8. Animate Scenes

The transformation animate_scenes uses the elements at the head of the file:

  <scenes>
    <timing>7s</timing>
    <startid_text>strt</startid_text>
    <begin_text>w19strt6</begin_text>
    <scene_origin>1</scene_origin>

Transforming the scene definitions with animate_scenes generates the animation sequence.

It is quite a simple transformation. The first scene is retained and a set of animate elements are generated where the values attribute consists of the corresponding path d attributes separated by semicolons.

The output looks like:

<g id="scenes">
<g id="scene1">
<path id="w19strt7_1p1" class="w19sky01" d="M-1589.9,-424.1l3179.8,..."/>
<path id="w19strt7_1p2" class="w19sky05" d="M-837.7,-177.6c4.8,-0.7,45...."/>
<path id="w19strt7_1p3" class="w19sky06" d="M-372.2,-82.4c-24.2,26,-73.1,..."/>
</g>

<animate attributeName="d"
values="M-1589.9,-424.1l3179.8,... ; M-1599.9,-414.1l3179.8,... etc"
fill="freeze"
begin="w19strt6.end"
dur="7s"
xlink:href="#w19strt7_1p1"/>

The timing element defines the dur attribute of the animate element. The begin_text element defines the begin attribute value.

By careful use of the parameters it is possible to run a sequence of animations one after the other by just concatenating the individual files together. Typically a logo animation is around 10 separate scenes each with up to 24 keyframes.