plot: add some comments

Plot.go

@@ -184,6 +184,7 @@ func (p *PlotCanvasWidget) Build() {
 	}
 }
 
+// PlotBarWidget adds bar plot (column chart) to the canvas
 type PlotBarWidget struct {
 	title  string
 	data   []float64
@@ -192,6 +193,7 @@ type PlotBarWidget struct {
 	offset int
 }
 
+// PlotBar adds a plot bar (column chart)
 func PlotBar(title string, data []float64) *PlotBarWidget {
 	return &PlotBarWidget{
 		title:  title,
@@ -202,25 +204,30 @@ func PlotBar(title string, data []float64) *PlotBarWidget {
 	}
 }
 
+// Width sets bar width
 func (p *PlotBarWidget) Width(width float64) *PlotBarWidget {
 	p.width = width
 	return p
 }
 
+// Shift sets shift of the bar
 func (p *PlotBarWidget) Shift(shift float64) *PlotBarWidget {
 	p.shift = shift
 	return p
 }
 
+// Offset sets bar's offset
 func (p *PlotBarWidget) Offset(offset int) *PlotBarWidget {
 	p.offset = offset
 	return p
 }
 
+// Plot implements Plot interface
 func (p *PlotBarWidget) Plot() {
 	imgui.ImPlotBars(p.title, p.data, p.width, p.shift, p.offset)
 }
 
+// PlotBarHWidget represents a column chart on Y axis
 type PlotBarHWidget struct {
 	title  string
 	data   []float64
@@ -229,6 +236,7 @@ type PlotBarHWidget struct {
 	offset int
 }
 
+// PlotBarH adds plot bars on y axis
 func PlotBarH(title string, data []float64) *PlotBarHWidget {
 	return &PlotBarHWidget{
 		title:  title,
@@ -239,25 +247,30 @@ func PlotBarH(title string, data []float64) *PlotBarHWidget {
 	}
 }
 
+// Height sets bar height (in fact bars' width)
 func (p *PlotBarHWidget) Height(height float64) *PlotBarHWidget {
 	p.height = height
 	return p
 }
 
+// Shift sets shift
 func (p *PlotBarHWidget) Shift(shift float64) *PlotBarHWidget {
 	p.shift = shift
 	return p
 }
 
+// Offset sets offset
 func (p *PlotBarHWidget) Offset(offset int) *PlotBarHWidget {
 	p.offset = offset
 	return p
 }
 
+// Plot implements plot interface
 func (p *PlotBarHWidget) Plot() {
 	imgui.ImPlotBarsH(tStr(p.title), p.data, p.height, p.shift, p.offset)
 }
 
+// PlotLineWidget represents a plot line (linear chart)
 type PlotLineWidget struct {
 	title      string
 	values     []float64
@@ -266,6 +279,7 @@ type PlotLineWidget struct {
 	yAxis      ImPlotYAxis
 }
 
+// PlotLine adds a new plot line to the canvas
 func PlotLine(title string, values []float64) *PlotLineWidget {
 	return &PlotLineWidget{
 		title:  title,
@@ -276,37 +290,44 @@ func PlotLine(title string, values []float64) *PlotLineWidget {
 	}
 }
 
+// SetPlotYAxis sets yAxis parameters
 func (p *PlotLineWidget) SetPlotYAxis(yAxis ImPlotYAxis) *PlotLineWidget {
 	p.yAxis = yAxis
 	return p
 }
 
+// XScale sets x-axis-scale
 func (p *PlotLineWidget) XScale(scale float64) *PlotLineWidget {
 	p.xScale = scale
 	return p
 }
 
+// X0 sets a start position on x axis
 func (p *PlotLineWidget) X0(x0 float64) *PlotLineWidget {
 	p.x0 = x0
 	return p
 }
 
+// Offset sets chart offset
 func (p *PlotLineWidget) Offset(offset int) *PlotLineWidget {
 	p.offset = offset
 	return p
 }
 
+// Plot implements Plot interface
 func (p *PlotLineWidget) Plot() {
 	imgui.ImPlotSetPlotYAxis(imgui.ImPlotYAxis(p.yAxis))
 	imgui.ImPlotLine(tStr(p.title), p.values, p.xScale, p.x0, p.offset)
 }
 
+// PlotLineXYWidget adds XY plot line
 type PlotLineXYWidget struct {
 	title  string
 	xs, ys []float64
 	offset int
 }
 
+// PlotLineXY adds XY plot line to canvas
 func PlotLineXY(title string, xvalues, yvalues []float64) *PlotLineXYWidget {
 	return &PlotLineXYWidget{
 		title:  title,
@@ -316,15 +337,18 @@ func PlotLineXY(title string, xvalues, yvalues []float64) *PlotLineXYWidget {
 	}
 }
 
+// Offset sets chart's offset
 func (p *PlotLineXYWidget) Offset(offset int) *PlotLineXYWidget {
 	p.offset = offset
 	return p
 }
 
+// Plot implements Plot interface
 func (p *PlotLineXYWidget) Plot() {
 	imgui.ImPlotLineXY(tStr(p.title), p.xs, p.ys, p.offset)
 }
 
+// PlotPieChartWidget represents a pie chart
 type PlotPieChartWidget struct {
 	labels       []string
 	values       []float64
@@ -334,6 +358,7 @@ type PlotPieChartWidget struct {
 	angle0       float64
 }
 
+// PlotPieChart adds pie chart to the canvas
 func PlotPieChart(labels []string, values []float64, x, y, radius float64) *PlotPieChartWidget {
 	return &PlotPieChartWidget{
 		labels:      labels,
@@ -352,6 +377,7 @@ func (p *PlotPieChartWidget) Normalize(n bool) *PlotPieChartWidget {
 	return p
 }
 
+// LabelFormat sets format of labels
 func (p *PlotPieChartWidget) LabelFormat(fmtStr string) *PlotPieChartWidget {
 	p.labelFormat = fmtStr
 	return p