path element | SVGPathElement object

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path element | SVGPathElement object
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[This documentation is preliminary and is subject to change.]

Defines a path using commands (moveto, line, cubic curves, quadratic Bézier curves, arc, and closepath) and coordinates.


Syntax

<SVGPathElement>
Standards information

Scalable Vector Graphics: Paths, Section 8.5.23
Members

The SVGPathElement object has the following types of members:

Events
Methods
Properties
Events

The SVGPathElement object has the following events.

Event Description
onload
Occurs when the browser has fully parsed the element and all of its descendants.


Methods

The SVGPathElement object has the following methods.

Method Description
createSVGPathSegArcAbs
Returns a stand-alone, parentless SVGPathSegArcAbs object.
createSVGPathSegArcRel
Returns a stand-alone, parentless SVGPathSegArcRel object.
createSVGPathSegClosePath
Returns a stand-alone, parentless SVGPathSegClosePath object.
createSVGPathSegCurvetoCubicAbs
Returns a stand-alone, parentless SVGPathSegCurvetoCubicAbs object.
createSVGPathSegCurvetoCubicRel
Returns a stand-alone, parentless SVGPathSegCurvetoCubicRel object.
createSVGPathSegCurvetoCubicSmoothAbs
Returns a stand-alone, parentless SVGPathSegCurvetoCubicSmoothAbs object.
createSVGPathSegCurvetoCubicSmoothRel
Returns a stand-alone, parentless SVGPathSegCurvetoCubicSmoothRel object.
createSVGPathSegCurvetoQuadraticAbs
Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticAbs object.
createSVGPathSegCurvetoQuadraticRel
Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticRel object.
createSVGPathSegCurvetoQuadraticSmoothAbs
Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothAbs object.
createSVGPathSegCurvetoQuadraticSmoothRel
Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothRel object.
createSVGPathSegLinetoAbs
Returns a stand-alone, parentless SVGPathSegLinetoAbs object.
createSVGPathSegLinetoHorizontalAbs
Returns a stand-alone, parentless SVGPathSegLinetoHorizontalAbs object.
createSVGPathSegLinetoHorizontalRel
Returns a stand-alone, parentless SVGPathSegLinetoHorizontalRel object.
createSVGPathSegLinetoRel
Returns a stand-alone, parentless SVGPathSegLinetoRel object.
createSVGPathSegLinetoVerticalAbs
Returns a stand-alone, parentless SVGPathSegLinetoVerticalAbs object.
createSVGPathSegLinetoVerticalRel
Returns a stand-alone, parentless SVGPathSegLinetoVerticalRel object.
createSVGPathSegMovetoAbs
Returns a standalone parentless SVGPathSegMovetoAbs object.
createSVGPathSegMovetoRel
Returns a stand-alone, parentless SVGPathSegMovetoRel object.
getBBox
Gets the bounding box, in current user space, of the geometry of all contained graphics elements.
getCTM
Gets the transformation matrix that transforms from the current user units to the viewport coordinate system for the nearestViewportElement object.
getPathSegAtLength
Gets the index of pathSegList by using the specified distance along the path.
getPointAtLength
Gets the (x,y) coordinate in user space that is the specified distance along the path.
getScreenCTM
Gets the transformation matrix from the current user units to the screen coordinate system.
getTotalLength
Gets the total length of the path, as a distance in the current user coordinate system.
getTransformToElement
Gets the transformation matrix that transforms from the user coordinate system on the current element to the user coordinate system on the specified target element.
hasExtension
Determines if the specified extension is supported.


Properties

The SVGPathElement object has the following properties.

Property Description
animatedNormalizedPathSegList
Gets or sets the normalized animated contents of the d attribute.
animatedPathSegList
Gets or sets the animated contents of the d attribute in a form that matches the SVG syntax.
className
Gets the names of the classes that are assigned to this object.
clipPath
Sets or retrieves a reference to the SVG graphical object that will be used as the clipping path.
farthestViewportElement
Gets a value that represents the farthest ancestor svg element.
fill
Sets or retrieves a value that indicates the color to paint the interior of the given graphical element.
fillOpacity
Sets or retrieves a value that specifies the opacity of the painting operation that is used to paint the interior of the current object.
fillRule
Sets or retrieves a value that indicates the algorithm that is to be used to determine what parts of the canvas are included inside the shape.
focusable
Determines if an element can acquire keyboard focus (that is, receive keyboard events) and be a target for field-to-field navigation actions (such as when a user presses the Tab key).
marker
Sets or retrieves a value that specifies the marker symbol that is used for all vertices on the given path element or basic shape.
markerEnd
Sets or retrieves a value that defines the arrowhead or polymarker that is drawn at the final vertex of a given path element or basic shape.
markerMid
Sets or retrieves a value that defines the arrowhead or polymarker that is drawn at every other vertex (that is, every vertex except the first and last) of a given path element or basic shape.
markerStart
Sets or retrieves a value that defines the arrowhead or polymarker that is drawn at the first vertex of a given path element or basic shape.
mask
Sets or retrieves a value that indicates a SVG mask.
nearestViewportElement
Gets a value that indicates which element established the current viewport.
normalizedPathSegList
Gets or sets the normalized static contents of the d attribute.
ownerSVGElement
Gets the nearest ancestor svg element.
pathLength
pathSegList
Gets or sets the static contents of the d attribute in a form that matches the SVG syntax.
pointerEvents
Sets or retrieves a value that specifies under what circumstances a given graphics element can be the target element for a pointer event in SVG.
requiredExtensions
Gets a white space-delimited list of required language extensions.
requiredFeatures
Gets or sets a white space-delimited list of feature strings.
stroke
Sets or retrieves a value that indicates the color to paint along the outline of a given graphical element.
strokeDasharray
Sets or retrieves one or more values that indicate the pattern of dashes and gaps used to stroke paths.
strokeDashoffset
Sets or retrieves a value that specifies the distance into the dash pattern to start the dash.
strokeLinecap
Sets or retrieves a value that specifies the shape to be used at the end of open subpaths when they are stroked.
strokeLinejoin
Sets or retrieves a value that specifies the shape to be used at the corners of paths or basic shapes when they are stroked.
strokeMiterlimit
Sets or retrieves a value that indicates the limit on the ratio of the length of miter joins (as specified in the strokeLinejoin property).
strokeOpacity
Sets or retrieves a value that specifies the opacity of the painting operation that is used to stroke the current object.
strokeWidth
Sets or retrieves a value that specifies the width of the stroke on the current object.
style
Gets a style object.
systemLanguage
Gets or sets a comma-separated list of language names.
transform
Gets the value of a transform attribute.
viewportElement
Gets the element that established the current viewport.
xmlbase
Gets or sets the base attribute on the element.
xmllang
Gets or sets a value that specifies the language that is used in the contents and attribute values of an element.
xmlspace
Gets or sets a value that indicates whether white space is preserved in character data.


Remarks

Note  In addition to the attributes, properties, events, methods, and styles listed above, SVG elements also inherent core HTML attributes, properties, events, methods, and styles.

Path data can contain newline characters and thus can be broken up into multiple lines to improve readability. Because of line-length limitations with certain related tools, it is recommended to split long path data strings across multiple lines, with each line not exceeding 255 characters. Also note that newline characters are allowed only at certain places within path data.

The syntax of path data is concise in order to allow for minimal file size and efficient downloads, because many SVG files will be dominated by their path data. Some of the ways that SVG attempts to minimize the size of path data are as follows:

All instructions are expressed as one character (for example, a moveto is expressed as an M).
Superfluous white space and separators such as commas can be eliminated (for example, "M 100 100 L 200 200" contains unnecessary spaces and could be expressed more compactly as "M100 100L200 200").
The command letter can be eliminated on subsequent commands if the same command is used multiple times in a row (for example, you can drop the second L in "M 100 200 L 200 100 L -100 -200" and use "M 100 200 L 200 100 -100 -200" instead).
Relative versions of all commands are available (uppercase means absolute coordinates, lowercase means relative coordinates).
Alternate forms of lineto are available to optimize the special cases of horizontal and vertical lines (absolute and relative).
Alternate forms of curve are available to optimize the special cases where some of the control points on the current segment can be determined automatically from the control points on the previous segment.
The path-data syntax is a prefix notation (that is, commands followed by parameters). The only allowable decimal point is a Unicode U+0046 FULL STOP (".") character (also referred to in Unicode as PERIOD, dot, and decimal point) and no other delimiter characters are allowed. (For example, the following is an invalid numeric value in a path data stream: "13,000.56". Instead, say: "13000.56".)

For the relative versions of the commands, all coordinate values are relative to the current point at the start of the command. For example, the absolute version of moveto is M whereas its relative form is indicated with a lowercase m. Absolute versus relative path commands are discussed in the following table.

Note  In the Path Command Table below, the following notation is used.

   () Indicates grouping of parameters.
   + One or more of the given parameter(s) is required.




Path Command Table
Command Name Parameters Description
M (absolute)
m (relative)
moveto (x y)+
Starts a new path or subpath at the given (x,y) coordinates. M indicates that absolute coordinates will follow; m indicates that relative coordinates will follow. If a moveto is followed by multiple pairs of coordinates, the subsequent pairs are treated as implicit lineto commands. Hence, implicit lineto commands will be relative if the moveto is relative, and absolute if the moveto is absolute. If a relative movetom appears as the first element of the path, then it is treated as a pair of absolute coordinates. In this case, subsequent pairs of coordinates are treated as relative even though the initial moveto is interpreted as an absolute moveto.
The moveto commands (M or m) establish a new current point. The effect is as if the "pen" were lifted and moved to a new location. A path data segment (if there is one) must begin with a moveto command. Subsequent moveto commands (that is, when the moveto is not the first command) represent the start of a new subpath.
Z or z closepath (none)
Closes the current subpath by drawing a straight line from the current point to current subpath's initial point. Because the Z and z commands take no parameters, they have an identical effect.
The closepath (Z or z) ends the current subpath and causes an automatic straight line to be drawn from the current point to the initial point of the current subpath. If a closepath is followed immediately by a moveto, then the moveto identifies the start point of the next subpath. If a closepath is followed immediately by any other command, then the next subpath starts at the same initial point as the current subpath.
When a subpath ends in a closepath, it differs in behavior from what happens when "manually" closing a subpath via a lineto command in how 'stroke-linejoin' and 'stroke-linecap' are implemented. With closepath, the end of the final segment of the subpath is "joined" with the start of the initial segment of the subpath using the current value of 'stroke-linejoin'. If you instead "manually" close the subpath via a lineto command, the start of the first segment and the end of the last segment are not joined but instead are each capped using the current value of 'stroke-linecap'. At the end of the command, the new current point is set to the initial point of the current subpath.
L (absolute)
l (relative)
lineto (x y)+ Draws a line from the current point to the given (x,y) coordinates, which becomes the new current point. L indicates that absolute coordinates will follow; l indicates that relative coordinates will follow. A number of coordinates pairs may be specified to draw a polyline. At the end of the command, the new current point is set to the final set of coordinates provided.
H (absolute)
h (relative)
horizontal lineto x+ Draws a horizontal line from the current point (cpx, cpy) to (x, cpy). H indicates that absolute coordinates will follow; h indicates that relative coordinates will follow. Multiple x values can be provided (although usually this doesn't make sense). At the end of the command, the new current point becomes (x, cpy) for the final value of x.
V (absolute)
v (relative)
vertical lineto y+ Draws a vertical line from the current point (cpx, cpy) to (cpx, y). V indicates that absolute coordinates will follow; v indicates that relative coordinates will follow. Multiple y values can be provided (although usually this doesn't make sense). At the end of the command, the new current point becomes (cpx, y) for the final value of y.
C (absolute)
c (relative)
curveto (x1 y1 x2 y2 x y)+
A cubic Bézier segment is defined by a start point, an end point, and two control points.
Draws a cubic Bézier curve from the current point to (x,y) using (x1,y1) as the control point at the beginning of the curve and (x2,y2) as the control point at the end of the curve. C indicates that absolute coordinates will follow; c indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
S (absolute)
s (relative)
Shorthand: smooth curveto (x2 y2 x y)+ Draws a cubic Bézier curve from the current point to (x,y). The first control point is assumed to be the reflection of the second control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not a C, c, S or s, assume the first control point is coincident with the current point.) (x2,y2) is the second control point (that is, the control point at the end of the curve). S indicates that absolute coordinates will follow; s indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
Q (absolute)
q (relative)
quadratic Bézier curveto (x1 y1 x y)+
A quadratic Bézier segment is defined by a start point, an end point, and one control point.
Draws a quadratic Bézier curve from the current point to (x,y) using (x1,y1) as the control point. Q indicates that absolute coordinates will follow; q indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
T (absolute)
t (relative)
Shorthand: smooth quadratic Bézier curveto (x y)+ Draws a quadratic Bézier curve from the current point to (x,y). The control point is assumed to be the reflection of the control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not a Q, q, T or t, assume the control point is coincident with the current point.) T indicates that absolute coordinates will follow; t indicates that relative coordinates will follow. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
A (absolute)
a (relative)
elliptical arc (rx ry x-axis-rotation large-arc-flag sweep-flag x y)+
An elliptical arc segment draws a segment of an ellipse.
Draws an elliptical arc from the current point to (x, y). The size and orientation of the ellipse are defined by two radii (rx, ry) and an x-axis rotation, which indicates how the ellipse as a whole is rotated relative to the current coordinate system. The center (cx, cy) of the ellipse is calculated automatically to satisfy the constraints imposed by the other parameters. large-arc-flag and sweep-flag contribute to the automatic calculations and help determine how the arc is drawn. For more information, see the following discussion.


With respect to the last row of the above table, the elliptical arc command draws a section of an ellipse that meets the following constraints:

The arc starts at the current point.
The arc ends at point (x, y).
The ellipse has the two radii (rx, ry).
The x-axis of the ellipse is rotated by x-axis rotation relative to the x-axis of the current coordinate system.
For most situations, there are actually four different arcs (two different ellipses, each with two different arc sweeps) that satisfy these constraints. large-arc-flag and sweep-flag indicate which one of the four arcs is drawn, as follows:

Of the four candidate arc sweeps, two will represent an arc sweep of greater than or equal to 180 degrees (the "large-arc"), and two will represent an arc sweep of less than or equal to 180 degrees (the "small-arc"). If large-arc-flag is '1', then one of the two larger arc sweeps will be chosen; otherwise, if large-arc-flag is '0', one of the smaller arc sweeps will be chosen.
If sweep-flag is '1', then the arc will be drawn in a "positive-angle" direction (that is, the ellipse formula x=cx+rx*cos(?) and y=cy+ry*sin(?) is evaluated such that theta starts at an angle corresponding to the current point and increases positively until the arc reaches (x,y)). A value of 0 causes the arc to be drawn in a "negative-angle" direction (that is, theta starts at an angle value corresponding to the current point and decreases until the arc reaches (x,y)).
The following image illustrates the four combinations of large-arc-flag and sweep-flag and the four different arcs that will be drawn based on the values of these flags. For each case, the following path data command was used:

<path d="M 125,75 a100,50 0 ?,? 100,50" style="fill:none; stroke:red; stroke-width:6"/>

where "?,?" is replaced by "0,0" "0,1" "1,0" and "1,1" to generate the four possible cases.



Examples

In the following code example, the path element is used to create a hotpink curved path. Copy this sample to a text file and save it with the .html file extension. Run it in a Metro style app using JavaScript to see the path.

It should look like this:




<!DOCTYPE HTML>
<html>

  <head>
  </head>

  <body>
    <svg width="400" height="400">
  <path d="M 50,100 Q 150,50 250,100" stroke="hotpink" stroke-width="10" fill="white"/>
    </svg>
  </body>
</html>


Requirements

Minimum supported client

Windows Vista with SP1, Windows 7
Minimum supported server

Windows Server 2008 R2
Header

Mshtml.h
IDL

Mshtml.idl
DLL

Mshtml.dll




Build date: 9/7/2011