Simulacrum is designed to be a slideshow viewer that extracts content from RSS
feeds. The image content is extracted from each RSS item's description tag,
and is displayed in the application window. The application is written with
the capability for editing, removing, or hiding select feeds.
About RSS Feeds
RSS has multiple meanings, either "Really Simple Syndication", or "Rich Site
Summary". There are also multiple concurrent versions of RSS out there, from
0.91 to 2.0. Each format describes one 'channel' with multiple 'item's. The
only way the author managed to accomodate all the concurrent versions of RSS
was to extract only the common elements in the versions. That means an RSS file
with the following structure:
An RSS slide show viewer.About
A verbose description of the Simulacrum project.
This has multiple variations, as well. For example, the tag may not be
inside of the tag, and the main element may be an
element. Also, the content inside of the tag (if it is truly
conforming to the xml standard) is encoded with escape characters, instead of
straight text or HTML.
What Simulacrum Extracts
Now that you know what an RSS feed looks like, we can discuss what the
application looks for inside of the feed.
The application will look inside the feed for any 's
tag that contains an image reference. This may look one of two ways, since the
tag may or may not be escaped. One possible appearance of an
image tag is:
Another possible appearance for the same image could be:
And yet another:
Or, God forbid:
Although, this last one is poorly constructed, because if you escape the '<'
and '>' characters, the '"' should also be escaped.
In all the above cases, the application will extract the URL from the src=""
string, and load that into an image. This is very easy to do in Java. Once
the application has loaded the image, it displays the image, and proceeds to
load the next image or feed.
In addition to the tag, there is also a newer tag, by the name
of . This content tag may also have HTML embedded inside,
with valid image references. This data is tagged onto the back end of the
description tag, so that if there is no valid image URL in the description,
the parser continues searching the data.
In addition to basic slideshow controls, the application enables the toggling
of the feed display, toggling of the menu bar display, toggling of each image's
information, and toggling of the window frame (this feature is not available in
To toggle the display of the feeds, select "Sources / [ ] View Feeds". This
will display a list of the available feeds. While in this view, additional
feed information is available by selecting "Sources / Display >". This will
toggle the visibility of additional columns that contain information extracted
from the RSS feed. If there was an error loading the feed, these columns
will be blank, as the data could not be retrieved.
To toggle the display of the menu bar, simply press and release the right mouse
button once. On Macintosh, hold down the command (squiggly) key, and press the
To toggle the display of image information, select "Image / [ ] Image Info".
This will overlay on the image the RSS and for the image. This
link is clickable in applet mode.
If the application is running, it is possible to turn off the window frame
(title bar and borders). To do so, select "Main / [x] Framed". This will
cause the application window to flicker, and the title bar and borders have
been removed. In order to load them again, enable the checkbox in the menu.