A stroke_style describes how the lines of a graphical are drawn,
beyond their thickness (graphical<-pen)
and colour. It is used as the graphical<-texture,
in place of one of the texture names such as dashed. One
stroke_style may be shared by many graphicals.
new(S, stroke_style(round, round, vector(8, 4))),
send(Path, pen, 3),
send(Path, texture, S).
Using a gradient as stroke_style<-paint,
a line can change colour along its length:
new(G, gradient(linear, point(0,0), point(200,0))),
send(G, add_stop, 0, colour(red)),
send(G, add_stop, 1, colour(blue)),
send(Line, texture, stroke_style(paint := G)).
Round and square caps and miter joins make a line cover more than the
area spanned by its points. Class line
and class path take
this into account when computing their area.
- stroke_style <->
cap: {butt,round,square}
- Shape of the ends of a line.
butt ends at the end point, round
and square extend half the pen beyond it.
Defaults: butt
- stroke_style <->
join: {miter,round,bevel}
- Shape of the corners of a line.
Defaults: miter
- stroke_style <->
miter_limit: num
- Miter joins whose tip is more than this times the pen away from the
corner are drawn as bevel joins, to avoid long spikes at sharp corners.
Defaults: 10
- stroke_style <-
dash: texture_name
|vector* - Either the name of a dash pattern as accepted by
graphical
<-texture
or a vector of numbers holding the lengths of alternating dashes and
gaps. @nil
draws a solid line.
Defaults: @nil
- stroke_style <->
dash_offset: num
- Distance into the dash pattern at the start of the line.
Defaults: 0
- stroke_style <->
paint: colour
|gradient* - Paint used for the line. If @nil,
the line is drawn using
graphical
<-colour.
The paint is ignored for an inactive graphical, which is drawn in its
inactive colour.
Defaults: @nil
- stroke_style ->initialise: cap=[{butt,round,square}],
join=[{miter,round,bevel}], dash=[texture_name
|vector*],
paint=[colour|gradient*] - Create a stroke style.
