Merge pull request #31 from dhilipkumars/MultiColorBarGraph

Implement Multi-colored/Stacked barGraph

example/mbarchart.go

@@ -0,0 +1,48 @@
+// Copyright 2015 Zack Guo <gizak@icloud.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 "github.com/gizak/termui"
+
+func main() {
+	err := termui.Init()
+	if err != nil {
+		panic(err)
+	}
+	defer termui.Close()
+
+	termui.UseTheme("helloworld")
+
+	bc := termui.NewMBarChart()
+	math := []int{45, 75, 34, 62}
+	english := []int{50, 45, 25, 57}
+	science := []int{75, 60, 15, 50}
+	compsci := []int{90, 95, 100, 100}
+	bc.Data[0] = math
+	bc.Data[1] = english
+	bc.Data[2] = science
+	bc.Data[3] = compsci
+	studentsName := []string{"Ken", "Rob", "Dennis", "Linus"}
+	bc.Border.Label = "Student's Marks X-Axis=Name Y-Axis=Marks[Math,English,Science,ComputerScience] in %"
+	bc.Width = 100
+	bc.Height = 50
+	bc.Y = 10
+	bc.BarWidth = 10
+	bc.DataLabels = studentsName
+
+	bc.TextColor = termui.ColorGreen    //this is color for label (x-axis)
+	bc.BarColor[3] = termui.ColorGreen  //BarColor for computerscience
+	bc.BarColor[1] = termui.ColorYellow //Bar Color for english
+	bc.NumColor[3] = termui.ColorRed    // Num color for computerscience
+	bc.NumColor[1] = termui.ColorRed    // num color for english
+
+	//Other colors are automatically populated, btw All the students seems do well in computerscience. :p
+
+	termui.Render(bc)
+
+	<-termui.EventCh()
+}

helper.go

@@ -24,6 +24,7 @@ const (
 	ColorWhite
 )
 
+const NumberofColors = 8 //Have a constant that defines number of colors
 const (
 	AttrBold Attribute = 1 << (iota + 9)
 	AttrUnderline

mbar.go

@@ -0,0 +1,198 @@
+// Copyright 2015 Zack Guo <gizak@icloud.com>. All rights reserved.
+// Use of this source code is governed by a MIT license that can
+// be found in the LICENSE file.
+
+package termui
+
+import (
+	"fmt"
+)
+
+// This is the implemetation of multi-colored or stacked bar graph.  This is different from default barGraph which is implemented in bar.go
+// Multi-Colored-BarChart creates multiple bars in a widget:
+/*
+   bc := termui.NewMBarChart()
+   data := make([][]int, 2)
+   data[0] := []int{3, 2, 5, 7, 9, 4}
+   data[1] := []int{7, 8, 5, 3, 1, 6}
+   bclabels := []string{"S0", "S1", "S2", "S3", "S4", "S5"}
+   bc.Border.Label = "Bar Chart"
+   bc.Data = data
+   bc.Width = 26
+   bc.Height = 10
+   bc.DataLabels = bclabels
+   bc.TextColor = termui.ColorGreen
+   bc.BarColor = termui.ColorRed
+   bc.NumColor = termui.ColorYellow
+*/
+type MBarChart struct {
+	Block
+	BarColor   [NumberofColors]Attribute
+	TextColor  Attribute
+	NumColor   [NumberofColors]Attribute
+	Data       [NumberofColors][]int
+	DataLabels []string
+	BarWidth   int
+	BarGap     int
+	labels     [][]rune
+	dataNum    [NumberofColors][][]rune
+	numBar     int
+	scale      float64
+	max        int
+	minDataLen int
+	numStack   int
+}
+
+// NewBarChart returns a new *BarChart with current theme.
+func NewMBarChart() *MBarChart {
+	bc := &MBarChart{Block: *NewBlock()}
+	bc.BarColor[0] = theme.MBarChartBar
+	bc.NumColor[0] = theme.MBarChartNum
+	bc.TextColor = theme.MBarChartText
+	bc.BarGap = 1
+	bc.BarWidth = 3
+	return bc
+}
+
+func (bc *MBarChart) layout() {
+	bc.numBar = bc.innerWidth / (bc.BarGap + bc.BarWidth)
+	bc.labels = make([][]rune, bc.numBar)
+	DataLen := 0
+	LabelLen := len(bc.DataLabels)
+	bc.minDataLen = 9999 //Set this to some very hight value so that we find the minimum one We want to know which array among data[][] has got the least lenght
+
+	// We need to know how many stack/data array data[0] , data[1] are there
+	for i := 0; i < len(bc.Data); i++ {
+		if bc.Data[i] == nil {
+			break
+		}
+		DataLen++
+	}
+	bc.numStack = DataLen
+
+	//We need to what is the mimimum size of data array data[0] could have 10 elements data[1] could have only 5, so we plot only 5 bar graphs
+
+	for i := 0; i < DataLen; i++ {
+		if bc.minDataLen > len(bc.Data[i]) {
+			bc.minDataLen = len(bc.Data[i])
+		}
+	}
+
+	if LabelLen > bc.minDataLen {
+		LabelLen = bc.minDataLen
+	}
+
+	for i := 0; i < LabelLen && i < bc.numBar; i++ {
+		bc.labels[i] = trimStr2Runes(bc.DataLabels[i], bc.BarWidth)
+	}
+
+	for i := 0; i < bc.numStack; i++ {
+		bc.dataNum[i] = make([][]rune, len(bc.Data[i]))
+		//For each stack of bar calcualte the rune
+		for j := 0; j < LabelLen && i < bc.numBar; j++ {
+			n := bc.Data[i][j]
+			s := fmt.Sprint(n)
+			bc.dataNum[i][j] = trimStr2Runes(s, bc.BarWidth)
+		}
+		//If color is not defined by default then populate a color that is different from the prevous bar
+		if bc.BarColor[i] == ColorDefault && bc.NumColor[i] == ColorDefault {
+			if i == 0 {
+				bc.BarColor[i] = ColorBlack
+			} else {
+				bc.BarColor[i] = bc.BarColor[i-1] + 1
+				if bc.BarColor[i] > NumberofColors {
+					bc.BarColor[i] = ColorBlack
+				}
+			}
+			bc.NumColor[i] = (NumberofColors + 1) - bc.BarColor[i] //Make NumColor opposite of barColor for visibility
+		}
+	}
+
+	//If Max value is not set then we have to populate, this time the max value will be max(sum(d1[0],d2[0],d3[0]) .... sum(d1[n], d2[n], d3[n]))
+
+	if bc.max == 0 {
+		bc.max = -1
+	}
+	for i := 0; i < bc.minDataLen && i < LabelLen; i++ {
+		var dsum int
+		for j := 0; j < bc.numStack; j++ {
+			dsum += bc.Data[j][i]
+		}
+		if dsum > bc.max {
+			bc.max = dsum
+		}
+	}
+	bc.scale = float64(bc.max) / float64(bc.innerHeight-1)
+}
+
+func (bc *MBarChart) SetMax(max int) {
+
+	if max > 0 {
+		bc.max = max
+	}
+}
+
+// Buffer implements Bufferer interface.
+func (bc *MBarChart) Buffer() []Point {
+	ps := bc.Block.Buffer()
+	bc.layout()
+	var oftX int
+
+	for i := 0; i < bc.numBar && i < bc.minDataLen && i < len(bc.DataLabels); i++ {
+		ph := 0 //Previous Height to stack up
+		for i1 := 0; i1 < bc.numStack; i1++ {
+			h := int(float64(bc.Data[i1][i]) / bc.scale)
+			oftX = i * (bc.BarWidth + bc.BarGap)
+			// plot bars
+			for j := 0; j < bc.BarWidth; j++ {
+				for k := 0; k < h; k++ {
+					p := Point{}
+					p.Ch = ' '
+					p.Bg = bc.BarColor[i1]
+					if bc.BarColor[i1] == ColorDefault { // when color is default, space char treated as transparent!
+						p.Bg |= AttrReverse
+					}
+					p.X = bc.innerX + i*(bc.BarWidth+bc.BarGap) + j
+					p.Y = bc.innerY + bc.innerHeight - 2 - k - ph
+					ps = append(ps, p)
+				}
+			}
+			ph += h
+		}
+		// plot text
+		for j, k := 0, 0; j < len(bc.labels[i]); j++ {
+			w := charWidth(bc.labels[i][j])
+			p := Point{}
+			p.Ch = bc.labels[i][j]
+			p.Bg = bc.BgColor
+			p.Fg = bc.TextColor
+			p.Y = bc.innerY + bc.innerHeight - 1
+			p.X = bc.innerX + oftX + k
+			ps = append(ps, p)
+			k += w
+		}
+		// plot num
+		ph = 0 //re-initialize previous height
+		for i1 := 0; i1 < bc.numStack; i1++ {
+			h := int(float64(bc.Data[i1][i]) / bc.scale)
+			for j := 0; j < len(bc.dataNum[i1][i]) && h > 0; j++ {
+				p := Point{}
+				p.Ch = bc.dataNum[i1][i][j]
+				p.Fg = bc.NumColor[i1]
+				p.Bg = bc.BarColor[i1]
+				if bc.BarColor[i1] == ColorDefault { // the same as above
+					p.Bg |= AttrReverse
+				}
+				if h == 0 {
+					p.Bg = bc.BgColor
+				}
+				p.X = bc.innerX + oftX + (bc.BarWidth-len(bc.dataNum[i1][i]))/2 + j
+				p.Y = bc.innerY + bc.innerHeight - 2 - ph
+				ps = append(ps, p)
+			}
+			ph += h
+		}
+	}
+
+	return bc.Block.chopOverflow(ps)
+}

theme.go

@@ -26,6 +26,9 @@ type ColorScheme struct {
 	BarChartBar       Attribute
 	BarChartText      Attribute
 	BarChartNum       Attribute
+	MBarChartBar      Attribute
+	MBarChartText     Attribute
+	MBarChartNum      Attribute
 }
 
 // default color scheme depends on the user's terminal setting.
@@ -52,6 +55,9 @@ var themeHelloWorld = ColorScheme{
 	BarChartBar:       ColorRed,
 	BarChartNum:       ColorWhite,
 	BarChartText:      ColorCyan,
+	MBarChartBar:      ColorRed,
+	MBarChartNum:      ColorWhite,
+	MBarChartText:     ColorCyan,
 }
 
 var theme = themeDefault // global dep