Inlined Images for NCSA Mosaic
Introduction
NCSA Mosaic
supports inlined bitmaps and images in X bitmap and GIF formats. For example, here is a bitmap:
. Here is a bitmap serving as an anchor to another document:
.
How It Works
To embed a bitmap or image in a HTML document, use the IMG tag. For example:
<![CDATA[
<IMG SRC="http://foobar.com/foobar.xbm">
]]>
To use a bitmap or image as an anchor, do something like this:
<![CDATA[
<A HREF="http://foobar.com/blagh.html">
<IMG SRC="http://foobar.com/foobaz.gif">
</A>
]]>
This causes the GIF image named foobar.gif to be used as an anchor to the document named blagh.html. When a bitmap or an image serves as an anchor, it is surrounded by a colored rectangle and made sensitive to mouse clicks, just like ordinary text anchors.
Note that the value of a SRC argument is a
Uniform Resource Locator
--- image data can thus lie anywhere on the network; it is retrieved as the document is being formatted by Mosaic. Once image data has been retrieved once, it is cached in memory, so subsequent uses of the same image will be generally very quick.
For example,
. Using this bitmap (which was also used above) twice in the same document incurred very little additional overhead.
Alignment
You can choose to have inlined images top aligned or bottom aligned with their surrounding text. Here's a top aligned image:
. The next paragraph will begin with a bottom aligned image.
That was a bottom aligned image. Whether an inlined image is top aligned or bottom aligned is determined by the (optional)
ALIGN
attribute to the
IMG
element: the choices are
ALIGN=TOP
and
ALIGN=BOTTOM
(default is top). Here's how image of Dan at the start of this paragraph was specified:
<IMG ALIGN=BOTTOM SRC="../Demo/quayle.xbm">.
Currently, text cannot be made to cleanly flow around an image. This is a known drawback in
HTML
and is due to be corrected in HTML's successor.
Another Demo
OK, now that you sat through that, here's
another demo, this time with color GIF images.
Extensive uses of inlined images can be found
here,
here,
here, and elsewhere.
Acknowledgements
The GIF-reading code NCSA Mosaic uses was written by David Koblas; his copyright statement is
here.
National Center for Supercomputing Applications
mosaic-x@ncsa.uiuc.edu