Proposal for standard icons/symbols

Bert Bos (bert@let.rug.nl)
Fri, 25 Feb 1994 10:25:56 --100


Some time ago there was discussion on this list about defining a set
of standard icons for things like Gopher types, "home" buttons, etc.
The discussion didn't reach a conclusion. Below is a proposal.
Reactions please!

The text and two sets of example icons are also available at:

gopher://gopher.let.rug.nl/00/ftp/pub/Bert/WWWicn.940218
gopher://gopher.let.rug.nl/99/ftp/pub/Bert/ISO-bitmaps.shar.gz
gopher://gopher.let.rug.nl/99/ftp/pub/Bert/Hughes-icons.shar.gz

and a similar FTP address.

<!--======================================================================

Status:
Proposal

File:
WWWicn

Version:
0.0

Formal Public Identifier:
Most recent version:
-//WWW//ENTITIES WWW standard icons//EN

This version:
-//WWW//ENTITIES WWW standard icons:0.0//EN

Description:
A set of entities for common icons

History:
17 Feb 1994 - version 0.0

Rationale:
An HTML document often contains inlined graphic material,
sometimes as decoration, sometimes to convey information that
would be less clear in words. Some of these graphical objects
function much like mathematical or other symbols; they have
become part of the World-Wide Web language. E.g., in Gopher
menus the type of a menu entry is often indicated with such a
symbol.

Traditionally, such symbols have been added to the text by means
of in-lined images. But there has been a demand for
standardization of a small set of symbols which every HTML
browser would be able to recognize and display in some way. It
has been suggested that a naming scheme could be invented whereby
reserved names in <IMAGE> tags would flag to the browser that a
special action was required. Another suggested approach is to use
the (as yet undefined) URN mechanism.

The first solution - reserved names in the attributes of <IMAGE>
tags - has the drawback that it uses a name-space that is not
(and should not be) under the control of HTML. It also requires
browsers that normally ignore in-line images to analyze the tags
for special names.

The URN method has the drawback that it specifies a single,
concrete image, instead of the more abstract symbol, that can
vary according to context (bold, large, 3D, in color, etc.)

The solution in this document uses features of SGML (of which
HTML is a specialization) to abstract away from specific images.
Every symbol is represented by an (external) entity, in much the
same way as other non-ASCII symbols are specified. The HTML+ DTD
would contain something like:

...
<!ENTITY % ISOlat1 PUBLIC "ISO 8879-1986//ENTITIES Added Latin 1//EN">
%ISOlat1;
<!ENTITY % WWWicn PUBLIC "-//WWW//ENTITIES WWW standard icons//EN">
%WWWicn;
<!ENTITY % ISOdia PUBLIC "ISO 8879-1986//ENTITIES Diacritical Marks//EN">
%ISOdia;
...

Notes:
This document defines a number of entities for common icons, such
as "folder", "document", "home" and "sound". Some icons are also
defined in ISO/IEC CD 11581 "icon symbols and functions". Such
icons also have a recommended shape ("ISO SHAPE"), the others
have only suggested shapes ("SHAPE").

A typical HTML application such as a World Wide Web browser will
have its own way of rendering the icons. It may use a collection
of bitmaps in any of the well-known graphics formats, it may have
a special symbol font, or it may try to aproximate the shape with
ASCII characters.

The shapes leave a lot of room for variations. Applications may
use color, shadows, 3D drawings and perhaps even photographs or
holograms to adapt the basic shapes to their own style. The size
of the icons is likewise left unspecified, but it is assumed that
icons are displayed in running text, so they should normally be
no larger than 2 to 4 times the size of a character.

The entities have names of at most 32 characters, which is the
declared NAMELEN of the HTML+ DTD. This precludes using of the
names from ISO-????, since they tend to be longer. The longer
names are shown as a comment where appropriate.

A NOTATION "WWWicn" is declared, but the semantics are
deliberately left undefined. An application that processes HTML
must have its own way of resolving the entity.

References:
1) HTML+ DTD, draft of 24th January 1994

2) ISO/IEC CD 11581 "Information technology - user-system
interfaces - icon symbols and functions" (30 Nov 1993)

=======================================================================-->

<!-- Object icons ========================================================

The icons are not really divided into groups, but indications
such as object icons, navigation icons, etc. make it easier to
document them. The object icons in this section are normally used
to represent objects, not actions. In practice the distinction
may be difficult to make, however.
-->

<!ENTITY folder SDATA "folder">

<!--
Represents a folder or directory or anything that holds other
documents. If an action is associated with it (a hyper-jump or
"open" action), it should gives access to the (table of) contents.

ISO SHAPE: a horizontal rectangle with a small tab sticking out of the
top, near the left side. Reminiscent of folders as used in the office.

ISO NAME: folder
-->

<!ENTITY filing.cabinet SDATA "filing.cabinet">

<!--
...

ISO NAME: filing cabinet
-->

<!ENTITY fixed.disk SDATA "fixed.disk">

<!--
...

ISO NAME: fixed storage device
-->

<!ENTITY disk.drive SDATA "disk.drive">

<!--
...

ISO NAME: drive for removable disk
-->

<!ENTITY document SDATA "document">

<!--
Represents a general document the type of which is unimportant.
When the type is unknown rather than unimportant, it is better to
use the "unknown.document" entity.

ISO SHAPE: a vertical rectangle with a "dog's ear" in the upper
right corner.

ISO NAME: document
-->

<!ENTITY unknown.document SDATA "unknown.document">

<!--
A document of unknown or unrecognized type. If there is an action
associated with this document, it is often an "unsafe" action, in
the sense that the contents may or may not be processable by the
application.

SHAPE: as "document" above, but with a question mark inside.
-->

<!ENTITY text.document SDATA "text.document">

<!--
A document containing (mostly) text, such as text/plain,
text/html, text/enriched, etc.

SHAPE: as "document" above, but with "greeked" text inside
(usually just a few horizontal lines).
-->

<!ENTITY binary.document SDATA "binary.document">

<!--
...
-->

<!ENTITY binhex.document SDATA "binhex.document">

<!--
...
-->

<!ENTITY ftp SDATA "ftp">

<!--
...
-->

<!ENTITY archive SDATA "archive">

<!--
...
-->

<!ENTITY telnet SDATA "telnet">

<!--
...
-->

<!ENTITY form SDATA "form">

<!--
...
-->

<!ENTITY audio SDATA "audio">

<!--
An audio object. "Opening" it should play the sound on the
system's speaker(s) or other audio output equipment.

ISO SHAPE: a stylized loud speaker pointing to the right. (My
suggestion: optionally accompanied by a few semicircular "sound
waves".)

ISO NAME: audio device
-->

<!ENTITY image SDATA "image">

<!--

A photograph, drawing or graphic of any kind. The associated
object might be a file in any still image format, whether in
raster or vector format. "Opening" it should result in the image
being displayed.

SHAPE: a "landscape", e.g., with two shallow mountains and a sun
in the upper left corner.
-->

<!ENTITY map SDATA "map">

<!--

A map, either geographical or a schematic map showing relations
between objects or actions. An interactive map ("hypermap") is
definitily a map, but a non-interactive map might also be
classified as an image. If the purpose of the map to explain or
to instructm then it is probably a map; if it is just an
illustration for other information it is probably an image.

SHAPE: ...
-->

<!ENTITY film SDATA "film">

<!--
A film or animation, such as an MPEG movie. It may have a
soundtrack.

SHAPE: a film projector, pointing right: a rectangle with a large
and a small circle on top and a smaller rectangle representing
the lens.

or: (TBD)

SHAPE: two blank frames from a film reel, with rows of holes
along the left and right side.
-->

<!ENTITY mail SDATA "mail">

<!--
...

ISO NAME: mail
-->

<!-- Navigation icons ====================================================

Icons that represent documents not by their contents, but by
their relation to the document in which they occur. Relations can
be hierarchical: a parent document with children; or linear: a
successor and a predecessor; or semantical: a table of contents,
an index, a glossary, etc.

-->

<!ENTITY parent SDATA "parent">

<!--
Represents the parent of the current document. There should also
be a way to go from the parent back to this child in one step.

SHAPE: a triangle pointing upwards inside a square.
-->

<!ENTITY next SDATA "next">

<!--
The next document in a sequence of documents, such as in an HTML
PATH.

SHAPE: a triangle pointing to the right inside a square.
-->

<!ENTITY previous SDATA "previous">

<!--
The predecessor of the current document in a sequence of
documents.

SHAPE: a triangle pointing to the left inside a square.
-->

<!ENTITY home SDATA "home">

<!--
...
-->

<!ENTITY toc SDATA "toc">

<!--
...
-->

<!ENTITY glossary SDATA "glossary">

<!--
...
-->

<!ENTITY index SDATA "index">

<!--
...
-->

<!ENTITY summary SDATA "summary">

<!--
...
-->

<!-- Miscellaneous =======================================================

-->

-- 
                     _________________________________
                    / _   Bert Bos <bert@let.rug.nl>  |
           ()       |/ \  Alfa-informatica,           |
            \       |\_/  Rijksuniversiteit Groningen |
             \_____/|     Postbus 716                 |
                    |     9700 AS GRONINGEN           |
                    |     Nederland                   |
                    \_________________________________|