Network Working Group
Internet Architecture Board (IAB)                            N. Brownlee
Internet-Draft
Request for Comments: 7996                    The University of Auckland
Intended status:
Category: Informational                                       IAB
Expires: August 29, 2016                               February 26,                                    December 2016
ISSN: 2070-1721

                   SVG Drawings for RFCs: SVG 1.2 RFC
                          draft-iab-svg-rfc-02

Abstract

   .  Maybe the text in section

   This document specifies SVG 1.2 RFC - -- an SVG profile for use in
   diagrams that may appear in RFCs - -- and considers some of the issues
   concerning the creation and use of such diagrams.

Status of This Memo

   This Internet-Draft document is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Engineering
   Task Force (IETF).  Note Architecture Board (IAB)
   and represents information that other groups may also distribute
   working documents as Internet-Drafts.  The list the IAB has deemed valuable to
   provide for permanent record.  It represents the consensus of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid the
   Internet Architecture Board (IAB).  Documents approved for
   publication by the IAB are not a maximum candidate for any level of Internet
   Standard; see Section 2 of RFC 7841.

   Information about the current status of six months this document, any errata,
   and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on August 29, 2016.
   http://www.rfc-editor.org/info/rfc7996.

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   document authors.  All rights reserved.

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Table of Contents

   1. Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2 ....................................................2
   2. SVG 1.2 RFC: An SVG profile Profile for RFCs  . . . . . . . . . . . .   3 ............................3
      2.1. Elements, properties Properties, and attributes allowed Attributes Allowed in
           SVG 1.2 RFC . . . . . . . . . . . . . . . . . . . . . . . . . . .   4 ................................................4
   3. How to create Create SVG drawings  . . . . . . . . . . . . . . . . .   6 Drawings ......................................7
   4. Accessibility Considerations  . . . . . . . . . . . . . . . .   7 ....................................7
   5. Examples of diagrams common Diagrams Common in RFCs . . . . . . . . . . . . .   8 .............................8
      5.1. Packet Layout Diagrams  . . . . . . . . . . . . . . . . .   8 .....................................8
      5.2. Sequence Diagrams (1) . . . . . . . . . . . . . . . . . .   8 ......................................8
      5.3. Sequence Diagrams (2) . . . . . . . . . . . . . . . . . .   8 ......................................8
   6.  IANA Security Considerations . . . . . . . . . . . . . . . . . . . . .   8 .........................................8
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   8
   9. References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     9.1. ......................................................9
      7.1. Normative References  . . . . . . . . . . . . . . . . . .  10
     9.2. .......................................9
      7.2. Informative References  . . . . . . . . . . . . . . . . .  11 .....................................9
   Appendix A. RELAX NG Compact (rnc) (RNC) Schema for SVG 1.2 RFC  . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  53 .........11
   IAB Members at the Time of Approval ...............................53
   Acknowledgements ..................................................53
   Author's Address ..................................................53

1.  Introduction

   Over the last few years years, the RFC Editor has worked with the Internet
   community to develop specifications for changes in the format of
   RFCs.  An outline of the resulting specifications was published as
   [RFC6949] in May 2013.  Since then then, a Design Team has been working
   with the RFC Editor to flesh out those specifications.  One aspect of
   the changes is to allow line drawings in RFCs; [RFC6949] says

      "Graphics

      Graphics may include ASCII art and a more complex form to be
      defined, such as SVG line art [SVG].  Color and grayscale will not
      be accepted.  RFCs must correctly display in monochromatic black-
      and-white to allow for monochrome displays, black-and-white
      printing, and support for visual disabilities." disabilities.

   SVG (Scalable Vector Graphics) has been developed by W3C, the World
   Wide Web Consortium; its current standard is SVG 1.1 Full
   [W3C.REC-SVG11-20110816].  This document defines SVG 1.2 RFC, an SVG
   profile (i.e. (i.e., a subset of SVG) that is suitable for RFC line
   drawings.

   Note that in RFCs, the text provides normative descriptions of
   protocols, systems, etc.  Diagrams may be used to help explain
   concepts more clearly, but they provide supporting detail, details and should
   not be considered to be complete specifications in themselves.

   The details (particularly any vocabularies) described in this
   document are expected to change based on experience gained in
   implementing the RFC production center's toolset. new publication toolsets.  Revised documents will be
   published capturing those changes as the toolset is toolsets are completed.
   Other implementors implementers must not expect those changes to remain backwards-compatible backwards-
   compatible with the details described in this document.

2.  SVG 1.2 RFC: An SVG profile Profile for RFCs

   As a starting point for SVG 1.2 RFC, the Design Team decided to use
   SVG 1.2 Tiny 1.2 (also referred to as "SVG 1.2 Tiny")
   [W3C.REC-SVGTiny12-20081222].  SVG 1.2 Tiny is an SVG subset intended
   to be implemented on small, mobile devices such as
   cellphones cell phones and
   smartphones.  That should allow RFCs to be rendered well on such
   devices, especially those that have small screens.  However, RFCs are
   self-contained documents that do not change once they are published.
   The use of SVG drawings in RFCs is intended to allow authors to
   create drawings that are simple to produce, produce and are easier to
   understand than our traditional 'ASCII Art' "ASCII art" ones.  In short, we are
   also trying to improve access to the content in RFCs, so SVG drawings
   need to be kept as simple as possible.

   Appendix A (below) provides a complete RELAX NG Compact (rnc) (RNC) schema
   [RNG-HOME] for SVG 1.2 RFC.  It is derived from the SVG 1.2 schema,
   and is the formal definition of SVG 1.2 RFC.  The remainder of this
   section gives a simplified - i.e. -- i.e., easier to read and dunderstand - understand --
   overview of SVG 1.2 RFC.

   SVG can provide a complete User Interface, but within RFCs, all we
   need are simple diagrams that do not change once the RFC is
   published.  Therefore, SVG 1.2 RFC does not allow anything from the
   following sections in SVG Tiny 1.2 [W3C.REC-SVGTiny12-20081222]:

   12  Multimedia
   13  Interactivity
   15  Scripting
   16  Animation
   18  Metadata
   19  Extensibility

   Note that SVG Tiny 1.2 elements may have many properties or
   attributes that are needed to support aspects of the above sections.
   Those are not allowed in SVG 1.2 RFC.

   Considering the

   We now consider these other sections in SVG Tiny 1.2
   [W3C.REC-SVGTiny12-20081222]:

    9 Basic Shapes

   10 Text
        Everything in these sections this section is allowed in SVG 1.2 RFC.

   11 Painting: Filling, Stroking, Colors and Paint Servers
        Anything relating to 'color' is not allowed in SVG 1.2 RFC, RFC;
        everything else is allowed.  This is a requirement documented in
        [RFC6949].

   14 Linking
        SVG Tiny 1.2 allows internationalized IRIs Internationalized Resource Identifiers
        (IRIs) in references.  In SVG 1.2 RFC RFC, such links must be ASCII
        only.  That should not cause problems, since one can just use
        the URI form of any IRI.  Authors should try to use links only
        to URIs that are long-term stable.

   17 Fonts
        SVG 1.2 RFC only allows 'serif', 'sans-serif' 'sans-serif', and 'monospace'
        generic font families from the WebFonts facility, described in
        CSS 2.1, [W3C.REC-CSS2-20110607], section 15, Fonts.
        Section 15 ("Fonts") of the W3C Cascading Style Sheets (CSS) 2.1
        document [W3C.REC-CSS2-20110607].  In particular, the SVG 'font'
        element is not allowed.

2.1.  Elements, properties Properties, and attributes allowed Attributes Allowed in SVG 1.2 RFC

   Elements, properties

   This section discusses elements, properties, and attributes selected
   for SVG 1.2 RFC from [W3C.REC-SVGTiny12-20081222].

   In the list below, elements and properties are listed on the
  left,and
   left, and their allowed values are given in parentheses on the
   right.

   <color> is the list of allowed colors, a black-and-white
           subset of the SVG color names.

   <style> is a set of CSS attributes that are commonly used (by SVG
           drawing applications).  They are not part of SVG Tiny 1.2, 1.2
           but are included here for compatibility.  Note that

           - There is no guarantee that any renderer will implement
             all the CSS attributes a drawing application may use.

           - Authors will need to consider the compatibility of their
             drawings with rendering devices.

   Elements:

     svg              (version=1.2, baseProfile=tiny, width, viewBox,
                       preserveAspectRatio, snapshotTime, height,
                       id, role)
     g                (label, class, id, role, fill, <style>, transform)
     defs             (id, role, fill)
     title            (id, role)
     desc             (id, role)
     a                (id, role, fill, transform)
     use              (x, y, href, xlink:href, id, role,
                       fill, transform)

     rect             (x, y, width, height, rx, ry, stroke-miterlimit stroke-miterlimit,
                       id, role, fill, <style>, transform)
     circle           (cx, cy, r, id, role, fill, <style>, transform)
     ellipse          (cx, cy, rx, ry, id, role,
                       fill, <style>, transform)
     line             (x1, y1, x2, y2, id, role, fill, transform)
     polyline         (points, id, role, fill, transform)
     polygon          (points, id, role, fill, <style>, transform)
     text             (x, y, rotate, space, id, role, fill, <style>,
                       transform)
     tspan            (x, y, id, role, fill)
     textArea         (x, y, width, height, auto, id, role, fill,
                       transform)
     tbreak           (id, role)

     solidColor       (id, role, fill)
     linearGradient   (gradientUnits, x1, y1, x2, y2, id, role, fill)
     radialGradient   (gradientUnits, cx, cy, r, id, role, fill)
     stop             (id, role, fill)
     path             (d, pathLength, stroke-miterlimit,
                       id, role, fill, <style>, transform)

   Properties: (most allow inherit "inherit" as a value)

     <style>          (font-family, font-weight, font-style,
                       font-variant, direction, unicode-bidi,
                       text-anchor, fill, fill-rule)

     <color>          (black, white, #000000, #ffffff, #FFFFFF)

     stroke           (<color>, none, currentColor)
     stroke-width
     stroke-linecap   (butt, round, square)
     stroke-linejoin  (miter, round, bevel)
    stroke-mitrelimit
     stroke-miterlimit
     stroke-dasharray
     stroke-dashoffset
     stroke-opacity
     vector-effect    (non-scaling-stroke, none)
     viewport-fill    (none, currentColor)
     viewport-fill-opacity

     display          (inline, block, list-item, run-in, compact,
                       marker, table, inline-table, table-row-group,
                       table-header-group, table-footer-group,
                       table-row, table-column-group,
                       table-column, table-cell, table-caption,
                       none)
     visibility       (visible, hidden, collapse)
     color-rendering  (auto, optimizeSpeed, optimizeQuality)
     shape-rendering  (auto, optimizeSpeed, crispEdges,
                       geometricPrecision)
     text-rendering   (auto, optimizeSpeed, optimizeLegibility,
                       geometricPrecision)
     buffered-rendering  (auto, dynamic, static)

     opacity
     solid-opacity
     solid-color    (currentColor, <color>)
     color          (currentColor, <color>)
     stop-color     (currentColor, <color>)
     stop-opacity

     line-increment (auto)
     text-align     (start,end,     (start, end, center)
     display-align  (auto, before, center, after)

     font-size
     font-family    (serif, sans-serif, monospace)
     font-weight    (normal, bold, bolder, lighter)
     font-style     (normal, italic, oblique)
     font-variant   (normal, small-caps)
     direction      (ltr, rtl)
     unicode-bidi   (normal, embed, bidi-override)
     text-anchor    (start, middle, end)
     fill           (none, <color>)
     fill-rule      (nonzero, evenodd)
     fill-opacity

3.  How to create Create SVG drawings Drawings

   Many drawing packages can be used to create SVG drawings, drawings -- for example
   example, Open Source packages Inkscape and Dia.  Be aware that such
   packages may use SVG elements or attributes that are not allowed in
   SVG 1.2 RFC.

   o  For example, the 'marker' attribute is often used to place symbols
      such as arrowheads on lines, but 'marker' is not allowed in
      SVG 1.2 Tiny or SVG 1.2 RFC.  In such cases cases, one has to draw the
      arrowhead in another, simpler way.

   o  SVG clip paths are used to define a shape; objects outside that
      shape become invisible.  The 'clipPath' element is not allowed in
      SVG 1.2 Tiny or SVG 1.2 RFC.

   Diagrams produced with these packages may contain elements, their
   attributes or properties, or values of attributes or properties that
   are not allowed in SVG 1.2 RFC.  We will need to provide a tool to
   either (1) strip out anything that is not allowed in SVG 1.2 RFC, RFC or to
   (2) replace disallowed values, e.g., 'sans-serif' for values (e.g., replace 'Sans' with 'sans-serif'
   as values an allowed value for 'font-
   family'. 'font-family').  Experience with a simple
   test version of a tool for this has shown that such deletion and
   replacement can be effective for making SVG files from drawing
   packages conform to SVG 1.2 RFC, without visibly changing the
   diagrams they produce.

   The tool described above can also be used by Authors authors simply to check
   that their diagrams conform to SVG 1.2 RFC.  To help with this, if
   visible changes do occur, the tool should produce a list of non-
   allowed
   non-allowed keywords and the context in which they were found.

   To include a diagram into in an RFC, the xml2rfc (v3) tool will need to
   provide a way to include SVG drawings in Internet Drafts, Internet-Drafts, as
   described in [XML2RFCv3] sections Section 2.5 and 2.67. of [RFC7991].

4.  Accessibility Considerations

   One of the long-term goals for RFCs is to make them more accessible,
   e.g.
   e.g., to sight-impaired readers.  For diagrams, it would be useful
   for authors to provide alternative forms of the diagram, so that voice-
   reading
   voice-reading software could be used to 'talk through' "talk through" the diagram.
   Simply reading the SVG code for a complex diagram seems unlikely
   to work.

   SVG 1.2 RFC allows SVG's 'title' and 'desc' elements.  'title'
   provides a brief text caption for an SVG object (much like a figure
   caption), and 'desc' provides a longer text description of what the
   object actually represents.  As well, the SVG 'role' attribute can be
   used to indicate to a browser how an SVG object is to be interpreted.
   Good suggestions on how to use these elements are given in
   [SVG-ACCESS-TIPS].

   ARIA is a W3C Recommendation for using SVG to create 'Accessible (as the name
   "ARIA" indicates) "Accessible Rich Internet Applications.' Applications".  A helpful
   introduction to ARIA is provided by [SVG-ARIA-PRIMER], while
   [SVG-USING-ARIA] gives examples of how to use ARIA to enhance SVG
   accessibility.

5.  Examples of diagrams common Diagrams Common in RFCs

   Another way to create SVG drawings is to write programs to draw them.
   For example, using python Python and its svgwrite module is a pleasant
   environment (for those who like writing code); this section presents
   a few examples of diagrams created in this way.  Note that they are
   merely examples of typical diagrams from RFCs.

   The SVG diagrams for this section can be seen at
   [This-I-D-with-SVG-included] section, along with an html HTML version of this draft
   document that includes the SVG diagrams. diagrams, can be seen at
   [NB-SVG-1.2-RFC].

5.1.  Packet Layout Diagrams

   Example: Figure 3 from [RFC0793]. [RFC793].

5.2.  Sequence Diagrams (1)

   Example: Figure 6 from [ExpTrustedProxy].

5.3.  Sequence Diagrams (2)

   Example: Figure 3 from [RFC4321].

6.  IANA  Security Considerations

   This document does not create a new registry nor does it register introduce any
   values in existing registries; no IANA action is required.

9. security considerations on
   its own.

7.  References

9.1.

7.1.  Normative References

   [RFC6949]  Flanagan, H. and N. Brownlee, "RFC Series Format
              Requirements and Future Development", RFC 6949,
              DOI 10.17487/RFC6949, May 2013,
              <http://www.rfc-editor.org/info/rfc6949>.

   [W3C.REC-SVGTiny12-20081222]
              Andersson, O., Berjon, R., Dahlstrom, E., Emmons, A.,
              Ferraiolo, J., Grasso, A., Hardy, V., Hayman, S., Jackson,
              D., Lilley, C., McCormack, C., Neumann, A., Northway, C.,
              Quint, A., Ramani, N., Schepers, D., and A. Shellshear,
              "Scalable Vector Graphics (SVG) Tiny 1.2 Specification",
              World Wide Web Consortium Recommendation REC-
              SVGTiny12-20081222,
              REC-SVGTiny12-20081222, December 2008,
              <http://www.w3.org/TR/2008/REC-SVGTiny12-20081222>.

   [W3C.REC-CSS2-20110607]
              Bos, B., Celik, T., Hickson, I., and H. Lie, "Cascading
              Style Sheets Level 2 Revision 1 (CSS 2.1) Specification",
              World Wide Web Consortium Recommendation REC-
              CSS2-20110607,
              REC-CSS2-20110607, June 2011,
              <http://www.w3.org/TR/2011/REC-CSS2-20110607>.

9.2.

7.2.  Informative References

   [W3C.REC-SVG11-20110816]
              Dahlstrom, E., Dengler, P., Grasso, A., Lilley, C.,
              McCormack, C., Schepers, D., Watt, J., Ferraiolo, J.,
              Fujisawa, J., and D. Jackson, "Scalable Vector Graphics
              (SVG) 1.1 (Second Edition)", World Wide Web Consortium
              Recommendation REC-SVG11-20110816, August 2011,
              <http://www.w3.org/TR/2011/REC-SVG11-20110816>.

   [SVG-ACCESS-TIPS]
              Watson, L., "Tips for Creating Accessible SVG", SitePoint
              tips-accessible-svg, May 2014,
              <http://www.sitepoint.com/tips-accessible-svg>.

   [SVG-ARIA-PRIMER]
              Pappas, L., Schwerdtfeger, R., and M. Cooper,
              "WAI-ARIA 1.0 Primer", World Wide Web Consortium WD WD-wai-aria-
              primer-20100916,
              Working Draft, September 2010,
              <http://www.w3.org/TR/2010/WD-wai-aria-primer-20100916>.

   [SVG-USING-ARIA]
              Watson, L., "Using ARIA to enhance SVG accessibility",
              The Paciello Group 2013/12/using-aria-enhance-svg-
              accessibility, Group, December 2013,
              <http://blog.paciellogroup.com/2013/12/
              using-aria-enhance-svg-accessibility>.

   [XML2RFCv3]
              <https://www.paciellogroup.com/blog/2013/12/
              using-aria-enhance-svg-accessibility/>.

   [RFC7991]  Hoffman, P., "The "xml2rfc" version Version 3 Vocabulary", draft-
              iab-xml2rfc-03 (work in progress), February 2016.

   [This-I-D-with-SVG-included]
              RFC 7991, DOI 10.17487/RFC7991, December 2016,
              <http://www.rfc-editor.org/info/rfc7991>.

   [NB-SVG-1.2-RFC]
              Brownlee, N., "Example html version "Index of this I-D with its
              SVG diagrams included", Nevil's home
              page, https://www.cs.auckland.ac.nz/~nevil/SVG_RFC_1.2,
              October 16 2015.

   [RFC0793] /~nevil/SVG_RFC_1.2",
              <https://www.rfc-editor.org/materials/format/svg/>.

   [RFC793]   Postel, J., "Transmission Control Protocol", STD 7,
              RFC 793, DOI 10.17487/RFC0793, September 1981,
              <http://www.rfc-editor.org/info/rfc793>.

   [ExpTrustedProxy]
              Loretto,
              Loreto, S., Mattson, Mattsson, J., Skog, R., Spaak, H., Gus, Bourg, G.,
              Druta, D., and M. Hafeez, "Explicit Trusted Proxy in
              HTTP/2.0", Internet Draft draft-loreto-httpbis-trusted-
              proxy20-01, Work in Progress,
              draft-loreto-httpbis-trusted-proxy20-01, February 2014.

   [RFC4321]  Sparks, R., "Problems Identified Associated with the
              Session Initiation Protocol's (SIP) Non-INVITE
              Transaction", RFC 4321, DOI 10.17487/RFC4321,
              January 2006, <http://www.rfc-editor.org/info/rfc4321>.

   [RNG-HOME]
              Murata, M., "RELAX NG home page", February 2014,
              <http://www.relaxng.org/>.

Appendix A.  RELAX NG Compact (rnc) (RNC) Schema for SVG 1.2 RFC

   The following rnc RNC schema can be used to check whether an svg SVG file
   conforms to SVG 1.2 RFC.  For example, if this schema were contained
   in a file called SVG-1.2-RFC.rnc, the following command will test
   whether svg SVG file diagram.svg is a conformant SVG 1.2 RFC drawing.

   jing -c SVG-1.2-RFC.rnc diagram.svg

   The RNC schema included below is available on the RFC Editor website
   <https://www.rfc-editor.org/materials/format/SVG-1.2-RFC.rnc>.  The
   website is considered definitive should there be any discrepancies.

#---  SVG 1.2 RFC rnc RNC schema; Nevil Brownlee, Thu 26 Jan 2016 (NZST)

default namespace = "http://www.w3.org/2000/svg"
namespace ns1 = "http://www.w3.org/1999/xlink"

rfc-color = (  # SVG-1.2-RFC doesn't allow "color color or grey-scale" grayscale
  "black" | "white" | "#000000" | "#FFFFFF" | "#ffffff" | "inherit" )
start = svg
svg =
  element svg {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute width { xsd:string }?,
    attribute height { xsd:string }?,
    attribute preserveAspectRatio {
      xsd:string { pattern = "\s*(none|xMidYMid)\s*(meet)?\s*" }
    }?,
    attribute viewBox { text }?,
    attribute zoomAndPan { "disable" }?,
    attribute version {
      xsd:string "1.2"
    }?,
    attribute baseProfile {
      xsd:string "tiny"
    }?,
    attribute contentScriptType { xsd:string }?,
    attribute snapshotTime { xsd:string "none" | xsd:string }?,
    attribute timelineBegin {
      xsd:string "onLoad" | xsd:string "onStart"
    }?,
    attribute playbackOrder {
      xsd:string "all" | xsd:string "forwardOnly"
    }?,
    (desc
     | svgTitle
     | path
     | rect
     | circle
     | line
     | ellipse
     | polyline
     | polygon
     | solidColor
     | textArea
     | linearGradient
     | radialGradient
     | \text
     | g
     | defs
     | use
     | a)*
  }
desc =
  element desc {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    ((attribute display {
        "inline"
        | "block"
        | "list-item"
        | "run-in"
        | "compact"
        | "marker"
        | "table"
        | "inline-table"
        | "table-row-group"
        | "table-header-group"
        | "table-footer-group"
        | "table-row"
        | "table-column-group"
        | "table-column"
        | "table-cell"
        | "table-caption"
        | "none"
        | "inherit"
      }?,
      attribute visibility { "visible" | "hidden" | "collapse"
        | "inherit" }?,
      attribute image-rendering {
        "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
      }?,
      attribute shape-rendering {
        "auto"
        | "optimizeSpeed"
        | "crispEdges"
        | "geometricPrecision"
        | "inherit"
      }?,
      attribute text-rendering {
        "auto"
        | "optimizeSpeed"
        | "optimizeLegibility"
        | "geometricPrecision"
        | "inherit"
      }?,
      attribute buffered-rendering {
        "auto" | "dynamic" | "static" | "inherit"
      }?)
     & (attribute viewport-fill { "none" | rfc-color }?,
        attribute viewport-fill-opacity { "inherit" | xsd:string }?)),
    text
  }
svgTitle =
  element title {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    ((attribute display {
        "inline"
        | "block"
        | "list-item"
        | "run-in"
        | "compact"
        | "marker"
        | "table"
        | "inline-table"
        | "table-row-group"
        | "table-header-group"
        | "table-footer-group"
        | "table-row"
        | "table-column-group"
        | "table-column"
        | "table-cell"
        | "table-caption"
        | "none"
        | "inherit"
      }?,
      attribute visibility { "visible" | "hidden"
        | "collapse" | "inherit" }?,
      attribute image-rendering {
        "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
      }?,
      attribute shape-rendering {
        "auto"
        | "optimizeSpeed"
        | "crispEdges"
        | "geometricPrecision"
        | "inherit"
      }?,
      attribute text-rendering {
        "auto"
        | "optimizeSpeed"
        | "optimizeLegibility"
        | "geometricPrecision"
        | "inherit"
      }?,
      attribute buffered-rendering {
        "auto" | "dynamic" | "static" | "inherit"
      }?)
     & (attribute viewport-fill { "none" | rfc-color }?,
        attribute viewport-fill-opacity { "inherit" | xsd:string }?)),
    text
  }
path =
  element path {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute d { xsd:string }?,
    attribute pathLength { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle)*
  }
rect =
  element rect {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute x { xsd:string }?,
    attribute y { xsd:string }?,
    attribute width { xsd:string }?,
    attribute height { xsd:string }?,
    attribute rx { xsd:string }?,
    attribute ry { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle)*
  }
circle =
  element circle {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute cx { xsd:string }?,
    attribute cy { xsd:string }?,
    attribute r { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle)*
  }
line =
  element line {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute x1 { xsd:string }?,
    attribute y1 { xsd:string }?,
    attribute x2 { xsd:string }?,
    attribute y2 { xsd:string }?,
    (desc
     | svgTitle)*
  }
ellipse =
  element ellipse {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute rx { xsd:string }?,
    attribute ry { xsd:string }?,
    attribute cx { xsd:string }?,
    attribute cy { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle)*
  }
polyline =
  element polyline {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute points { xsd:string }?,
    (desc
     | svgTitle)*
  }
polygon =
  element polygon {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute transform { xsd:string | "none" }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute points { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle)*
  }
solidColor =
  element solidColor {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    (desc
     | svgTitle)*
  }
textArea =
  element textArea {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute transform { xsd:string | "none" }?,
    attribute x { xsd:string }?,
    attribute y { xsd:string }?,
    attribute width { xsd:string | "auto" }?,
    attribute height { xsd:string | "auto" }?,
    (tspan
     | desc
     | svgTitle
     | tspan_2
     | text
     | a_2)+
  }
linearGradient =
  element linearGradient {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute gradientUnits { "userSpaceOnUse" | "objectBoundingBox" }?,
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute x1 { xsd:string }?,
    attribute y1 { xsd:string }?,
    attribute x2 { xsd:string }?,
    attribute y2 { xsd:string }?,
    (desc
     | svgTitle)*
  }
radialGradient =
  element radialGradient {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute gradientUnits { "userSpaceOnUse" | "objectBoundingBox" }?,
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute cx { xsd:string }?,
    attribute cy { xsd:string }?,
    attribute r { xsd:string }?,
    (desc
     | svgTitle)*
  }
\text =
  element text {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute transform { xsd:string | "none" }?,
    attribute x { xsd:string }?,
    attribute y { xsd:string }?,
    attribute rotate { xsd:string }?,
    attribute style { xsd:string }?,  # Added to SVG-1.2-RFC (Inkscape)
    (desc
     | svgTitle
     | tspan_2
     | text
     | a_2)+
  }
g =
  element g {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute transform { xsd:string | "none" }?,
    attribute style { xsd:string }?,
        # Added to SVG-1.2-RFC (for Inkscape)
    attribute visibility {
      "visible" | "hidden" | "collapse" | "inherit" }?,
        # Added to SVG-1.2-RFC (for LibreOffice)
    (desc
     | svgTitle
     | path
     | rect
     | circle
     | line
     | ellipse
     | polyline
     | polygon
     | solidColor
     | textArea
     | linearGradient
     | radialGradient
     | \text
     | g
     | defs
     | use
     | a)*
  }
defs =
  element defs {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    (desc
     | svgTitle
     | path
     | rect
     | circle
     | line
     | ellipse
     | polyline
     | polygon
     | solidColor
     | textArea
     | linearGradient
     | radialGradient
     | \text
     | g
     | defs
     | use
     | a)*
  }
use =
  element use {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute transform { xsd:string | "none" }?,
    attribute ns1:show { "embed" }?,
    attribute ns1:actuate { "onLoad" }?,
    attribute ns1:type { "simple" }?,
    attribute ns1:role { xsd:anyURI | xsd:string }?,
    attribute ns1:arcrole { xsd:anyURI | xsd:string }?,
    attribute ns1:title { text }?,
    attribute ns1:href { xsd:anyURI | xsd:string }?,
    attribute x { xsd:string }?,
    attribute y { xsd:string }?,
    (desc
     | svgTitle)*
  }
a =
  element a {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute transform { xsd:string | "none" }?,
    attribute ns1:show { "new" | "replace" }?,
    attribute ns1:actuate { "onRequest" }?,
    attribute ns1:type { "simple" }?,
    attribute ns1:role { xsd:anyURI | xsd:string }?,
    attribute ns1:arcrole { xsd:anyURI | xsd:string }?,
    attribute ns1:title { text }?,
    attribute ns1:href { xsd:anyURI | xsd:string }?,
    attribute target {
      "_replace" | "_self" | "_parent" | "_top" | "_blank" | xsd:Name
    }?,
    (desc
     | svgTitle
     | path
     | rect
     | circle
     | line
     | ellipse
     | polyline
     | polygon
     | solidColor
     | textArea
     | linearGradient
     | radialGradient
     | \text
     | g
     | defs
     | use)*
  }
stop =
  element stop {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "inherit" | xsd:string }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { "inherit" | xsd:string }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { "inherit" | xsd:string }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { "inherit" | xsd:string }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute offset { xsd:string }?,
    (desc
     | svgTitle)*
  }
tspan =
  element tspan {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute x { xsd:string }?,  # For SVG-1.2-RFC
    attribute y { xsd:string }?,
    (tbreak
     | desc
     | svgTitle
     | tspan_2
     | text
     | a_2)+
  }
tspan_2 =
  element tspan {
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    attribute x { xsd:string }?,  # For SVG-1.2-RFC
    attribute y { xsd:string }?,
    (desc
     | svgTitle
     | tspan_2
     | text
     | a_2)+
  }
a_2 =
  element a {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?,
    ((attribute fill-opacity { "inherit" | xsd:string }?,
      attribute stroke-opacity { "inherit" | xsd:string }?)
     & (attribute fill { "none" | rfc-color }?,
        attribute fill-rule { "inherit" | "nonzero" | "evenodd" }?,
        attribute stroke { rfc-color }?,
        attribute stroke-dasharray { "inherit" | "none" | xsd:string }?,
        attribute stroke-dashoffset { "inherit" | xsd:string }?,
        attribute stroke-linecap {
          "butt" | "round" | "square" | "inherit"
        }?,
        attribute stroke-linejoin {
          "miter" | "round" | "bevel" | "inherit"
        }?,
        attribute stroke-miterlimit { "inherit" | xsd:string }?,
        attribute stroke-width { "inherit" | xsd:string }?,
        attribute color { rfc-color }?,
        attribute color-rendering {
          "auto" | "optimizeSpeed" | "optimizeQuality" | "inherit"
        }?)
     & attribute vector-effect {
         "none" | "non-scaling-stroke" | "inherit"
       }?
     & (attribute direction { "ltr" | "rtl" | "inherit" }?,
        attribute unicode-bidi {
          "normal" | "embed" | "bidi-override" | "inherit"
        }?)
     & (attribute solid-color { rfc-color }?,
        attribute solid-opacity { "inherit" | xsd:string }?)
     & (attribute display-align {
          "auto" | "before" | "center" | "after" | "inherit"
        }?,
        attribute line-increment { "auto" | "inherit" | xsd:string }?)
     & (attribute stop-color { rfc-color }?,
        attribute stop-opacity { "inherit" | xsd:string }?)
     & (attribute font-family { "inherit" | xsd:string }?,
        attribute font-size { "inherit" | xsd:string }?,
        attribute font-style {
          "normal" | "italic" | "oblique" | "inherit"
        }?,
        attribute font-variant { "normal" | "small-caps" | "inherit" }?,
        attribute font-weight {
          "normal"
          | "bold"
          | "bolder"
          | "lighter"
          | "inherit"
        }?,
        attribute text-anchor {
          "start" | "middle" | "end" | "inherit"
        }?,
        attribute text-align {
          "start" | "center" | "end" | "inherit"
        }?)),
    attribute transform { xsd:string | "none" }?,
    attribute ns1:show { "new" | "replace" }?,
    attribute ns1:actuate { "onRequest" }?,
    attribute ns1:type { "simple" }?,
    attribute ns1:role { xsd:anyURI | xsd:string }?,
    attribute ns1:arcrole { xsd:anyURI | xsd:string }?,
    attribute ns1:title { text }?,
    attribute ns1:href { xsd:anyURI | xsd:string }?,
    attribute target {
      "_replace" | "_self" | "_parent" | "_top" | "_blank" | xsd:Name
    }?,
    (desc
     | svgTitle
     | tspan_2
     | text)+
  }
tbreak =
  element tbreak {
    (attribute id { xsd:NCName }
     | attribute xml:id { xsd:NCName })?,
    attribute xml:base { xsd:anyURI | xsd:string }?,
    attribute xml:lang { xsd:language? }?,
    attribute class { xsd:NMTOKENS }?,
    attribute role { xsd:string }?,
    attribute rel { xsd:string }?,
    attribute rev { xsd:string }?,
    attribute typeof { xsd:string }?,
    attribute content { xsd:string }?,
    attribute datatype { xsd:string }?,
    attribute resource { xsd:string }?,
    attribute about { xsd:string }?,
    attribute property { xsd:string }?,
    attribute xml:space { "default" | "preserve" }?,
    attribute requiredFeatures { xsd:string }?,
    attribute requiredExtensions { xsd:string }?,
    attribute requiredFormats { xsd:string }?,
    attribute requiredFonts { xsd:string }?,
    attribute systemLanguage { xsd:string }?
  }

#---  End of SVG 1.2 RFC rnc RNC schema

7.

IAB Members at the Time of Approval

   The IAB members at the time this memo was approved were
   (in alphabetical order):

      Jari Arkko
      Ralph Droms
      Ted Hardie
      Joe Hildebrand
      Russ Housley
      Lee Howard
      Erik Nordmark
      Robert Sparks
      Andrew Sullivan
      Dave Thaler
      Martin Thomson
      Brian Trammell
      Suzanne Woolf

Acknowledgements

   Thanks to the RSE and the Design Team members for their helpful
   comments and suggestions for SVG 1.2 RFC, as well as from RFC.  Thanks also to the wider
   IETF community.

Authors' Addresses community for their input.

Author's Address

   Nevil Brownlee
   The University of Auckland

   Email: n.brownlee@auckland.ac.nz

   Internet Architecture Board

   Email: iab@iab.org