal := self.MaxVal
@@ -173,9 +218,10 @@ func (self *LineChart) Draw(buf *Buffer) {
 		)
 	}
 
-	if self.LineType == BrailleLine {
+	switch self.Marker {
+	case MarkerBraille:
 		self.renderBraille(buf, drawArea, maxVal)
-	} else {
+	case MarkerDot:
 		self.renderDot(buf, drawArea, maxVal)
 	}
 }