I hope this brief overview helps to understand and
extend the Luma sourcefiles.


Dependencies
------------

The SVG sourcefiles are created and rendered with

	Inkscape 0.92 <inkscape.org>

Individual files can be rendered in Inkscape with

	File > Export PNG Image (Full page at 96 dpi)

Unfortunately, Inkscape cannot export TGA images,
therefore it is necessary to convert the exported
images afterwards, for example with the GIMP or
ImageMagick (convert image.png image.tga).

The render.sh script automates this process.


Structure
---------

I recommend to open the SVG files in a text editor for
insight. Most images consist of simple path elements.
SVG filters are applied to these paths to add blurs
and glows. Shared filters and gradients are explained
and stored in dedicated files per directory

	common.filters
	common.gradients

The filters should not require editing. A detailed
explanation of SVG filter elements is available at

	<https://www.w3.org/TR/SVG/filters.html>

Filters may be turned off with

	View > Display mode > No Filters


Workflow
--------

I found it useful to create and edit unfiltered paths
in Inkscape, and then use a text editor to copy and
paste the path data (d="...") into an existing SVG file.
This minimizes the files and ensures that all images are
rendered identically. Element data can be inspected with

	Edit > XML Editor (or toolbar button)