Line symbolizer

The line symbolizer is used to style linear (1-dimensional) features. It is in some ways the simplest of the symbolizers because it only contains facilities for the stroke (outline) of a feature.

Syntax

The full syntax of a line symbolizer is:

symbolizers:
- line:
    stroke-color: <color>
    stroke-width: <expression>
    stroke-opacity: <expression>
    stroke-linejoin: <expression>
    stroke-linecap: <expression>
    stroke-dasharray: <float list>
    stroke-dashoffset: <expression>
    stroke-graphic: 
      <graphic_options>
    stroke-graphic-fill: 
      <graphic_options>
    offset: <expression>
    geometry: <expression>
    uom: <text>
    x-labelObstacle: <boolean>
    x-composite-base: <boolean>
    x-composite: <text>
    x-inclusion: <text>

where:

{% include-markdown "./include/stroke.md" %}

• • Property
  • Required?
  • Description
  • Default value
• • offset
  • No
  • Value in pixels for moving the drawn line relative to the location of the feature.
  • 0

{% include-markdown "./include/symbol.md" %}

{% include-markdown "./include/misc.md" %}

{% include-markdown "./include/composite.md" %}

{% include-markdown "./include/inclusion.md" %}

Examples

Basic line with styled ends

The linejoin and linecap properties can be used to style the joins and ends of any stroke. This example draws lines with partially transparent black lines with rounded ends and sharp (mitred) corners:

feature-styles:
- rules:
  - symbolizers:
    - line:
        stroke-color: '#000000'
        stroke-width: 8
        stroke-opacity: 0.5
        stroke-linejoin: mitre
        stroke-linecap: round

Basic line with styled ends

Railroad pattern

Todo

Fix this example

Many maps use a hatched pattern to represent railroads. This can be accomplished by using two line symbolizers, one solid and one dashed. Specifically, the stroke-dasharray property is used to create a dashed line of length 1 every 24 pixels:

name: railroad
feature-styles:
- name: name
  rules:
  - symbolizers:
    - line:
        stroke-color: '#000000'
        stroke-width: 1
    - line:
        stroke-color: '#000000'
        stroke-width: 12
        stroke-dasharray: '1 24'

Railroad pattern

Specifying sizes in units

The units for stroke-width, size, and other similar attributes default to pixels, meaning that graphics remain a constant size at different zoom levels. Alternately, units (feet or meters) can be specified for values, so graphics will scale as you zoom in or out. This example draws roads with a fixed width of 8 meters:

feature-styles:
- rules:
  - symbolizers:
    - line:
        stroke-color: '#000000'
        stroke-width: '8 m'

Line width measured in meters (zoomed out)

Line width measured in meters (zoomed in)

The default unit of measure for the symbolizer is defined using uom. This example uses a default of meters to supply distances for stroke-width and stroke-dasharray using meters.

line:
  uom: metre
  stroke-color: '#000000'
  stroke-width: '8'
  stroke-dasharray: '20 3'

Line width and spacing in meters