FSDL has been updated – so update your sites!

On March 10 the OP3FT released Frogans Player for developers alpha v1.4.1 which uses an updated version of the Frogans Slide Description Language (FSDL).

The changes to FSDL are likely to be the last before the definitive release of the FSDL 3.0 technical specifications. While these changes are not enormous, chances are that you will need to update the Frogans sites that you have already authored for them to work with this and with subsequent versions of Frogans Player.

New attribute values

The changes effecting site compatibility are described in Appendix 3 of the OP3FT document FSDL 3.0 Recap v18 – Elements and Attributes. Essentially, these changes are:

  1. The values of “focus” and “nofocus” for the “visible” attribute in the <layer> element (when that layer is a child of <button>) have been replaced by “selected” and “not-selected,” accordingly. So, this effects every single button in every one of your slides.

  2. The “combine” attribute, is no longer allowed in the <shadow>. Since this was mandatory in previous versions, you will have to update all slides in which <shadow> is present (a child of <setshadow>).

The good news is that, if you miss a few lines when you update an FSDL document and try to open it with Frogans Player, you will get a detailed message telling you where the problem is. For example:


Other new functionalities

“Way-out” links to Web and email

The <button> element now allows a “uri” attribute linking a button to a Web page (via the user device’s Web browser) or for sending an email (via the user device’s email app). This attribute is applicable when the <button>’s “goto” value is “way-out” (also new).

So, if you want a button to link to a secure Web page, your <button> attribute should look something like this:

<button buttonid='mail_b' goto='way-out' uri='https://frogans-addresses.com/' >

Likewise, for the button to open an email app to send a mail to your favorite blogger:

<button buttonid='mail_b' goto='way-out' uri='mailto:[email protected]' >

“Way-out” is pretty cool. There’s even a song about it: https://www.youtube.com/watch?v=BHeoYRXmmlM

“Rules for protecting the interests of end users”

Frogans Player integrates a new set of limitations that are designed to ensure a certain level of usability in all Frogans sites. These limitations, referred to as “rules” are described at length on page 8 of FSDL 3.0 Recap v18 – Elements and Attributes.

  • Network usage rules set the maximum file sizes for FSDL and auxiliary files

  • Processor usage rules limit the number of elements in an FSDL document

  • Memory usage rules limits such things as the cumulative number of pixels in all resource images and the memory required to render them.

  • On-screen usability rules help assure that

    • each Frogans slide is not too small on screen to be usable;

    • every button must have a rollover effect and must be large enough to be easily clicked with a mouse;

    • there is enough non-button surface on the slide for the user to click on it and move the site on the desktop;

Say, for instance, that a given slide uses too many <merge> elements (rendering these apparently takes a lot of memory, relatively speaking). You might get an error message like this:


When this happens, you might want to re-think how you conceived your slide. 2,117,804 bytes might not be a lot for most recent computers, but it could be enough for a lousy user experience on a mid-range phone.

Action item

So don’t wait. Step into the future. Download the new Player alpha, see the havoc that it wreaks on your current Frogans sites and fix these sites so that they’ll work fantastically hereafter and forevermore.

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