The set of scenes has some global parameters:

  <scenes>
    <timing>18.97s</timing>
    <startid_text>strt</startid_text>
    <begin_text>strt0</begin_text>
    <scene_origin>1</scene_origin>

Following def_perspective_scenes, the 2D transformed set of scenes are turned back to an SVG file with back_to_svg. The SVG file will have the defs removed and consist of the scene definitions as shown below.

The element start_id_text defines the text string, in this case 'w19strt7_' that precedes each id value. Scenes are numbered from 1 or the value of scene_origin if it is defined. This can be useful if the set of scenes has to be generated in separate runs. Paths within each scene are also numbered from 1.

<g id="scene1" title="constant">
<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>

<g id="scene2" title="constant">
<path id="w19strt7_2p1" class="w19sky01" d="M-1599.9,-414.1l3179.8,..."/>
<path id="w19strt7_2p2" class="w19sky05" d="M-837.7,-177.6c4.8,-0.7,45.4,6.9,49,7...."/>
<path id="w19strt7_2p3" class="w19sky06" d="M-372.2,-82.4c-24.2,26,-73.1,-13.8,-187.5,..."/>
</g>

Transforming the scene definitions with animate_scenes generates the animation sequence.