LineSymbolizer

LineSymbolizer

A LineSymbolizer is used to render a "stroke" along a linear geometry.

|| parameter || value || description || unit || default || || stroke || CSS colour || A Color value such as 'green' or #A3D979 || - || "black" || || stroke-width || 0.0 - n || Width of line || pixels || 1.0 || || stroke-opacity || 0.0 - 1.0 || 1 is fully opaque while zero is fully transparent and .5 would be 50% transparent|| transparency || 1.0 || || stroke-linejoin || miter, round, bevel || See http://www.w3.org/TR/SVG/painting.html#propdef-stroke-linejoin for an example for each value || - || miter || || stroke-linecap || round, butt, square || See http://www.w3.org/TR/SVG/painting.html#propdef-stroke-linecap for an example for each value || - || butt || || stroke-dasharray || 0.0 - n,0.0 - n || A pair of length values [a,b], where (a) is the dash length and (b) is the gap length respectively. More than two values are supported as well (e.g. to start the line not with a stroke, but with a gap). || pixels || none ||

Examples

Image(htdocs:/images/line_symbolizer_2.png)

Default

BR Image(default_line_symbolizer.png)

#!xml
<LineSymbolizer />

XML

#!xml
<LineSymbolizer>
    <CssParameter name="stroke">#0000ff</CssParameter>
    <CssParameter name="stroke-width">4</CssParameter>
</LineSymbolizer>

Python

#!python
l = LineSymbolizer(Color('green'),0.1)
l.stroke.add_dash(.1,.1)
l.stroke.opacity = .5

Fetch all the possible methods like:

#!python
>>> from mapnik import LineSymbolizer
>>> dir(LineSymbolizer().stroke)

C++

#!cpp
rule_type rule;
stroke ls;         // This is the line symbolizer
ls.set_color(color(255, 255, 255);
ls.set_width(4);   // width of the line in pixels
ls.set_line_join(mapnik::ROUND_JOIN);
ls.set_line_cap(mapnik::ROUND_CAP);
ls.add_dash(2.5, 1.0);
ls.set_opacity(0.5);
rule.append(ls);