refX - SVG: Scalable Vector Graphics 编辑

The refX attribute defines the x coordinate of an element’s reference point.

Two elements are using this attribute: <marker> and <symbol>

marker

For <marker>, refX defines the x coordinate of the marker’s reference point, which is to be placed exactly at the marker’s position on the shape.

<length-percentage>

Lengths are interpreted as being in the coordinate system of the marker contents, after application of the viewBox and preserveAspectRatio attributes.

Percentage values are interpreted as being a percentage of the viewBox width.

<number>

Numbers are interpreted as being in the coordinate system of the marker contents, after application of the viewBox and preserveAspectRatio attributes.

left

The reference point of the marker is placed at the left edge of the shape.

center

The reference point of the marker is placed at the horizontal center of the shape.

right

The reference point of the marker is placed at the right edge of the shape.

symbol

For <symbol>, refX defines the x coordinate of the symbol, which is defined by the cumulative effect of the x attribute and any transformations on the <symbol> and its host <use> element.

Unlike other positioning attributes, refX is interpreted as being in the coordinate system of the symbol contents, after application of the viewBox and preserveAspectRatio attributes. If the attribute is not specified, no horizontal adjustment is made, and the left side of the symbol’s rectangular viewport region (regardless of the viewBox coordinate) is positioned at the x coordinate.

For backwards compatibility, the behavior when refX is not specified on a <symbol> element is different from when it is specified with a value of 0, and therefore different from the behavior when an equivalent attribute is not specified on a <marker> element.

<length-percentage>

Lengths are interpreted as being in the coordinate system of the marker contents, after application of the viewBox and preserveAspectRatio attributes.

Percentage values are interpreted as being a percentage of the viewBox width.

<number>

Numbers are interpreted as being in the coordinate system of the marker contents, after application of the viewBox and preserveAspectRatio attributes.

left

The reference point of the marker is placed at the left edge of the shape.

center

The reference point of the marker is placed at the horizontal center of the shape.

right

The reference point of the marker is placed at the right edge of the shape.

Specifications

See also

• refY