Sunday 27 March 2022

SVG Family-Tree Generator (v6.3)

 

This post announces the release of SVG-FTG V6.3. Details on availability can be found on the summary page: SVG-FTG Summary.

Whereas the main theme of the preceding SVG-FTG V6.2 was integration with other software, the main theme for this version is special effects. This means that the topics will probably appeal to a wider audience.

In fact, most of the effects described below arise through the introduction of a single enhancement: the generation of a "ghost box" for each person-box. This is just another SVG entity but it can be customised to do these things below or things of your own choosing.

SVG doesn't have the concept of a programmable "z order" like HTML has, and so you cannot explicitly layer entities to control what overlaps what — the last thing drawn will overlap anything else at that position, and this is called the "painters algorithm". SVG-FTG is careful to draw the person-boxes, lines, images, buttons, etc. to ensure that, for example, lines do not overlap person-boxes. However, SVG-FTG V6.3 has implemented its own "z order" such that the new "ghost boxes" can be placed at the right overlap position. Detailed instructions for the effects illustrated here can be found at "Program Notes : Application Development : Header Files : Special Effects".

Three-D Boxes

The appearance of three-dimensional person-boxes can be quite an eye-catching effect. Although it looks like a simple side-plus-top shaded projection, the effect also puts a flare on the family-circles to make them look 3-D, and rounded ends on the lines so that they look more pipe-like when connecting the person-boxes,


The orientation of the projection, the shading, and the angle or length of the projection, can all be configured.

Drop Shadows

Drop shadows give the impression that each person-box is casting a shadow on a canvas, just a short distance behind the tree.


Picture Frames

Placing a picture frame over each person-box may sound a little over the top, but it can produce interesting border effects if you chose something nicer than this particular example.


Round Boxes

I thought about doing this years ago, but decided that it was too complicated. I was very happy when I found that it just fell out of this general-purpose special effect mechanism.



You can control the aspect ratio to change the circles into ovals, and even add the normal buttons onto such person-boxes.


Header Files

Long-time users of SVG-FTG will be aware that the header file templates employ a system of substitution variables in order to configure them according to your selected options. For instance ??title?? would deposit the title that you have assigned to the current tree.

That scheme has now been extended to include conditional compilation, expression support, and temporary variables. This feature was necessary in order to support the special new effects.

See "Program Notes : Application Development : Header Files".

Sundry

The 'Copy Descendants' option was accidentally omitted from V6.2 in the Viewpoint Manager. This very useful option was added to the Tree Designer and the GEDCOM Loader in order to make it easier to copy or transfer multiple families.

This has now been added to the Viewpoint Manager, thus making it easier to split very trees into usable viewpoints.