gatus/golang-github-wcharczuk-go-chart
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Adding upstream version 2.1.2.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-05-18 07:17:02 +02:00
parent c8c64afc61
commit 41a2f19f12
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
220 changed files with 19814 additions and 0 deletions
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donut_chart.go Normal file
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package chart
import (
"errors"
"fmt"
"io"
"github.com/golang/freetype/truetype"
)
// DonutChart is a chart that draws sections of a circle based on percentages with an hole.
type DonutChart struct {
Title string
TitleStyle Style
ColorPalette ColorPalette
Width int
Height int
DPI float64
Background Style
Canvas Style
SliceStyle Style
Font *truetype.Font
defaultFont *truetype.Font
Values []Value
Elements []Renderable
}
// GetDPI returns the dpi for the chart.
func (pc DonutChart) GetDPI(defaults ...float64) float64 {
if pc.DPI == 0 {
if len(defaults) > 0 {
return defaults[0]
}
return DefaultDPI
}
return pc.DPI
}
// GetFont returns the text font.
func (pc DonutChart) GetFont() *truetype.Font {
if pc.Font == nil {
return pc.defaultFont
}
return pc.Font
}
// GetWidth returns the chart width or the default value.
func (pc DonutChart) GetWidth() int {
if pc.Width == 0 {
return DefaultChartWidth
}
return pc.Width
}
// GetHeight returns the chart height or the default value.
func (pc DonutChart) GetHeight() int {
if pc.Height == 0 {
return DefaultChartWidth
}
return pc.Height
}
// Render renders the chart with the given renderer to the given io.Writer.
func (pc DonutChart) Render(rp RendererProvider, w io.Writer) error {
if len(pc.Values) == 0 {
return errors.New("please provide at least one value")
}
r, err := rp(pc.GetWidth(), pc.GetHeight())
if err != nil {
return err
}
if pc.Font == nil {
defaultFont, err := GetDefaultFont()
if err != nil {
return err
}
pc.defaultFont = defaultFont
}
r.SetDPI(pc.GetDPI(DefaultDPI))
canvasBox := pc.getDefaultCanvasBox()
canvasBox = pc.getCircleAdjustedCanvasBox(canvasBox)
pc.drawBackground(r)
pc.drawCanvas(r, canvasBox)
finalValues, err := pc.finalizeValues(pc.Values)
if err != nil {
return err
}
pc.drawSlices(r, canvasBox, finalValues)
pc.drawTitle(r)
for _, a := range pc.Elements {
a(r, canvasBox, pc.styleDefaultsElements())
}
return r.Save(w)
}
func (pc DonutChart) drawBackground(r Renderer) {
Draw.Box(r, Box{
Right: pc.GetWidth(),
Bottom: pc.GetHeight(),
}, pc.getBackgroundStyle())
}
func (pc DonutChart) drawCanvas(r Renderer, canvasBox Box) {
Draw.Box(r, canvasBox, pc.getCanvasStyle())
}
func (pc DonutChart) drawTitle(r Renderer) {
if len(pc.Title) > 0 && !pc.TitleStyle.Hidden {
Draw.TextWithin(r, pc.Title, pc.Box(), pc.styleDefaultsTitle())
}
}
func (pc DonutChart) drawSlices(r Renderer, canvasBox Box, values []Value) {
cx, cy := canvasBox.Center()
diameter := MinInt(canvasBox.Width(), canvasBox.Height())
radius := float64(diameter>>1) / 1.1
labelRadius := (radius * 2.83) / 3.0
// draw the donut slices
var rads, delta, delta2, total float64
var lx, ly int
if len(values) == 1 {
pc.styleDonutChartValue(0).WriteToRenderer(r)
r.MoveTo(cx, cy)
r.Circle(radius, cx, cy)
} else {
for index, v := range values {
v.Style.InheritFrom(pc.styleDonutChartValue(index)).WriteToRenderer(r)
r.MoveTo(cx, cy)
rads = PercentToRadians(total)
delta = PercentToRadians(v.Value)
r.ArcTo(cx, cy, (radius / 1.25), (radius / 1.25), rads, delta)
r.LineTo(cx, cy)
r.Close()
r.FillStroke()
total = total + v.Value
}
}
//making the donut hole
v := Value{Value: 100, Label: "center"}
styletemp := pc.SliceStyle.InheritFrom(Style{
StrokeColor: ColorWhite, StrokeWidth: 4.0, FillColor: ColorWhite, FontColor: ColorWhite, //Font: pc.GetFont(),//FontSize: pc.getScaledFontSize(),
})
v.Style.InheritFrom(styletemp).WriteToRenderer(r)
r.MoveTo(cx, cy)
r.ArcTo(cx, cy, (radius / 3.5), (radius / 3.5), DegreesToRadians(0), DegreesToRadians(359))
r.LineTo(cx, cy)
r.Close()
r.FillStroke()
// draw the labels
total = 0
for index, v := range values {
v.Style.InheritFrom(pc.styleDonutChartValue(index)).WriteToRenderer(r)
if len(v.Label) > 0 {
delta2 = PercentToRadians(total + (v.Value / 2.0))
delta2 = RadianAdd(delta2, _pi2)
lx, ly = CirclePoint(cx, cy, labelRadius, delta2)
tb := r.MeasureText(v.Label)
lx = lx - (tb.Width() >> 1)
ly = ly + (tb.Height() >> 1)
r.Text(v.Label, lx, ly)
}
total = total + v.Value
}
}
func (pc DonutChart) finalizeValues(values []Value) ([]Value, error) {
finalValues := Values(values).Normalize()
if len(finalValues) == 0 {
return nil, fmt.Errorf("donut chart must contain at least (1) non-zero value")
}
return finalValues, nil
}
func (pc DonutChart) getDefaultCanvasBox() Box {
return pc.Box()
}
func (pc DonutChart) getCircleAdjustedCanvasBox(canvasBox Box) Box {
circleDiameter := MinInt(canvasBox.Width(), canvasBox.Height())
square := Box{
Right: circleDiameter,
Bottom: circleDiameter,
}
return canvasBox.Fit(square)
}
func (pc DonutChart) getBackgroundStyle() Style {
return pc.Background.InheritFrom(pc.styleDefaultsBackground())
}
func (pc DonutChart) getCanvasStyle() Style {
return pc.Canvas.InheritFrom(pc.styleDefaultsCanvas())
}
func (pc DonutChart) styleDefaultsCanvas() Style {
return Style{
FillColor: pc.GetColorPalette().CanvasColor(),
StrokeColor: pc.GetColorPalette().CanvasStrokeColor(),
StrokeWidth: DefaultStrokeWidth,
}
}
func (pc DonutChart) styleDefaultsDonutChartValue() Style {
return Style{
StrokeColor: pc.GetColorPalette().TextColor(),
StrokeWidth: 4.0,
FillColor: pc.GetColorPalette().TextColor(),
}
}
func (pc DonutChart) styleDonutChartValue(index int) Style {
return pc.SliceStyle.InheritFrom(Style{
StrokeColor: ColorWhite,
StrokeWidth: 4.0,
FillColor: pc.GetColorPalette().GetSeriesColor(index),
FontSize: pc.getScaledFontSize(),
FontColor: pc.GetColorPalette().TextColor(),
Font: pc.GetFont(),
})
}
func (pc DonutChart) getScaledFontSize() float64 {
effectiveDimension := MinInt(pc.GetWidth(), pc.GetHeight())
if effectiveDimension >= 2048 {
return 48.0
} else if effectiveDimension >= 1024 {
return 24.0
} else if effectiveDimension > 512 {
return 18.0
} else if effectiveDimension > 256 {
return 12.0
}
return 10.0
}
func (pc DonutChart) styleDefaultsBackground() Style {
return Style{
FillColor: pc.GetColorPalette().BackgroundColor(),
StrokeColor: pc.GetColorPalette().BackgroundStrokeColor(),
StrokeWidth: DefaultStrokeWidth,
}
}
func (pc DonutChart) styleDefaultsElements() Style {
return Style{
Font: pc.GetFont(),
}
}
func (pc DonutChart) styleDefaultsTitle() Style {
return pc.TitleStyle.InheritFrom(Style{
FontColor: pc.GetColorPalette().TextColor(),
Font: pc.GetFont(),
FontSize: pc.getTitleFontSize(),
TextHorizontalAlign: TextHorizontalAlignCenter,
TextVerticalAlign: TextVerticalAlignTop,
TextWrap: TextWrapWord,
})
}
func (pc DonutChart) getTitleFontSize() float64 {
effectiveDimension := MinInt(pc.GetWidth(), pc.GetHeight())
if effectiveDimension >= 2048 {
return 48
} else if effectiveDimension >= 1024 {
return 24
} else if effectiveDimension >= 512 {
return 18
} else if effectiveDimension >= 256 {
return 12
}
return 10
}
// GetColorPalette returns the color palette for the chart.
func (pc DonutChart) GetColorPalette() ColorPalette {
if pc.ColorPalette != nil {
return pc.ColorPalette
}
return AlternateColorPalette
}
// Box returns the chart bounds as a box.
func (pc DonutChart) Box() Box {
dpr := pc.Background.Padding.GetRight(DefaultBackgroundPadding.Right)
dpb := pc.Background.Padding.GetBottom(DefaultBackgroundPadding.Bottom)
return Box{
Top: pc.Background.Padding.GetTop(DefaultBackgroundPadding.Top),
Left: pc.Background.Padding.GetLeft(DefaultBackgroundPadding.Left),
Right: pc.GetWidth() - dpr,
Bottom: pc.GetHeight() - dpb,
}
}