WIP use Buffer instead of []Point in Bufferer

Merge https://github.com/Matt3o12/termui.git colored-list
Merge https://github.com/funkygao/termui.git master
Add subdir widget
Use image Rectangle represent buffer area

block.go

@@ -4,22 +4,22 @@
 
 package termui
 
+import "image"
+
 // Block is a base struct for all other upper level widgets,
 // consider it as css: display:block.
 // Normally you do not need to create it manually.
 type Block struct {
+	Area          image.Rectangle
+	innerArea     image.Rectangle
 	X             int
 	Y             int
-	Border        labeledBorder
+	Border        LabeledBorder
 	IsDisplay     bool
 	HasBorder     bool
-	BgColor       Attribute
+	Bg            Attribute
 	Width         int
 	Height        int
-	innerWidth    int
-	innerHeight   int
-	innerX        int
-	innerY        int
 	PaddingTop    int
 	PaddingBottom int
 	PaddingLeft   int
@@ -31,75 +31,81 @@ func NewBlock() *Block {
 	d := Block{}
 	d.IsDisplay = true
 	d.HasBorder = theme.HasBorder
-	d.Border.BgColor = theme.BorderBg
+	d.Border.Left = true
-	d.Border.FgColor = theme.BorderFg
+	d.Border.Right = true
-	d.Border.LabelBgColor = theme.BorderLabelTextBg
+	d.Border.Top = true
-	d.Border.LabelFgColor = theme.BorderLabelTextFg
+	d.Border.Bottom = true
-	d.BgColor = theme.BlockBg
+	d.Border.Bg = theme.BorderBg
+	d.Border.Fg = theme.BorderFg
+	d.Border.LabelBgClr = theme.BorderLabelTextBg
+	d.Border.LabelFgClr = theme.BorderLabelTextFg
+	d.Bg = theme.BlockBg
 	d.Width = 2
 	d.Height = 2
 	return &d
 }
 
-// compute box model
+// Align computes box model
-func (d *Block) align() {
+func (d *Block) Align() {
-	d.innerWidth = d.Width - d.PaddingLeft - d.PaddingRight
+	d.Area.Min.X = d.X
-	d.innerHeight = d.Height - d.PaddingTop - d.PaddingBottom
+	d.Area.Min.Y = d.Y
-	d.innerX = d.X + d.PaddingLeft
+	d.Area.Max.X = d.X + d.Width - 1
-	d.innerY = d.Y + d.PaddingTop
+	d.Area.Max.Y = d.Y + d.Height - 1
+
+	d.innerArea.Min.X = d.X + d.PaddingLeft
+	d.innerArea.Min.Y = d.Y + d.PaddingTop
+	d.innerArea.Max.X = d.Area.Max.X - d.PaddingRight
+	d.innerArea.Max.Y = d.Area.Max.Y - d.PaddingBottom
+
+	d.Border.Area = d.Area
 
 	if d.HasBorder {
-		d.innerHeight -= 2
+		switch {
-		d.innerWidth -= 2
+		case d.Border.Left:
-		d.Border.X = d.X
+			d.innerArea.Min.X++
-		d.Border.Y = d.Y
+			fallthrough
-		d.Border.Width = d.Width
+		case d.Border.Right:
-		d.Border.Height = d.Height
+			d.innerArea.Max.X--
-		d.innerX++
+			fallthrough
-		d.innerY++
+		case d.Border.Top:
+			d.innerArea.Min.Y++
+			fallthrough
+		case d.Border.Bottom:
+			d.innerArea.Max.Y--
+		}
 	}
-
-	if d.innerHeight < 0 {
-		d.innerHeight = 0
-	}
-	if d.innerWidth < 0 {
-		d.innerWidth = 0
-	}
-
 }
 
 // InnerBounds returns the internal bounds of the block after aligning and
 // calculating the padding and border, if any.
-func (d *Block) InnerBounds() (x, y, width, height int) {
+func (d *Block) InnerBounds() image.Rectangle {
-	d.align()
+	d.Align()
-	return d.innerX, d.innerY, d.innerWidth, d.innerHeight
+	return d.innerArea
 }
 
 // Buffer implements Bufferer interface.
 // Draw background and border (if any).
-func (d *Block) Buffer() []Point {
+func (d *Block) Buffer() Buffer {
-	d.align()
+	d.Align()
 
-	ps := []Point{}
+	buf := NewBuffer()
+	buf.Area = d.Area
 	if !d.IsDisplay {
-		return ps
+		return buf
 	}
 
+	// render border
 	if d.HasBorder {
-		ps = d.Border.Buffer()
+		buf.Union(d.Border.Buffer())
 	}
 
-	for i := 0; i < d.innerWidth; i++ {
+	// render background
-		for j := 0; j < d.innerHeight; j++ {
+	for p := range buf.CellMap {
-			p := Point{}
+		if p.In(d.innerArea) {
-			p.X = d.X + 1 + i
+			buf.CellMap[p] = Cell{' ', ColorDefault, d.Bg}
-			p.Y = d.Y + 1 + j
-			p.Ch = ' '
-			p.Bg = d.BgColor
-			ps = append(ps, p)
 		}
 	}
-	return ps
+	return buf
 }
 
 // GetHeight implements GridBufferer.
@@ -122,21 +128,3 @@ func (d *Block) SetY(y int) {
 func (d *Block) SetWidth(w int) {
 	d.Width = w
 }
-
-// chop the overflow parts
-func (d *Block) chopOverflow(ps []Point) []Point {
-	nps := make([]Point, 0, len(ps))
-	x := d.X
-	y := d.Y
-	w := d.Width
-	h := d.Height
-	for _, v := range ps {
-		if v.X >= x &&
-			v.X < x+w &&
-			v.Y >= y &&
-			v.Y < y+h {
-			nps = append(nps, v)
-		}
-	}
-	return nps
-}

box.go

@@ -4,114 +4,120 @@
 
 package termui
 
-type border struct {
+import "image"
-	X       int
+
-	Y       int
+type Border struct {
-	Width   int
+	Area   image.Rectangle
-	Height  int
+	Left   bool
-	FgColor Attribute
+	Top    bool
-	BgColor Attribute
+	Right  bool
+	Bottom bool
+	Fg     Attribute
+	Bg     Attribute
 }
 
-type hline struct {
+type Hline struct {
-	X       int
+	X   int
-	Y       int
+	Y   int
-	Length  int
+	Len int
-	FgColor Attribute
+	Fg  Attribute
-	BgColor Attribute
+	Bg  Attribute
 }
 
-type vline struct {
+type Vline struct {
-	X       int
+	X   int
-	Y       int
+	Y   int
-	Length  int
+	Len int
-	FgColor Attribute
+	Fg  Attribute
-	BgColor Attribute
+	Bg  Attribute
 }
 
-// Draw a horizontal line.
+// Buffer draws a horizontal line.
-func (l hline) Buffer() []Point {
+func (l Hline) Buffer() Buffer {
-	pts := make([]Point, l.Length)
+	buf := NewBuffer()
-	for i := 0; i < l.Length; i++ {
+	for i := 0; i < l.Len; i++ {
-		pts[i].X = l.X + i
+		buf.Set(l.X+i, l.Y, Cell{HORIZONTAL_LINE, l.Fg, l.Bg})
-		pts[i].Y = l.Y
-		pts[i].Ch = HORIZONTAL_LINE
-		pts[i].Bg = l.BgColor
-		pts[i].Fg = l.FgColor
 	}
-	return pts
+	buf.Align()
+	return buf
 }
 
-// Draw a vertical line.
+// Buffer draws a vertical line.
-func (l vline) Buffer() []Point {
+func (l Vline) Buffer() Buffer {
-	pts := make([]Point, l.Length)
+	buf := NewBuffer()
-	for i := 0; i < l.Length; i++ {
+	for i := 0; i < l.Len; i++ {
-		pts[i].X = l.X
+		buf.Set(l.X, l.Y+i, Cell{VERTICAL_LINE, l.Fg, l.Bg})
-		pts[i].Y = l.Y + i
-		pts[i].Ch = VERTICAL_LINE
-		pts[i].Bg = l.BgColor
-		pts[i].Fg = l.FgColor
 	}
-	return pts
+	buf.Align()
+	return buf
 }
 
-// Draw a box border.
+// Buffer draws a box border.
-func (b border) Buffer() []Point {
+func (b Border) Buffer() Buffer {
-	if b.Width < 2 || b.Height < 2 {
+	buf := NewBuffer()
-		return nil
+	if b.Area.Size().X < 2 || b.Area.Size().Y < 2 {
-	}
+		return buf
-	pts := make([]Point, 2*b.Width+2*b.Height-4)
-
-	pts[0].X = b.X
-	pts[0].Y = b.Y
-	pts[0].Fg = b.FgColor
-	pts[0].Bg = b.BgColor
-	pts[0].Ch = TOP_LEFT
-
-	pts[1].X = b.X + b.Width - 1
-	pts[1].Y = b.Y
-	pts[1].Fg = b.FgColor
-	pts[1].Bg = b.BgColor
-	pts[1].Ch = TOP_RIGHT
-
-	pts[2].X = b.X
-	pts[2].Y = b.Y + b.Height - 1
-	pts[2].Fg = b.FgColor
-	pts[2].Bg = b.BgColor
-	pts[2].Ch = BOTTOM_LEFT
-
-	pts[3].X = b.X + b.Width - 1
-	pts[3].Y = b.Y + b.Height - 1
-	pts[3].Fg = b.FgColor
-	pts[3].Bg = b.BgColor
-	pts[3].Ch = BOTTOM_RIGHT
-
-	copy(pts[4:], (hline{b.X + 1, b.Y, b.Width - 2, b.FgColor, b.BgColor}).Buffer())
-	copy(pts[4+b.Width-2:], (hline{b.X + 1, b.Y + b.Height - 1, b.Width - 2, b.FgColor, b.BgColor}).Buffer())
-	copy(pts[4+2*b.Width-4:], (vline{b.X, b.Y + 1, b.Height - 2, b.FgColor, b.BgColor}).Buffer())
-	copy(pts[4+2*b.Width-4+b.Height-2:], (vline{b.X + b.Width - 1, b.Y + 1, b.Height - 2, b.FgColor, b.BgColor}).Buffer())
-
-	return pts
-}
-
-type labeledBorder struct {
-	border
-	Label        string
-	LabelFgColor Attribute
-	LabelBgColor Attribute
-}
-
-// Draw a box border with label.
-func (lb labeledBorder) Buffer() []Point {
-	ps := lb.border.Buffer()
-	maxTxtW := lb.Width - 2
-	rs := trimStr2Runes(lb.Label, maxTxtW)
-
-	for i, j, w := 0, 0, 0; i < len(rs); i++ {
-		w = charWidth(rs[i])
-		ps = append(ps, newPointWithAttrs(rs[i], lb.X+1+j, lb.Y, lb.LabelFgColor, lb.LabelBgColor))
-		j += w
 	}
 
-	return ps
+	min := b.Area.Min
+	max := b.Area.Max
+
+	x0 := min.X
+	y0 := min.Y
+	x1 := max.X
+	y1 := max.Y
+
+	// draw lines
+	switch {
+	case b.Top:
+		buf.Union(Hline{x0, y0, x1 - x0, b.Fg, b.Bg}.Buffer())
+		fallthrough
+	case b.Bottom:
+		buf.Union(Hline{x0, y1, x1 - x0, b.Fg, b.Bg}.Buffer())
+		fallthrough
+	case b.Left:
+		buf.Union(Vline{x0, y0, y1 - y0, b.Fg, b.Bg}.Buffer())
+		fallthrough
+	case b.Right:
+		buf.Union(Vline{x1, y0, y1 - y0, b.Fg, b.Bg}.Buffer())
+	}
+
+	// draw corners
+	switch {
+	case b.Top && b.Left:
+		buf.Set(x0, y0, Cell{TOP_LEFT, b.Fg, b.Bg})
+		fallthrough
+	case b.Top && b.Right:
+		buf.Set(x1, y0, Cell{TOP_RIGHT, b.Fg, b.Bg})
+		fallthrough
+	case b.Bottom && b.Left:
+		buf.Set(x0, y1, Cell{BOTTOM_LEFT, b.Fg, b.Bg})
+		fallthrough
+	case b.Bottom && b.Right:
+		buf.Set(x1, y1, Cell{BOTTOM_RIGHT, b.Fg, b.Bg})
+	}
+
+	return buf
+}
+
+// LabeledBorder defined label upon Border
+type LabeledBorder struct {
+	Border
+	Label      string
+	LabelFgClr Attribute
+	LabelBgClr Attribute
+}
+
+// Buffer draw a box border with label.
+func (lb LabeledBorder) Buffer() Buffer {
+	border := lb.Border.Buffer()
+	maxTxtW := lb.Area.Dx() + 1 - 2
+	tx := DTrimTxCls(TextCells(lb.Label, lb.LabelFgClr, lb.LabelBgClr), maxTxtW)
+
+	for i, w := 0, 0; i < len(tx); i++ {
+		border.Set(border.Area.Min.X+1+w, border.Area.Min.Y, tx[i])
+		w += tx[i].Width()
+	}
+
+	return border
 }

buffer.go

@@ -0,0 +1,89 @@
+// 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 "image"
+
+// Cell is a rune with assigned Fg and Bg
+type Cell struct {
+	Ch rune
+	Fg Attribute
+	Bg Attribute
+}
+
+// Buffer is a renderable rectangle cell data container.
+type Buffer struct {
+	Area    image.Rectangle // selected drawing area
+	CellMap map[image.Point]Cell
+}
+
+// At returns the cell at (x,y).
+func (b Buffer) At(x, y int) Cell {
+	return b.CellMap[image.Pt(x, y)]
+}
+
+// Set assigns a char to (x,y)
+func (b Buffer) Set(x, y int, c Cell) {
+	b.CellMap[image.Pt(x, y)] = c
+}
+
+// Bounds returns the domain for which At can return non-zero color.
+func (b Buffer) Bounds() image.Rectangle {
+	x0, y0, x1, y1 := 0, 0, 0, 0
+	for p := range b.CellMap {
+		switch {
+		case p.X > x1:
+			x1 = p.X
+		case p.X < x0:
+			x0 = p.X
+		case p.Y > y1:
+			y1 = p.Y
+		case p.Y < y0:
+			y0 = p.Y
+		}
+	}
+	return image.Rect(x0, y0, x1, y1)
+}
+
+// Align sets drawing area to the buffer's bound
+func (b *Buffer) Align() {
+	b.Area = b.Bounds()
+}
+
+// NewCell returns a new cell
+func NewCell(ch rune, fg, bg Attribute) Cell {
+	return Cell{ch, fg, bg}
+}
+
+// Union squeezes buf into b
+func (b Buffer) Union(buf Buffer) {
+	for p, c := range buf.CellMap {
+		b.Set(p.X, p.Y, c)
+	}
+}
+
+// Union returns a new Buffer formed by squeezing bufs into one Buffer
+func Union(bufs ...Buffer) Buffer {
+	buf := NewBuffer()
+	for _, b := range bufs {
+		buf.Union(b)
+	}
+	buf.Align()
+	return buf
+}
+
+// Point for adapting use, will be removed after resolving bridging.
+type Point struct {
+	X  int
+	Y  int
+	Ch rune
+	Fg Attribute
+	Bg Attribute
+}
+
+// NewBuffer returns a new Buffer
+func NewBuffer() Buffer {
+	return Buffer{CellMap: make(map[image.Point]Cell)}
+}

example/gauge.go

@@ -7,6 +7,7 @@
 package main
 
 import "github.com/gizak/termui"
+import "github.com/gizak/termui/widget"
 
 func main() {
 	err := termui.Init()
@@ -17,16 +18,23 @@ func main() {
 
 	termui.UseTheme("helloworld")
 
-	g0 := termui.NewGauge()
+	g0 := widget.NewGauge()
 	g0.Percent = 40
 	g0.Width = 50
 	g0.Height = 3
 	g0.Border.Label = "Slim Gauge"
 	g0.BarColor = termui.ColorRed
-	g0.Border.FgColor = termui.ColorWhite
+	g0.Border.Fg = termui.ColorWhite
-	g0.Border.LabelFgColor = termui.ColorCyan
+	g0.Border.LabelFgClr = termui.ColorCyan
 
-	g2 := termui.NewGauge()
+	gg := termui.NewBlock()
+	gg.Width = 50
+	gg.Height = 5
+	gg.Y = 12
+	gg.Border.Label = "TEST"
+	gg.Align()
+
+	g2 := widget.NewGauge()
 	g2.Percent = 60
 	g2.Width = 50
 	g2.Height = 3
@@ -34,9 +42,9 @@ func main() {
 	g2.Y = 3
 	g2.Border.Label = "Slim Gauge"
 	g2.BarColor = termui.ColorYellow
-	g2.Border.FgColor = termui.ColorWhite
+	g2.Border.Fg = termui.ColorWhite
 
-	g1 := termui.NewGauge()
+	g1 := widget.NewGauge()
 	g1.Percent = 30
 	g1.Width = 50
 	g1.Height = 5
@@ -44,10 +52,10 @@ func main() {
 	g1.Border.Label = "Big Gauge"
 	g1.PercentColor = termui.ColorYellow
 	g1.BarColor = termui.ColorGreen
-	g1.Border.FgColor = termui.ColorWhite
+	g1.Border.Fg = termui.ColorWhite
-	g1.Border.LabelFgColor = termui.ColorMagenta
+	g1.Border.LabelFgClr = termui.ColorMagenta
 
-	termui.Render(g0, g1, g2)
+	termui.Render(g0, g1, g2, gg)
 
 	<-termui.EventCh()
 }

gauge.go

@@ -1,83 +0,0 @@
-// 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 "strconv"
-
-// Gauge is a progress bar like widget.
-// A simple example:
-/*
-  g := termui.NewGauge()
-  g.Percent = 40
-  g.Width = 50
-  g.Height = 3
-  g.Border.Label = "Slim Gauge"
-  g.BarColor = termui.ColorRed
-  g.PercentColor = termui.ColorBlue
-*/
-type Gauge struct {
-	Block
-	Percent      int
-	BarColor     Attribute
-	PercentColor Attribute
-}
-
-// NewGauge return a new gauge with current theme.
-func NewGauge() *Gauge {
-	g := &Gauge{
-		Block:        *NewBlock(),
-		PercentColor: theme.GaugePercent,
-		BarColor:     theme.GaugeBar}
-	g.Width = 12
-	g.Height = 5
-	return g
-}
-
-// Buffer implements Bufferer interface.
-func (g *Gauge) Buffer() []Point {
-	ps := g.Block.Buffer()
-
-	w := g.Percent * g.innerWidth / 100
-	s := strconv.Itoa(g.Percent) + "%"
-	rs := str2runes(s)
-
-	prx := g.innerX + g.innerWidth/2 - 1
-	pry := g.innerY + g.innerHeight/2
-
-	// plot bar
-	for i := 0; i < g.innerHeight; i++ {
-		for j := 0; j < w; j++ {
-			p := Point{}
-			p.X = g.innerX + j
-			p.Y = g.innerY + i
-			p.Ch = ' '
-			p.Bg = g.BarColor
-			if p.Bg == ColorDefault {
-				p.Bg |= AttrReverse
-			}
-			ps = append(ps, p)
-		}
-	}
-
-	// plot percentage
-	for i, v := range rs {
-		p := Point{}
-		p.X = prx + i
-		p.Y = pry
-		p.Ch = v
-		p.Fg = g.PercentColor
-		if w > g.innerWidth/2-1+i {
-			p.Bg = g.BarColor
-			if p.Bg == ColorDefault {
-				p.Bg |= AttrReverse
-			}
-
-		} else {
-			p.Bg = g.Block.BgColor
-		}
-		ps = append(ps, p)
-	}
-	return g.Block.chopOverflow(ps)
-}

grid.go

@@ -160,8 +160,8 @@ func (r *Row) SetWidth(w int) {
 
 // Buffer implements Bufferer interface,
 // recursively merge all widgets buffer
-func (r *Row) Buffer() []Point {
+func (r *Row) Buffer() Buffer {
-	merged := []Point{}
+	merged := Buffer{}
 
 	if r.isRenderableLeaf() {
 		return r.Widget.Buffer()
@@ -169,13 +169,13 @@ func (r *Row) Buffer() []Point {
 
 	// for those are not leaves but have a renderable widget
 	if r.Widget != nil {
-		merged = append(merged, r.Widget.Buffer()...)
+		merged.Union(r.Widget.Buffer())
 	}
 
 	// collect buffer from children
 	if !r.isLeaf() {
 		for _, c := range r.Cols {
-			merged = append(merged, c.Buffer()...)
+			merged.Union(c.Buffer())
 		}
 	}
 
@@ -267,12 +267,13 @@ func (g *Grid) Align() {
 }
 
 // Buffer implments Bufferer interface.
-func (g Grid) Buffer() []Point {
+func (g Grid) Buffer() Buffer {
-	ps := []Point{}
+	buf := Buffer{}
+
 	for _, r := range g.Rows {
-		ps = append(ps, r.Buffer()...)
+		buf.Union(r.Buffer())
 	}
-	return ps
+	return buf
 }
 
 // Body corresponds to the entire terminal display region.

helper.go

@@ -148,3 +148,60 @@ func StringToAttribute(text string) Attribute {
 
 	return result
 }
+
+// TextCells returns a coloured text cells []Cell
+func TextCells(s string, fg, bg Attribute) []Cell {
+	cs := make([]Cell, 0, len(s))
+
+	// sequence := MarkdownTextRendererFactory{}.TextRenderer(s).Render(fg, bg)
+	// runes := []rune(sequence.NormalizedText)
+	runes := str2runes(s)
+
+	for n := range runes {
+		// point, _ := sequence.PointAt(n, 0, 0)
+		// cs = append(cs, Cell{point.Ch, point.Fg, point.Bg})
+		cs = append(cs, Cell{runes[n], fg, bg})
+	}
+	return cs
+}
+
+// Width returns the actual screen space the cell takes (usually 1 or 2).
+func (c Cell) Width() int {
+	return charWidth(c.Ch)
+}
+
+// Copy return a copy of c
+func (c Cell) Copy() Cell {
+	return c
+}
+
+// TrimTxCells trims the overflowed text cells sequence.
+func TrimTxCells(cs []Cell, w int) []Cell {
+	if len(cs) <= w {
+		return cs
+	}
+	return cs[:w]
+}
+
+// DTrimTxCls trims the overflowed text cells sequence and append dots at the end.
+func DTrimTxCls(cs []Cell, w int) []Cell {
+	l := len(cs)
+	if l <= 0 {
+		return []Cell{}
+	}
+
+	rt := make([]Cell, 0, w)
+	csw := 0
+	for i := 0; i < l && csw <= w; i++ {
+		c := cs[i]
+		cw := c.Width()
+
+		if cw+csw <= w {
+			rt = append(rt, c)
+		} else {
+			rt = append(rt, Cell{'…', c.Fg, c.Bg})
+		}
+	}
+
+	return rt
+}

point.go

@@ -1,28 +0,0 @@
-// 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
-
-// Point stands for a single cell in terminal.
-type Point struct {
-	Ch rune
-	Bg Attribute
-	Fg Attribute
-	X  int
-	Y  int
-}
-
-func newPoint(c rune, x, y int) (p Point) {
-	p.Ch = c
-	p.X = x
-	p.Y = y
-	return
-}
-
-func newPointWithAttrs(c rune, x, y int, fg, bg Attribute) Point {
-	p := newPoint(c, x, y)
-	p.Bg = bg
-	p.Fg = fg
-	return p
-}

render.go

@@ -8,7 +8,7 @@ import tm "github.com/nsf/termbox-go"
 
 // Bufferer should be implemented by all renderable components.
 type Bufferer interface {
-	Buffer() []Point
+	Buffer() Buffer
 }
 
 // Init initializes termui library. This function should be called before any others.
@@ -46,13 +46,18 @@ func TermHeight() int {
 
 // Render renders all Bufferer in the given order from left to right,
 // right could overlap on left ones.
-func Render(rs ...Bufferer) {
+func Render(bs ...Bufferer) {
+	// set tm bg
 	tm.Clear(tm.ColorDefault, toTmAttr(theme.BodyBg))
-	for _, r := range rs {
+	for _, b := range bs {
-		buf := r.Buffer()
+		buf := b.Buffer()
-		for _, v := range buf {
+		// set cels in buf
-			tm.SetCell(v.X, v.Y, v.Ch, toTmAttr(v.Fg), toTmAttr(v.Bg))
+		for p, c := range buf.CellMap {
+			if true { //}p.In(buf.Area) {
+				tm.SetCell(p.X, p.Y, c.Ch, toTmAttr(c.Fg), toTmAttr(c.Bg))
+			}
 		}
 	}
+	// render
 	tm.Flush()
 }

textRender.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 package termui
 
 import (

widget/barchart.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/canvas.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/canvas_test.go

@@ -1,3 +1,5 @@
+//+build ignore
+
 package termui
 
 import (

widget/gauge.go

@@ -0,0 +1,67 @@
+// 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 widget
+
+import "github.com/gizak/termui"
+import "strconv"
+
+// Gauge is a progress bar like widget.
+// A simple example:
+/*
+  g := termui.NewGauge()
+  g.Percent = 40
+  g.Width = 50
+  g.Height = 3
+  g.Border.Label = "Slim Gauge"
+  g.BarColor = termui.ColorRed
+  g.PercentColor = termui.ColorBlue
+*/
+type Gauge struct {
+	termui.Block
+	Percent      int
+	BarColor     termui.Attribute
+	PercentColor termui.Attribute
+}
+
+// NewGauge return a new gauge with current theme.
+func NewGauge() *Gauge {
+	g := &Gauge{
+		Block:        *termui.NewBlock(),
+		PercentColor: termui.Theme().GaugePercent,
+		BarColor:     termui.Theme().GaugeBar}
+	g.Width = 12
+	g.Height = 3
+	return g
+}
+
+// Buffer implements Bufferer interface.
+func (g *Gauge) Buffer() termui.Buffer {
+	buf := g.Block.Buffer()
+
+	inner := g.InnerBounds()
+	w := g.Percent * (inner.Dx() + 1) / 100
+	s := strconv.Itoa(g.Percent) + "%"
+	tx := termui.TextCells(s, g.PercentColor, g.Bg)
+
+	prx := inner.Min.X + (inner.Dx()+1)/2 - 1
+	pry := inner.Min.Y + (inner.Dy()+1)/2
+
+	// plot bar
+	for i := 0; i <= inner.Dy(); i++ {
+		for j := 0; j < w; j++ {
+			c := termui.Cell{' ', g.BarColor, g.BarColor}
+			buf.Set(inner.Min.X+j, inner.Min.Y+i, c)
+		}
+	}
+
+	// plot percentage
+	for i, v := range tx {
+		if w > (inner.Dx()+1)/2-1+i {
+			v.Bg = g.BarColor
+		}
+		buf.Set(prx+i, pry, v)
+	}
+	return buf
+}

widget/linechart.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/linechart_others.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/linechart_windows.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/list.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/par.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.

widget/sparkline.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 // 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.