go-chart/yaxis.go
Will Charczuk 8f56e5939b snapshot.
2016-09-05 13:26:12 -07:00

214 lines
5.1 KiB
Go

package chart
import (
"math"
"sort"
)
// YAxis is a veritcal rule of the range.
// There can be (2) y-axes; a primary and secondary.
type YAxis struct {
Name string
NameStyle Style
Style Style
Zero GridLine
AxisType YAxisType
ValueFormatter ValueFormatter
Range Range
TickStyle Style
Ticks []Tick
GridLines []GridLine
GridMajorStyle Style
GridMinorStyle Style
}
// GetName returns the name.
func (ya YAxis) GetName() string {
return ya.Name
}
// GetNameStyle returns the name style.
func (ya YAxis) GetNameStyle() Style {
return ya.NameStyle
}
// GetStyle returns the style.
func (ya YAxis) GetStyle() Style {
return ya.Style
}
// GetTickStyle returns the tick style.
func (ya YAxis) GetTickStyle() Style {
return ya.TickStyle
}
// GetTicks returns the ticks for a series.
// The coalesce priority is:
// - User Supplied Ticks (i.e. Ticks array on the axis itself).
// - Range ticks (i.e. if the range provides ticks).
// - Generating continuous ticks based on minimum spacing and canvas width.
func (ya YAxis) GetTicks(r Renderer, ra Range, defaults Style, vf ValueFormatter) []Tick {
if len(ya.Ticks) > 0 {
return ya.Ticks
}
if tp, isTickProvider := ra.(TicksProvider); isTickProvider {
return tp.GetTicks(r, defaults, vf)
}
tickStyle := ya.Style.InheritFrom(defaults)
return GenerateContinuousTicks(r, ra, true, tickStyle, vf)
}
// GetGridLines returns the gridlines for the axis.
func (ya YAxis) GetGridLines(ticks []Tick) []GridLine {
if len(ya.GridLines) > 0 {
return ya.GridLines
}
return GenerateGridLines(ticks, ya.GridMajorStyle, ya.GridMinorStyle)
}
// Measure returns the bounds of the axis.
func (ya YAxis) Measure(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) Box {
sort.Sort(Ticks(ticks))
var tx int
if ya.AxisType == YAxisPrimary {
tx = canvasBox.Right + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
tx = canvasBox.Left - DefaultYAxisMargin
}
ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults)).WriteToRenderer(r)
var minx, maxx, miny, maxy = math.MaxInt32, 0, math.MaxInt32, 0
var maxTextHeight int
for _, t := range ticks {
v := t.Value
ly := canvasBox.Bottom - ra.Translate(v)
tb := r.MeasureText(t.Label)
finalTextX := tx
if ya.AxisType == YAxisSecondary {
finalTextX = tx - tb.Width()
}
if tb.Height() > maxTextHeight {
maxTextHeight = tb.Height()
}
if ya.AxisType == YAxisPrimary {
minx = canvasBox.Right
maxx = Math.MaxInt(maxx, tx+tb.Width())
} else if ya.AxisType == YAxisSecondary {
minx = Math.MinInt(minx, finalTextX)
maxx = Math.MaxInt(maxx, tx)
}
miny = Math.MinInt(miny, ly-tb.Height()>>1)
maxy = Math.MaxInt(maxy, ly+tb.Height()>>1)
}
if ya.NameStyle.Show && len(ya.Name) > 0 {
maxx += (DefaultYAxisMargin + maxTextHeight)
}
return Box{
Top: miny,
Left: minx,
Right: maxx,
Bottom: maxy,
}
}
// Render renders the axis.
func (ya YAxis) Render(r Renderer, canvasBox Box, ra Range, defaults Style, ticks []Tick) {
ya.Style.InheritFrom(defaults).WriteToRenderer(r)
sort.Sort(Ticks(ticks))
sw := ya.Style.GetStrokeWidth(defaults.StrokeWidth)
var lx int
var tx int
if ya.AxisType == YAxisPrimary {
lx = canvasBox.Right + int(sw)
tx = lx + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
lx = canvasBox.Left - int(sw)
tx = lx - DefaultYAxisMargin
}
r.MoveTo(lx, canvasBox.Bottom)
r.LineTo(lx, canvasBox.Top)
r.Stroke()
var maxTextWidth int
for _, t := range ticks {
ya.TickStyle.InheritFrom(ya.Style.InheritFrom(defaults)).WriteToRenderer(r)
v := t.Value
ly := canvasBox.Bottom - ra.Translate(v)
tb := r.MeasureText(t.Label)
if tb.Width() > maxTextWidth {
maxTextWidth = tb.Width()
}
finalTextX := tx
finalTextY := ly + tb.Height()>>1
if ya.AxisType == YAxisSecondary {
finalTextX = tx - tb.Width()
}
r.Text(t.Label, finalTextX, finalTextY)
ya.Style.InheritFrom(defaults).WriteToRenderer(r)
r.MoveTo(lx, ly)
if ya.AxisType == YAxisPrimary {
r.LineTo(lx+DefaultHorizontalTickWidth, ly)
} else if ya.AxisType == YAxisSecondary {
r.LineTo(lx-DefaultHorizontalTickWidth, ly)
}
r.Stroke()
}
nameStyle := ya.NameStyle.InheritFrom(defaults.InheritFrom(Style{TextRotationDegrees: 90}))
if ya.NameStyle.Show && len(ya.Name) > 0 {
nameStyle.GetTextOptions().WriteToRenderer(r)
tb := r.MeasureText(ya.Name)
var tx int
if ya.AxisType == YAxisPrimary {
tx = canvasBox.Right + int(sw) + DefaultYAxisMargin + maxTextWidth + DefaultYAxisMargin
} else if ya.AxisType == YAxisSecondary {
tx = canvasBox.Left - (DefaultYAxisMargin + int(sw) + maxTextWidth + DefaultYAxisMargin)
}
ty := canvasBox.Bottom - (canvasBox.Height()>>1 + tb.Width()>>1)
r.Text(ya.Name, tx, ty)
}
if ya.Zero.Style.Show {
ya.Zero.Render(r, canvasBox, ra, false, Style{})
}
if ya.GridMajorStyle.Show || ya.GridMinorStyle.Show {
for _, gl := range ya.GetGridLines(ticks) {
if (gl.IsMinor && ya.GridMinorStyle.Show) || (!gl.IsMinor && ya.GridMajorStyle.Show) {
defaults := ya.GridMajorStyle
if gl.IsMinor {
defaults = ya.GridMinorStyle
}
gl.Render(r, canvasBox, ra, false, gl.Style.InheritFrom(defaults))
}
}
}
}