Mojo struct 🡭

LineStyle

@memory_only
struct LineStyle

How a stroke is broken up along its length, set via Theme.gridline_style/Theme.annotation_line_style or Plot.mark_line(style=...).

A dash pattern is not decoration. A reference line and a fitted trend are not data, and dashing them is the conventional way of saying so – a solid annotate_hline reads as another series. It also distinguishes series without relying on hue, which matters for print and for readers who cannot separate the palette’s colors.

The patterns are in multiples of the stroke’s own scale rather than absolute pixels, so a dash looks the same at any Theme.scale; see dashes().

Aliases

• SOLID = LineStyle(Int(0)): An unbroken stroke. The default, and what every line drew before this setting existed.
• DASHED = LineStyle(Int(1)): Long dashes with gaps a little shorter – the usual “this is a threshold, not a measurement” line.
• DOTTED = LineStyle(Int(2)): Round-ish dots at a tight spacing, for a line that should stay legible without competing with the data. The usual choice for gridlines.
• DASH_DOT = LineStyle(Int(3)): Alternating long dash and dot, for when a chart already uses both DASHED and DOTTED and needs a third.

Implemented traits

AnyType, Copyable, Deinitable, ImplicitlyCopyable, Movable

Methods

__init__

fn def __init__(out self, value: Int)

Prefer the SOLID/DASHED/DOTTED/DASH_DOT comptime constants over constructing one directly.

Args:

• value (Int): 0 for SOLID, 1 for DASHED, 2 for DOTTED, 3 for DASH_DOT.
• self (Self)

Returns:

Self

__eq__

fn def __eq__(self, other: Self) -> Bool

Args:

• self (Self)
• other (Self)

Returns:

Bool

__ne__

fn def __ne__(self, other: Self) -> Bool

Args:

• self (Self)
• other (Self)

Returns:

Bool

dashes

fn def dashes(self, scale: Float64) -> List[Float64]

The on/off lengths canvas’s dashes= wants, in pixels.

Multiplied by scale – pass _Scaled.scale, the same factor every other piece of furniture is sized by – so a dash keeps its proportions when Theme.scale changes. A pattern in fixed pixels would turn into a nearly solid line on a dense chart and a row of specks on a sparse one.

SOLID returns an empty list, which is what canvas reads as “no dashing”, so a caller can pass the result unconditionally.

Args:

• self (Self)
• scale (Float64): The theme’s scale factor.

Returns:

List[Float64]: On/off lengths, empty for SOLID.