This appendix is normative.
In order to ensure that SVG-family documents are maximally portableamong SVG-family user agents, this specification rigidly definesconformance requirements for both, as well as for SVG-family documenttypes. While the conformance definitions can be found in this appendix,they necessarily reference normative text within this document andwithin other related specifications. It is only possible to fullycomprehend the conformance requirements of SVG through a completereading of all normative references.
An SVG document fragment is aConforming SVG Document Fragment ifit adheres to the specification described in this document(Scalable Vector Graphics (SVG) Specification) and also:
<?xml-stylesheet?>
processing instruction conforms toAssociating stylesheets with XML documents [XML-SS],<?xml version="V" encoding="E"?>
),<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" SYSTEM "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
, andxlink
.SVG document fragments can be included within parent XML documents usingthe XML namespace facilities described inNamespaces in XML [XML-XS].Note, however, that since a Conforming SVG Document Fragment must have an‘svg’ element as its root, the use of an individual non-‘svg’element from the SVG namespace is disallowed. Thus, the SVG part of thefollowing document isnot conforming:
<?xml version="1.0" standalone="no"?><!DOCTYPE SomeParentXMLGrammar PUBLIC "-//SomeParent" "http://SomeParentXMLGrammar.dtd"><ParentXML> <!-- Elements from ParentXML go here --> <!-- The following isnot conforming --> <z:rect xmlns:z="http://www.w3.org/2000/svg" x="0" y="0" width="10" height="10" /> <!-- More elements from ParentXML go here --></ParentXML>
Instead, for the SVG part to become a Conforming SVG Document Fragment,the file could be modified as follows:
<?xml version="1.0" standalone="no"?><!DOCTYPE SomeParentXMLGrammar PUBLIC "-//SomeParent" "http://SomeParentXMLGrammar.dtd"><ParentXML> <!-- Elements from ParentXML go here --> <!-- The following is conforming --> <z:svg xmlns:z="http://www.w3.org/2000/svg" width="100px" height="100px"> <z:rect x="0" y="0" width="10" height="10"/> </z:svg> <!-- More elements from ParentXML go here --></ParentXML>
The SVG language or these conformance criteria provide no designatedsize limits on any aspect of SVG content. There are no maximum values onthe number of elements, the amount of character data, or the number ofcharacters in attribute values.
A file is aConforming SVG Stand-Alone File if:
AConforming SVG Generator is a program which:
Additionally, an authoring tool which is a Conforming SVG Generator conforms to all of the Priority 1 accessibility guidelines from the documentAuthoring Tool Accessibility Guidelines 1.0 [ATAG] that are relevant to generators of SVG content. (Priorities 2 and 3 are encouraged but not required for conformance.)
SVG generators are encouraged to followW3C developments in the area of internationalization. Of particular interest is theW3C Character Model and the concept ofWebwide Early Uniform Normalization, which promises to enhance the interchangability of Unicode character data across users and applications. Future versions of the SVG specification are likely to require support of theW3C Character Model in Conforming SVG Generators.
Conforming SVG Servers must meet all the requirements of a Conforming SVG Generator. In addition, Conforming SVG Servers using HTTP or other protocols that use Internet Media types must serve SVG stand-alone files with the media type"image/svg+xml"
.
Also, if the SVG file is compressed with gzip or deflate, Conforming SVG Servers must indicate this with the appropriate header, according to what the protocol supports. Specifically, for content compressed by the server immediately prior to transfer, the server must use the "Transfer-Encoding: gzip" or "Transfer-Encoding: deflate" headers as appropriate, and for content stored in a compressed format on the server (e.g. with the file extension "svgz"), the server must use the "Content-Encoding: gzip" or "Content-Encoding: deflate" headers as appropriate.
Note: Compression of storedcontent (the "entity," in HTTP terms) is distinct from automatic compression of themessage body, as defined in HTTP/1.1TE/Transfer Encoding ([RFC2616], sections 14.39 and 14.41).
A DOM subtree rooted at a given element is aConforming SVG DOM Subtreeif, once serialized to XML, is aConforming SVG Document Fragment.If the DOM subtree cannot be serialized to XML, such as when aComment node's data contains the substring "--", then the subtree is nota Conforming SVG DOM Subtree.
An SVG interpreter is a program which can parse and process SVG document fragments. Examples of SVG interpreters are server-side transcoding tools (e.g., a tool which converts SVG content into modified SVG content) or analysis tools (e.g., a tool which extracts the text content from SVG content). AnSVG viewer also satisfies the requirements of an SVG interpreter in that it can parse and process SVG document fragments, where processing consists of rendering the SVG content to the target medium.
In aConforming SVG Interpreter, the XML parser must be able to parse and process all XML constructs defined withinXML 1.0 [XML10] andNamespaces in XML [XML-NS].
There are two sub-categories ofConforming SVG Interpreters:
A Conforming SVG Interpreter must parse any SVG document correctly. It is not required to interpret the semantics of all features correctly.
Note: A transcoder from SVG into another graphics representation, such as an SVG-to-raster transcoder, represents a viewer, and thus viewer conformance criteria apply. (SeeConforming SVG Viewers.)
An SVG viewer is a program which can parse and process an SVG document fragment and render the contents of the document onto some sort of output medium such as a display or printer; thus, anSVG Viewer is also anSVG Interpreter.
There are two sub-categories ofConforming SVG Viewers:
Specific criteria that apply to bothConforming Static SVG Viewers andConforming Dynamic SVG Viewers:
Although anti-aliasing support is not a strict requirement for a Conforming SVG Viewer, it is highly recommended for display devices. Lack of anti-aliasing support will generally result in poor results on display devices.
Specific criteria that apply to onlyConforming Dynamic SVG Viewers:
TheWeb Accessibility Initiative is definingUser Agent Accessibility Guidelines 1.0 [UAAG]. Viewers are encouraged to conform to the Priority 1 accessibility guidelines defined in this document, and preferably also Priorities 2 and 3. Once the guidelines are completed, a future version of this specification is likely to require conformance to the Priority 1 guidelines in Conforming SVG Viewers.
A higher order concept is that of aConforming High-Quality SVG Viewer, with sub-categoriesConforming High-Quality Static SVG Viewer andConforming High-Quality Dynamic SVG Viewer.
Both aConforming High-Quality Static SVG Viewer and aConforming High-Quality Dynamic SVG Viewer must support the following additional features:
AConforming High-Quality Dynamic SVG Viewer must support the following additional features:
AConforming SVG Viewer must be able to apply styling properties to SVG content usingpresentation attributes.
If the user agent supportsCascading Style Sheets, level 2 [CSS2], aConforming SVG Viewer must support CSS styling of SVG content and must support all features from CSS2 that are described in this specification as applying to SVG (seeproperties shared with CSS and XSL,Styling with CSS andFacilities from CSS and XSL used by SVG). The supported features from CSS2 must be implemented in accordance with theconformance definitions from the CSS2 specification ([CSS2], section 3.2).
If the user agent includes an HTML or XHTML viewing capability or can apply CSS/XSL styling properties to XML documents, then aConforming SVG Viewer must support resources of MIME type "image/svg+xml" wherever raster image external resources can be used, such as in the HTML or XHTML‘img’ element and in CSS/XSL properties that can refer to raster image resources (e.g.,‘background-image’).