yaxis.go

package charts

type YAxisOption struct {
	// Show specifies if the y-axis should be rendered, set this to *false (through False()) to hide the axis.
	Show *bool
	// Theme specifies the colors used for the x-axis.
	Theme ColorPalette
	// Color for y-axis.
	AxisColor Color
	// Min, if set this will force the minimum value of y-axis.
	Min *float64
	// Max, if set this will force the maximum value of y-axis.
	Max *float64
	// RangeValuePaddingScale suggest a scale of padding added to the max and min values.
	RangeValuePaddingScale *float64
	// Data provides labels for the y-axis.
	Data []string
	// Position describes the position of y-axis, it can be 'left' or 'right'.
	Position string
	// FontStyle specifies the font configuration for each label.
	FontStyle FontStyle
	// Formatter for replacing y-axis text values.
	Formatter string
	// Unit is a suggestion for how large the axis step is, this is a recommendation only. Larger numbers result in fewer labels.
	Unit float64
	// LabelCount is the number of labels to show on the axis. Specify a smaller number to reduce writing collisions.
	LabelCount int
	// LabelCountAdjustment specifies a relative influence on how many labels should be rendered.
	// Typically, this is negative to result in cleaner graphs, positive values may result in text collisions.
	LabelCountAdjustment int
	// LabelSkipCount specifies a number of lines between labels where there will be no label and instead just a horizontal line.
	LabelSkipCount int
	isCategoryAxis bool
	// SplitLineShow for showing axis split line, set this to true to show the horizontal axis split lines.
	SplitLineShow *bool
	// SpineLineShow can be set to enforce if the vertical spine on the axis should be shown or not.
	// By default, not shown unless a category axis.
	SpineLineShow *bool
	// ValueFormatter defines how float values should be rendered to strings, notably for numeric axis labels.
	ValueFormatter ValueFormatter
}

func (opt *YAxisOption) toAxisOption(fallbackTheme ColorPalette) axisOption {
	position := PositionLeft
	if opt.Position == PositionRight {
		position = PositionRight
	}
	theme := getPreferredTheme(opt.Theme, fallbackTheme)
	axisOpt := axisOption{
		Formatter:            opt.Formatter,
		Theme:                theme,
		Data:                 opt.Data,
		Position:             position,
		FontStyle:            opt.FontStyle,
		StrokeWidth:          -1,
		BoundaryGap:          False(),
		Unit:                 opt.Unit,
		LabelCount:           opt.LabelCount,
		LabelCountAdjustment: opt.LabelCountAdjustment,
		LabelSkipCount:       opt.LabelSkipCount,
		SplitLineShow:        true,
		Show:                 opt.Show,
	}
	if !opt.AxisColor.IsZero() {
		if axisOpt.FontStyle.FontColor.IsZero() {
			axisOpt.FontStyle.FontColor = opt.AxisColor
		}
		axisOpt.Theme = theme.WithAxisColor(opt.AxisColor)
	}
	if opt.isCategoryAxis {
		axisOpt.BoundaryGap = True()
		axisOpt.StrokeWidth = 1
		axisOpt.SplitLineShow = false
	}
	if opt.SplitLineShow != nil {
		axisOpt.SplitLineShow = *opt.SplitLineShow
	}
	if opt.SpineLineShow != nil {
		if *opt.SpineLineShow {
			axisOpt.StrokeWidth = 1
		} else {
			axisOpt.StrokeWidth = -1
		}
	}
	return axisOpt
}

// newLeftYAxis returns a left y-axis renderer.
func newLeftYAxis(p *Painter, opt YAxisOption) *axisPainter {
	p = p.Child(PainterPaddingOption(Box{
		Bottom: defaultXAxisHeight,
	}))
	return newAxisPainter(p, opt.toAxisOption(p.theme))
}

// newRightYAxis returns a right y-axis renderer.
func newRightYAxis(p *Painter, opt YAxisOption) *axisPainter {
	p = p.Child(PainterPaddingOption(Box{
		Bottom: defaultXAxisHeight,
	}))
	axisOpt := opt.toAxisOption(p.theme)
	axisOpt.Position = PositionRight
	axisOpt.SplitLineShow = false
	return newAxisPainter(p, axisOpt)
}