Linking — SVG 2

Linking — SVG 2
Chapter 16: Linking
16.1. References
16.1.1. Overview
On the Internet, resources are identified using
URLs
(Internationalized Resource Identifiers). For
example, an SVG file called someDrawing.svg located at
URL
An
URL
can also address a particular element within an XML
document by including an
URL
fragment
identifier as part of the
URL
. An
URL
which includes an
URL
fragment identifier consists of an optional base
URL
, followed by a "#" character,
followed by the
URL
fragment identifier. For example, the
following
URL
can be used to specify the element whose ID is
"Lamppost" within file someDrawing.svg:
16.1.2. Definitions
URL reference
An URL reference is an Internationalized Resource Identifier, as defined in
Internationalized Resource Identifiers
rfc3987
]. See
References
and
References and the
‘defs’
element
URL reference with fragment identifier
An Internationalized Resource Identifier [
rfc3987
] that
can include an or
and a identifier of the fragment in that resource. See
References and the
‘defs’
element
. URL reference with fragment identifiers are commonly used to reference
paint servers
external file reference
URL reference
or
URL reference with fragment identifier
which refers to a resource that is not part of the current document.
same-document URL reference
URL reference with fragment identifier
where the non-fragment part of the URL refers to the current document.
data URL
URL reference
to an embedded document
specified using the
"data" URL scheme
rfc2397
].
Data URL references are neither
external file references
nor
same-document URL references
circular reference
URL references
that directly or indirectly reference
themselves are treated as invalid circular references.
What constitutes a circular reference will depend on how the referenced resource is used,
and may include a reference to an ancestor of the current element.
unresolved reference
A reference that is still being processed,
and has not yet resulted in either an error or an identified resource.
invalid reference
Any of the following are invalid references:
A circular reference.
URL reference
that results in an error
during
processing
URL reference
that cannot be resolved.
URL references
to elements which are
inappropriate targets for the given reference shall be treated as invalid
references
(see
Valid URL targets
for appropriate targets).
For example, the
clip-path
property can only refer to
clipPath
elements. The property setting
clip-path:url(#MyElement)
is an
invalid reference if the referenced element is not a
clipPath
Invalid references may or may not be an error
(see
Error processing
),
depending on whether the referencing property or attribute defines fallback behavior.
16.1.3. URLs and URIs
Internationalized Resource Identifiers (
URLs
) are a more generalized
complement to Uniform Resource Identifiers (URIs). An
URL
is a sequence
of characters from the Universal Character Set [
UNICODE
].
A URI is constructed from a much more restricted set of characters. All URIs are
already conformant
URLs
. A mapping from
URLs
to URIs is defined by
the
URL
specification, which means that URLs can be used instead of URIs
in XML documents, to identify resources.
URLs
can be converted to URIs
for resolution on a network, if the protocol does not support
URLs
directly.
Previous versions of SVG, following XLink, defined an URL reference type
as a URI
or as a sequence of characters which must result in an URL after a
particular escaping procedure was applied
. The escaping procedure was repeated in the
XLink 1.0 specification [
xlink
], and in the
W3C XML Schema Part 2: Datatypes specification [
xmlschema-2
].
This copying introduced the possibility of error and divergence, but was done
because the
URL
specification was not yet standardized.
In this specification, the correct term
URL
is used for this "URI or sequence of characters
plus an algorithm" and the escaping method, which turns URLs into URIs, is defined by reference to the
URL specification
rfc3987
],
which has since become an IETF Proposed Standard. Other W3C specifications are
expected to be revised over time to remove these duplicate descriptions of the
escaping procedure and to refer to
URL
directly.
16.1.4. Syntactic forms: URL and
In SVG, most structural relationships between two elements
are specified using a
URL
value in an
‘href’
attribute.
To describe linking relationships,
this specification uses two different data types in attribute and property values:
URL
and

The linking guidelines in this chapter apply to URLs specified with either syntax.
The
URL
data type is a simple URL string.
In SVG, most structural relationships between two elements
are specified using a
URL
value in an
‘href’
attribute.

is different from
URL
and represents a CSS
url()
function value.
(See CSS Values and Units for further details [
css-values
]).

may be used for
presentation attributes
and their corresponding CSS properties
css-values
].
URL
is not a valid value for
presentation attributes
for structural
relationships purposes. No non-
presentation attribute
allows

as value.
SVG makes extensive use of
URL
references, both absolute and relative,
to other objects.
For example, a
linearGradient
element
may be based on another gradient element,
so that only the differences between the two need to be specified,
by referencing the source gradient with a URL in the
href
attribute:
...
href="#SourceGradient">...
To fill a rectangle with that gradient,
the value of the rectangle's
fill
property may be set so as to
include a URL reference to the relevant
linearGradient
element;
here is an example:

16.1.5. URL reference attributes
URL references
are normally specified with an
‘href’
attribute.
The value of this attribute forms a reference for the desired resource (or
secondary resource, if there is a fragment identifier).
The value of the
‘href’
attribute must be a URL.
Because it is impractical for any application to check that
a value is an
URL reference
, this specification follows the lead
of the
URL Specification
in this matter and imposes no such conformance testing
requirement on
SVG authoring tools
An invalid URL does not make an SVG document non-conforming.
SVG user agents are only required to process URLs when needed,
as specified in
Processing of URL references
16.1.6. Deprecated XLink URL reference attributes
In previous versions of SVG, the
‘href’
attribute was specified in the XLink namespace [
xlink
] namespace.
This usage is now deprecated and instead
URL references
should be
specified using the
‘href’
attribute without
a namespace.
For backwards compatibility, the deprecated
xlink:href
attribute
is defined below along with the
xlink:title
attribute which has also
been deprecated.
Attribute definitions:
Name
Value
Initial value
Animatable
xlink:href
URL
[URL]
(none)
(see below)
For backwards compatibility, elements with an
‘href’
attribute also recognize an
‘href’
attribute in the XLink namespace [
xlink
].
When the
‘href’
attribute is present in
both
the XLink namespace and without a namespace, the
value of the attribute without a namespace shall be used. The attribute in
the XLink namespace shall be ignored.
conforming SVG generator
must generate
‘href’
attributes without a namespace.
However, it may
also
generate
‘href’
attributes in the XLink namespace to provide backwards compatibility.
This attribute is
Animatable
if and only if the corresponding
‘href’
attribute is defined to be
animatable.
Name
Value
Initial value
Animatable
xlink:title

(none)
no
Deprecated attribute to describe the meaning of
a link or resource in a human-readable fashion.
New content should use a
‘title’
child element rather than a
‘xlink:title’
attribute.
The use of this information is highly dependent on the type of processing
being done. It may be used, for example, to make titles
available to applications used by visually impaired users,
or to create a table of links, or to present help text that
appears when a user lets a mouse pointer hover over a
starting resource.
The
‘title’
attribute, if used, must be
in the XLink namespace.
Refer to the
XML Linking Language
(XLink)
xlink
].
When using the deprecated XLink attributes
xlink:href
or
xlink:title
an explicit XLink namespace declaration must be provided
xml-names
],

One simple way to provide such an XLink namespace declaration
is to include an
‘xmlns’
attribute
for the XLink namespace on the
svg
element for content that uses
XLink attributes. For example:



16.1.7. Processing of URL references
URLs are processed to identify a resource at the time they are needed, as follows:
For the
href
attribute of the
element,
at the time the link is activated by the user.
For all other
‘href’
attributes,
at the time the element is
connected
to a document,
or at the time when the attribute is set, whichever is later.
For source URLs on embedded HTML media elements,
as required based on source selection rules
in the HTML specification
HTML
].
For all presentation attributes and style properties,
at the time the property is required for rendering an element.
Legacy
xlink:href
attributes are processed
at the time a corresponding
‘href’
attribute would be processed,
but only if no such
‘href’
attribute exists on the element.
Processing a URL involves three steps:
generating the absolute URL;
fetching the document (if required);
identifying the target element (if required).
A URL reference is
unresolved
until processing either results in an
invalid reference
or in the identification of the target resource.
Unresolved references in the non-presentation attributes of
structurally external elements
prevent the
load event
from firing. User agents may place time limits on the resolution of references
that are not
same-document URL references
after which the reference is treated as a network error
(and therefore as an
invalid reference
).
For
same-document URL references
in a dynamic document,
modifications or animations of attributes or properties,
or removal of elements from the DOM,
may cause an URL reference to return to the
unresolved
state.
The user agent must once again attempt to resolve the URI to identify the referenced resource.
16.1.7.1. Generating the absolute URL
If the
URL reference
is relative, its absolute version must be computed before use.
The absolute URL should be generated using one of the following methods:
as described in
CSS Values and Units
if the reference occurs in a CSS file or in a
presentation attribute
css-values
as described in
XML Base
before use [
xmlbase
if the reference occurs in any other attribute in an XML document
as described in the
HTML specification
if the reference occurs in a non-presentation attribute
in an HTML document that is not an XML document [
HTML
The
‘xml:base’
attribute
will only have an effect in XML documents;
this includes SVG documents and XHTML documents but not HTML documents that are not XML.
In contrast, a
base
element
affects relative URLs in any SVG or HTML document,
by altering the
document base URL
If the protocol, such as HTTP, does not support
URLs
directly,
the
URL
must be converted to a URI by the user agent, as described
in section 3.1 of the
URL specification
rfc3987
].
After generating the absolute URL:
If the URL is being processed following the activation of a link,
the user agent must follow the
algorithm for navigating to a URL
described in the HTML specification [
HTML
].
The outcome of this algorithm varies depending on the
target
browsing context and security restrictions between browsing contexts,
and on whether the link is to the same document as is currently contained in that browsing context
(in which case the fragment is navigated without reloading the document).
If the document that was navigated was an SVG document,
then adjust the target behavior as described in
Linking into SVG content
If the URL being processed is only
valid
if it refers to a complete document file
(such as the
‘href’
attribute of
an
image
and
script
element),
continue as indicated in
Fetching the document
(regardless of whether the URL is to the same document or not).
In all other cases, the URL is for a resource to be used in this SVG document.
The user agent must parse the URL to separate out the target fragment from the rest of the URL,
and compare it with the document base URL.
If all parts other than the target fragment are equal,
this is a
same-document URL reference
and processing the URL must continue
as indicated in
Identifying the target element
with the current document as the referenced document.
Otherwise, the URL references a separate document,
and the user agent must continue processing the URL
as indicated in
Fetching the document
As defined in
CSS Values and Units
a fragment-only URL in a style property must be treated as
same-document URL reference
regardless of the file in which the property was declared.
16.1.7.2. Fetching the document
SVG properties and attributes may reference other documents.
When processing such a URL,
the user agent should fetch the referenced document
as described in this section,
except under the following conditions:
If the URL reference is from
the
href
attribute on
SVG animation elements
only
same-document URL
references are allowed
svg-animation
].
A URL referring to a different document is invalid
and the document must not be fetched.
If the document containing the reference is being processed in
secure static mode
or
secure animated mode
external file references
are disallowed.
Unless the reference is a
data URL
the user agent must treat the reference as if there was a network error,
making this an
invalid reference
If any other security restrictions
on the browsing context or user agent prevent accessing the external file,
then the user agent must treat the reference as if there was a network error.
When fetching external resources from the Internet,
user agents must use a
potentially CORS-enabled request
as defined in HTML [
HTML
with the
corsAttributeState
as follows:
For an
‘href’
reference on an
image
element or
script
element,
the CORS state specified by the
crossorigin
attribute.
For a reference from a style property or presentation attribute,
the "anonymous" state.
For all other references,
the "no-cors" state.
base
The request's
origin
is computed using the
same rules as HTML
with an SVG
script
element treated like an HTML
script
element,
and an SVG
image
element treated like an HTML
img
element.
The
default origin behaviour
must be set to
taint
A future SVG specification may enable CORS references
on other SVG elements with
‘href’
attributes.
If the fetching algorithm results in an error or an empty response body,
the reference URL is treated as an
invalid reference
If a valid response is returned,
and the
valid URL targets
for the reference
include specific element types,
the user agent must continue by
Processing the subresource document
Otherwise (if only entire-document the URL references are valid),
then the fetched document is the referenced resource.
16.1.7.3. Processing the subresource document
Otherwise, the subresource must be parsed to identify the target element.
If the fetched document is a type that the user agent can parse
to create a document object model,
it must process it in
secure static mode
(meaning, do not fetch any additional external resources
and do not run scripts or play animations).
The document model generated for an external subresource reference
must be immutable (read-only) and cannot be modified.
If a document object model can be generated from the fetched file,
processing the URL must continue
as indicated in
Identifying the target element
with the parsed subresource document as the referenced document.
The user agent may commence the target-identification process
prior to completely parsing the document.
User agents may maintain a list of external resource URLs
and their associated parsed documents,
and may re-use the documents for subsequent references,
so long as doing so does not violate the processing mode,
caching, and CORS requirements on the resource.
16.1.7.4. Identifying the target element
For URL references to a specific element,
whether the reference is valid depends on whether
the element can be located within the referenced document
and whether it is of an allowed type.
Using the referenced document identified in previous processing steps
(either an external subresource document or the current document),
the target element is identified as follows:
If the URL does not specify a specific element in a target fragment,
the target element is the root element of the referenced document.
Otherwise, the URL targets a specific element.
If a matching element currently exists in the referenced document,
then it is the target element.
Otherwise, there is no currently matching element.
If the referenced document is immutable,
then the URL reference is
invalid
An external subresource document is always immutable once fully parsed;
the current document is also immutable once parsed
if it is being processed in any mode other than
dynamic interactive mode
Otherwise, observe mutations to the referenced document
until the URL can be successfully resolved
to define a target element,
or until the document becomes immutable
(e.g., a non-dynamic document finishes parsing).
The target element provides the referenced resource
if (and only if) it is a
valid URL target
for the reference.
16.1.7.5. Valid URL targets
The valid target element types for
‘href’
(or
xlink:href
) attributes are based on the element that has the attribute, as follows:
the
element can reference any local or non-local resource
the
image
element must reference a document that can be processed as an image
the
linearGradient
element must reference a different
linearGradient
or
radialGradient
element
the
pattern
element must reference another
pattern
element
the
radialGradient
element must reference a
linearGradient
or another
radialGradient
element
the
script
element must reference an external document that provides the script content
the
textPath
element must reference an element type
that implements the
SVGGeometryElement
interface
the
use
element must reference an SVG-namespaced element
The valid target element types for style properties defined in this specification are as follows:
the
fill
property (see
Specifying paint
for reference rules)
the
marker
marker-start
marker-mid
and
marker-end
properties must reference a
marker
element.
the
shape-inside
and
shape-subtract
properties must reference an element type
that implements the
SVGGeometryElement
interface,
or a document that can be processed as an image
the
stroke
property (see
Specifying paint
for reference rules)
For references that allow either a reference to a target element, or to an image file
(such as the
shape-inside
shape-subtract
, and
mask
properties),
the user agent must identify the target element and determine whether it is a valid target.
If the resolved target element is not an allowed element type,
the referenced resource is the entire document file;
the target fragment is used in processing that file as with any other image.
In all other cases, if the resolved target element type (or document type) is not allowed for the URL reference,
it is an
invalid reference
16.2. Links out of SVG content: the
‘a’
element
SVG provides an
element, to indicate links (also known
as
hyperlinks
or
Web links
).
An
element forms a link if it has a
href
or
xlink:href
attribute; without these attributes the
element is an inactive placeholder for a link.
SVG 1.1 defined links in terms of the XLink specification ([
XLink
]),
using attributes defined in the XLink namespace.
SVG 2 uses an alternative set of attributes in the default namespace that are consistent with HTML links, and
deprecates the XLink attributes
The
element may
contain any element that its parent may contain, except for another
element;
the same element is used for both graphical and textual linked content.
Links may not be nested;
if an
element is a descendent of another hyperlink element
(whether in the SVG namespace or another namespace),
user agents must ignore its href attribute and treat it as inactive.
The invalid
element must still be rendered as a generic container element.
The rendering of invalid nested links is at risk, and will likely be synchronized with any decisions regarding the rendering of unknown elements.
For pointer events processing,
a linked hit region is defined for each separate rendered element contained
within the
element (according to the value of their
pointer-events
property),
rather than for the bounding box of the
element itself.
User agents must also ensure that all links are
focusable
and can be activated by keyboard commands.
The remote resource (the destination for the link) is defined by
URL
specified by the
href
attribute on the
element. The remote resource may be any Web resource (e.g., an image, a video
clip, a sound bite, a program, another SVG document, an HTML document, an
element within the current document, an element within a different document, etc.).
In response to user activation of a link
(by clicking with the mouse, through keyboard input, voice commands, etc.),
user agents should attempt to fetch the specified resource document and either display it or make it available as a downloaded file.
Example link01
assigns
a link to an ellipse.


Example link01 - a link on an ellipse

fill="none" stroke="blue" stroke-width=".03"/>

fill="red" />


Example link01
View this example as SVG (SVG-enabled browsers only)
If the above SVG file is viewed by a user agent that supports both
SVG and HTML, then clicking on the ellipse will cause the current window
or frame to be replaced by the W3C home page.
Categories:
Container element
renderable element
Content model:
Descriptive content, plus any element or text allowed by its parent's content model, except for another a element. If the parent is a switch element, use the content model of the nearest ancestor that isn't a switch.
Attributes:
aria attributes
aria-activedescendant
aria-atomic
aria-autocomplete
aria-busy
aria-checked
aria-colcount
aria-colindex
aria-colspan
aria-controls
aria-current
aria-describedby
aria-details
aria-disabled
aria-dropeffect
aria-errormessage
aria-expanded
aria-flowto
aria-grabbed
aria-haspopup
aria-hidden
aria-invalid
aria-keyshortcuts
aria-label
aria-labelledby
aria-level
aria-live
aria-modal
aria-multiline
aria-multiselectable
aria-orientation
aria-owns
aria-placeholder
aria-posinset
aria-pressed
aria-readonly
aria-relevant
aria-required
aria-roledescription
aria-rowcount
aria-rowindex
aria-rowspan
aria-selected
aria-setsize
aria-sort
aria-valuemax
aria-valuemin
aria-valuenow
aria-valuetext
role
conditional processing attributes
requiredExtensions
systemLanguage
core attributes
id
tabindex
autofocus
lang
xml:space
class
style
global event attributes
oncancel
oncanplay
oncanplaythrough
onchange
onclick
onclose
oncopy
oncuechange
oncut
ondblclick
ondrag
ondragend
ondragenter
ondragexit
ondragleave
ondragover
ondragstart
ondrop
ondurationchange
onemptied
onended
onerror
onfocus
oninput
oninvalid
onkeydown
onkeypress
onkeyup
onload
onloadeddata
onloadedmetadata
onloadstart
onmousedown
onmouseenter
onmouseleave
onmousemove
onmouseout
onmouseover
onmouseup
onpaste
onpause
onplay
onplaying
onprogress
onratechange
onreset
onresize
onscroll
onseeked
onseeking
onselect
onshow
onstalled
onsubmit
onsuspend
ontimeupdate
ontoggle
onvolumechange
onwaiting
onwheel
presentation attributes
deprecated xlink attributes
xlink:href
xlink:title
href
target
ping
rel
hreflang
type
referrerpolicy
DOM Interfaces:
SVGAElement
Attribute definitions:
Name
Value
Initial value
Animatable
href
URL
[URL]
(none)
yes
The location of the referenced object, expressed as an
URL reference
Refer to the common handling defined for
URL reference attributes
Name
Value
Initial value
Animatable
target
_self | _parent | _top | _blank |
_self
yes
This attribute should be used when there are multiple possible targets for
the ending resource, such as when the parent document is embedded within an HTML
or XHTML document, or is viewed with a tabbed browser. This attribute specifies the
name of the browsing context
(e.g., a browser tab or an (X)HTML iframe or object element) into
which a document is to be opened when the link is activated:
_self
The current SVG image is replaced by the linked content in the
same browsing context as the current SVG image.
_parent
The immediate parent browsing context of the SVG image is replaced by the
linked content, if it exists and can be securely accessed from this document.
_top
The content of the full active window or tab is replaced by the linked content,
if it exists and can be securely accessed from this document
_blank
A new un-named window or tab is requested for the display of the
linked content, if this document can securely do so.
If the user agent does not support multiple windows/tabs,
the result is the same as
_top

Specifies the name of the browsing context (tab, inline frame, object, etc.)
for display of the linked content. If a context with this name
already exists, and can be securely accessed from this document, it is re-used,
replacing the existing content. If it does not exist, it is created
(the same as
'_blank'
, except that
it now has a name). The name must be a valid XML Name [XML11], and should not start
with an underscore (U+005F LOW LINE character), to meet the requirements of a
valid
browsing context name
from HTML.
The normative definitions for browsing contexts and security
restrictions on navigation actions between browsing contexts
is HTML [
HTML
], specifically
the chapter on
loading web pages
Previous versions of SVG defined the special target value
'_replace'
. It was never well implemented,
and the distinction between
'_replace'
and
'_self'
has been made redundant by
changes in the HTML definition of browsing contexts. Use
'_self'
to replace the current
SVG document.
The value
'_new'
is
not
legal value for target. Use
'_blank'
to open a document in a new tab/window.
Name
Value
Initial value
Animatable
any value (if non-empty, value represents a suggested file name)
(none)
no
ping
space-separated valid non-empty URL tokens
[HTML]
(none)
no
rel
space-separated keyword tokens
[HTML]
(none)
no
hreflang
A BCP 47 language tag string
[HTML]
(none)
no
type
A MIME type string
[HTML]
(none)
no
referrerpolicy
A referrer policy string
[REFERRERPOLICY]
(none)
no
These attributes further describe the targetted resource
and its relationship to the current document.
Allowed values and meaning are
as defined for the
element in HTML
16.3. Linking into SVG content: URL fragments and SVG views
Because SVG content often represents a picture or drawing
of something, a common need is to link into a particular
view
of the document, where a view indicates
the initial transformations so as to present a closeup of a particular
section of the document.
16.3.1. SVG fragment identifiers
SVG 2 Requirement:
Merge the SVG 1.1 SE text and the SVG Tiny 1.2 text on fragment identifiers link traversal and add media fragments.
Resolution:
SVG 2 will have media fragment identifiers.
Purpose:
To align with Media Fragments URI.
Owner:
Cyril (
ACTION-3442
To link into a particular view of an SVG document, the
URL reference with fragment
identifier
needs to be a correctly formed
SVG
fragment identifier
. An SVG fragment identifier defines the
meaning of the "selector" or "fragment identifier" portion of URLs that
locate resources of MIME media type "image/svg+xml".
An SVG fragment identifier can come in the following forms:
Shorthand
bare name
form of addressing (e.g.,
MyDrawing.svg#MyView
). This form of
addressing, which allows addressing an SVG element by its ID, is compatible
with the fragment addressing mechanism for older versions of HTML.
An
SVG view specification
(e.g.,
MyDrawing.svg#svgView(viewBox(0,200,1000,1000))
).
This form of addressing specifies the desired view of the
document (e.g., the region of the document to view, the
initial zoom level) completely within the SVG fragment
specification. The contents of the SVG view specification are defined in
SVG fragment identifiers definitions
section.
Basic media fragments identifiers
of type spatial or temporal
(e.g.,
MyDrawing.svg#xywh=0,200,1000,1000 or MyAnimation.svg#t=10)
as defined in [
Media Fragments URI 1.0 (basic)
] and possibly combined using the & sign (e.g.
MyDrawing.svg#xywh=0,200,1000,1000&t=10
).
16.3.2. SVG fragment identifiers definitions
An SVG fragment identifier is defined as follows:
SVGFragmentIdentifier ::= BareName *( "&"
timesegment
) |
SVGViewSpec *( "&"
timesegment
) |
spacesegment
*( "&" timesegment ) |
timesegment
*( "&" spacesegment )

BareName ::= XML_Name
SVGViewSpec ::= 'svgView(' SVGViewAttributes ')'
SVGViewAttributes ::= SVGViewAttribute |
SVGViewAttribute ';' SVGViewAttributes

SVGViewAttribute ::= viewBoxSpec |
preserveAspectRatioSpec |
transformSpec
viewBoxSpec ::= 'viewBox(' ViewBoxParams ')'
preserveAspectRatioSpec = 'preserveAspectRatio(' AspectParams ')'
transformSpec ::= 'transform(' TransformParams ')'
where:
ViewBoxParams
corresponds to the
parameter values for the
viewBox
attribute on the
view
element. For example,
viewBox(0,0,200,200)
AspectParams
corresponds to the
parameter values for the
preserveAspectRatio
attribute on the
view
element. For example,
preserveAspectRatio(xMidYMid)
TransformParams
corresponds to the
parameter values for the
transform
property that is available on
many elements. For example,
transform(scale(5))
Currently additional transform styles and parameters (e.g. transform-origin, perspective) are not supported.
SVG view box parameters are applied in order, as defined in
CSS Transforms
specification (e.g. SVG view is transformed as defined in
ViewBoxParams
then as defined in
TransformParams
).
Spaces are allowed in fragment specifications. Commas
are used to separate numeric values within an SVG view specification
(e.g.,
#svgView(viewBox(0,0,200,200))
and semicolons are used to separate attributes (e.g.,
#svgView(viewBox(0,0,200,200);preserveAspectRatio(none))
).
Fragment identifiers may be url-escaped according to the rules defined in
CSS Object Model (CSSOM)
specification.
For example semicolons can be escaped as %3B to allow animating a (semi-colon separated) list of URLs because otherwise the semicolon would
be interpreted as a list separator.
The four types of
SVGViewAttribute
may occur
in any order, but each type may only occur at most one time in a correctly
formed
SVGViewSpec
When a source document performs a link into an SVG document, for example
via an
HTML anchor element
([
HTML
]; i.e.,

element in HTML) or an
XLink specification [
xlink
], then
the SVG fragment identifier specifies the initial view into the SVG document,
as follows:
If no SVG fragment identifier is provided (e.g, the specified URL did
not contain a "#" character, such as
MyDrawing.svg
),
then the initial view into the SVG document is established using the view
specification attributes (i.e.,
viewBox
, etc.) on the
outermost svg element
If the SVG fragment identifier addresses a
space segment
(e.g.,
MyDrawing.svg#xywh=0,0,100,100
),then the initial
view into the SVG document is established using the view specification attributes
on the
outermost svg element
where the 'viewBox' is overriden by the
x, y, width and height values provided by the fragment identifier.
Media fragments can be specified as "pixel:" (default) and "percent:". In the latter case the resulting 'viewBox' transformation is
calculated against referenced SVG resolved size (width and height). When the host document cannot resolve the width and height of the SVG document,
the used values for width and height should be calculated according to CSS rules for
calculating width and ratio for inline replaced elements
If the SVG fragment identifier addresses a
time segment
(e.g.,
MyDrawing.svg#t=10
),then the initial
view into the SVG document is established as if no fragment identifier was
provided. The rendering of the SVG Document shall be as if the setCurrentTime
method on the SVG Document element had been called with the begin time value
from the fragment identifier. Additionally, if an end time value is provided
in the fragment identifier, the effect is equivalent to calling the pauseAnimations
method on the SVG Document when the document time reaches the end time of the
fragment identifier.
If the SVG fragment identifier addresses a
view
element within
an SVG document (e.g.,
MyDrawing.svg#MyView
then the root
svg
element is displayed in the SVG viewport.
Any view specification attributes included on the given
view
element override the corresponding view specification attributes on the
root
svg
element.
If the SVG fragment identifier addresses specific SVG view (e.g.,
MyDrawing.svg#svgView(viewBox(0,200,1000,1000))
),
then the document fragment defined by the root
svg
element is displayed in the SVG viewport using the SVG view specification
provided by the SVG fragment identifier. Parameters of the svgView specification override
the parameters defined on the root
svg
element of the referenced document.
Unspecified parameters of the svgView specification don't reset the values defined on the root
svg
element of the referenced document.
If the SVG fragment identifier addresses a combination of the above
non-time related identifiers with a time-related identifier (i.e. a timesegment),
the behavior of each identifier is applied.
16.3.3. Predefined views: the
‘view’
element
The
‘view’
element is defined as follows:
view
Categories:
None
Content model:
Any number of the following elements, in any order:
animation elements
animate
animateMotion
animateTransform
set
descriptive elements
desc
title
metadata
script
style
Attributes:
aria attributes
aria-activedescendant
aria-atomic
aria-autocomplete
aria-busy
aria-checked
aria-colcount
aria-colindex
aria-colspan
aria-controls
aria-current
aria-describedby
aria-details
aria-disabled
aria-dropeffect
aria-errormessage
aria-expanded
aria-flowto
aria-grabbed
aria-haspopup
aria-hidden
aria-invalid
aria-keyshortcuts
aria-label
aria-labelledby
aria-level
aria-live
aria-modal
aria-multiline
aria-multiselectable
aria-orientation
aria-owns
aria-placeholder
aria-posinset
aria-pressed
aria-readonly
aria-relevant
aria-required
aria-roledescription
aria-rowcount
aria-rowindex
aria-rowspan
aria-selected
aria-setsize
aria-sort
aria-valuemax
aria-valuemin
aria-valuenow
aria-valuetext
role
core attributes
id
tabindex
autofocus
lang
xml:space
class
style
global event attributes
oncancel
oncanplay
oncanplaythrough
onchange
onclick
onclose
oncopy
oncuechange
oncut
ondblclick
ondrag
ondragend
ondragenter
ondragexit
ondragleave
ondragover
ondragstart
ondrop
ondurationchange
onemptied
onended
onerror
onfocus
oninput
oninvalid
onkeydown
onkeypress
onkeyup
onload
onloadeddata
onloadedmetadata
onloadstart
onmousedown
onmouseenter
onmouseleave
onmousemove
onmouseout
onmouseover
onmouseup
onpaste
onpause
onplay
onplaying
onprogress
onratechange
onreset
onresize
onscroll
onseeked
onseeking
onselect
onshow
onstalled
onsubmit
onsuspend
ontimeupdate
ontoggle
onvolumechange
onwaiting
onwheel
viewBox
preserveAspectRatio
DOM Interfaces:
SVGViewElement
We have resolved to remove viewTarget attribute.
Resolution: Paris 2015 F2F Day 3.
Owner: BogdanBrinza.
16.4. DOM interfaces
16.4.1. Interface SVGAElement
An
SVGElement
object represents an
element in the DOM.
Exposed
=Window]
interface
SVGAElement
SVGGraphicsElement
SameObject
] readonly attribute
SVGAnimatedString
target
attribute DOMString
attribute USVString
ping
attribute DOMString
rel
SameObject
PutForwards
=value] readonly attribute
DOMTokenList
relList
attribute DOMString
hreflang
attribute DOMString
type