{{SVGRef}}
The <marker>
SVG element defines a graphic used for drawing arrowheads or polymarkers on a given {{SVGElement("path")}}
, {{SVGElement("line")}}
, {{SVGElement("polyline")}}
or {{SVGElement("polygon")}}
element.
Markers can be attached to shapes using the {{SVGAttr("marker-start")}}
, {{SVGAttr("marker-mid")}}
, and {{SVGAttr("marker-end")}}
properties.
Examples
Drawing arrowheads
The following example shows how to draw an arrowhead on a line and on a curved path.
For the curved path, an arrowhead is drawn at each point with a {{SVGAttr("marker-mid")}}
marker.
html,
body,
svg {
height: 100%;
}
<svg viewBox="0 0 300 100" xmlns="http://www.w3.org/2000/svg">
<defs>
<!-- A marker to be used as an arrowhead -->
<marker
id="arrow"
viewBox="0 0 10 10"
refX="5"
refY="5"
markerWidth="6"
markerHeight="6"
orient="auto-start-reverse">
<path d="M 0 0 L 10 5 L 0 10 z" />
</marker>
</defs>
<!-- A line with a marker -->
<line
x1="10"
y1="10"
x2="90"
y2="90"
stroke="black"
marker-end="url(#arrow)" />
<!-- A curved path with markers -->
<path
d="M 110 10
C 120 20, 130 20, 140 10
C 150 0, 160 0, 170 10
C 180 20, 190 20, 200 10"
stroke="black"
fill="none"
marker-start="url(#arrow)"
marker-mid="url(#arrow)"
marker-end="url(#arrow)" />
</svg>
{{EmbedLiveSample('Drawing_arrowheads', 200, 200)}}
Drawing polymarkers
html,
body,
svg {
height: 100%;
}
<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg">
<defs>
<!-- Arrowhead marker definition -->
<marker
id="arrow"
viewBox="0 0 10 10"
refX="5"
refY="5"
markerWidth="6"
markerHeight="6"
orient="auto-start-reverse">
<path d="M 0 0 L 10 5 L 0 10 z" />
</marker>
<!-- Dot marker definition -->
<marker
id="dot"
viewBox="0 0 10 10"
refX="5"
refY="5"
markerWidth="5"
markerHeight="5">
<circle cx="5" cy="5" r="5" fill="red" />
</marker>
</defs>
<!-- Coordinate axes with an arrowhead in both directions -->
<polyline
points="10,10 10,90 90,90"
fill="none"
stroke="black"
marker-start="url(#arrow)"
marker-end="url(#arrow)" />
<!-- Data line with polymarkers -->
<polyline
points="15,80 29,50 43,60 57,30 71,40 85,15"
fill="none"
stroke="grey"
marker-start="url(#dot)"
marker-mid="url(#dot)"
marker-end="url(#dot)" />
</svg>
{{EmbedLiveSample('Drawing_polymarkers', 200, 200)}}
Using context fill and stroke
The following example shows how to use the context-fill
and context-stroke
values to make a marker use the same fill and stroke as the shape it is attached to.
<svg viewBox="0 0 50 50" xmlns="http://www.w3.org/2000/svg">
<marker
id="circle"
markerWidth="6"
markerHeight="6"
refX="3"
refY="3"
markerUnits="strokeWidth">
<circle cx="3" cy="3" r="2" stroke="context-stroke" fill="context-fill" />
</marker>
<style>
path {
marker: url(#circle);
}
</style>
<path d="M 10,10 30,10 h 10" stroke="black" />
<path d="M 10,20 30,20 h 10" stroke="blue" fill="red" />
<path d="M 10,30 30,30 h 10" stroke="red" fill="none" />
<path d="M 10,40 30,40 h 10" stroke="gray" fill="blue" stroke-width="1.5" />
</svg>
html,
body,
svg {
height: 100%;
}
{{EmbedLiveSample('Using_context_fill_and_stroke', 200, 200)}}
Attributes
{{SVGAttr("markerHeight")}}
- : This attribute defines the height of the marker viewport.
Value type: <length> ; Default value:
3
; Animatable: yes
- : This attribute defines the height of the marker viewport.
Value type: <length> ; Default value:
{{SVGAttr("markerUnits")}}
- : This attribute defines the coordinate system for the attributes
markerWidth
,markerHeight
and the contents of the<marker>
. Value type:userSpaceOnUse
|strokeWidth
; Default value:strokeWidth
; Animatable: yes
- : This attribute defines the coordinate system for the attributes
{{SVGAttr("markerWidth")}}
- : This attribute defines the width of the marker viewport.
Value type: <length> ; Default value:
3
; Animatable: yes
- : This attribute defines the width of the marker viewport.
Value type: <length> ; Default value:
{{SVGAttr("orient")}}
- : This attribute defines the orientation of the marker relative to the shape it is attached to.
Value type:
auto
|auto-start-reverse
|<angle> ; Default value:0
; Animatable: yes
- : This attribute defines the orientation of the marker relative to the shape it is attached to.
Value type:
{{SVGAttr("preserveAspectRatio")}}
- : This attribute defines how the svg fragment must be deformed if it is embedded in a container with a different
{{glossary("aspect ratio")}}
. Value type: (none
|xMinYMin
|xMidYMin
|xMaxYMin
|xMinYMid
|xMidYMid
|xMaxYMid
|xMinYMax
|xMidYMax
|xMaxYMax
) (meet
|slice
)? ; Default value:xMidYMid meet
; Animatable: yes
- : This attribute defines how the svg fragment must be deformed if it is embedded in a container with a different
{{SVGAttr("refX")}}
- : This attribute defines the x coordinate for the reference point of the marker.
Value type:
left
|center
|right
|<coordinate> ; Default value:0
; Animatable: yes
- : This attribute defines the x coordinate for the reference point of the marker.
Value type:
{{SVGAttr("refY")}}
- : This attribute defines the y coordinate for the reference point of the marker.
Value type:
top
|center
|bottom
|<coordinate> ; Default value:0
; Animatable: yes
- : This attribute defines the y coordinate for the reference point of the marker.
Value type:
{{SVGAttr("viewBox")}}
- : This attribute defines the bound of the SVG viewport for the current SVG fragment. Value type: <list-of-numbers> ; Default value: none; Animatable: yes
Usage context
{{svginfo}}
Specifications
{{Specifications}}
Browser compatibility
{{Compat}}
See also
- Related marker properties:
{{SVGAttr("marker-start")}}
,{{SVGAttr("marker-mid")}}
, and{{SVGAttr("marker-end")}}