At various places, concepts and drafts from the early stage of the
Lumiera Project are still reflected in the online documentation pages.
During the last months, development focussed on the Render Engine,
causing a shift in some parts of the design, and obsoleting other
parts altogether (notably we consider to use IO_URING for async IO)
- decision: the Monad-style iteration framework will be abandoned
- the job-planning will be recast in terms of the iter-tree-explorer
- job-planning and frame dispatch will be disentangled
- the Scheduler will deliberately offer a high-level interface
- on this high-level, Scheduler will support dependency management
- the low-level implementation of the Scheduler will be based on Activity verbs
The drawing code extracts style information from some "virtual"
widgets, which serve as logical placeholder for the actual nested
structure of tracks.
For sake of demonstration, I used rather obvious colours and
also all kinds of margin and padding; a screenshot was added
with annotations to indicate where some specific style settings
are utilised from the drawing code
- pick up all relevant values from CSS
- also control the width of the StaveBracket
- observe the given overall height
Moreover, complete documentation drawing in Inkscape
and add a page to the TiddlyWiki, describing the principles
underlying this design and construction.
Identify the elements of the construction geometry in the "Sketch"
object in the FreeCAD document and paste the corresponding coordinate
values into the SVG drawing prepared for documentation.
The arc segment parameters seemingly are given in radians;
and while FreeCAD uses the common mathematical right-handed orientation,
the orientation in SVG is applied clockwise rather.
...since the construction is determined now (and was worked out in FreeCAD),
the SVG will serve to document the construction; thus the drawing
primitives are rearranged to use the unscaled reference coordinates
to be extracted from the FreeCAD document; all scaling and placement
in the SVG document will be applied through common groups.
My idea was to use the brackets from musical notation as inspiration;
if you know some principles of typography, it is rather straight-forward
to come up with a pleasing design of such a bracket, using a
cascade of golden ratio relationships.
BUT ... all of this is geometry, and translating that into a symbolic
or numerical calculation is excessively complicated. Thus I looked
for ways to use some geometry or CAD software to build such a construction.
The geometry software I tired was woefully inadequate for this task.
Using the Constraint system in FreeCAD, building the construction went
smooth and straight forward, but then I was unable to export that drawing
in a way indicating the construction clearly.
So in the end, I'll have to hand-pick the resulting numerical coordinates
from the FreeCAD XML document and integrate them directly into Cairo
drawing code...
After sleeping some nights over it, rework the wording to make
my reasoning more clear and remove any possibly insulting undertone.
I have seen what I describe here, happening over and over again --
and several times I myself was the one cooking up "simplifications",
which caused lots of pain further down the road.
During the last years, I became more and more doubtful and regretted
that decision. In hindsight, the fundamental conflict was present
already in the original discussion.
My own experience showed me again and again: skipping the hard work
of specification for sake of some kind of fluid prototyping rarely
leads to anything solid. If "time to market" counts, this can be
a viable strategy though...
this is just an "interpretation" of the current architecture diagram,
created for inclusion into the developer report, indicating those components
to be augmented and integrated to get a simple render/playback to work
On my visit to Benny in the Black forest,
we decided to concentrate on a "Playback Vertical Slice"
and to announce that in the development report, using an
architecture diagram...
In 2017, I did a first design draft, followed by a design critique,
which partially obsoleted some ideas regarding command binding.
Mostly, the reason to abandon parts of that initial design was
due to the fact, that to many actual construction details of the
UI framework were not worked out at that time.
Thus I rather focussed on (re)-building a backbone for the timeline display,
in order to support that kind of flexibility aspired within the session model.
Now, when re-visiting the topic of an UI gesture (using simple dragging
of a clip in the timeline as an example for a first draft), I picked up
some of those planned structures, but tend to bind them together in
a slightly different way -- more akin to a state machine and less
in the way of an LR-parser.
This chagneset updates the relevant part within the TiddlyWiki
and the corresponding UML drawing to better reflect my actual thinking.
...in an attempt to clarify why numerous cross links are not generated.
In the end, this attempt was not very successful, yet I could find some breadcrumbs...
- file comments generally seem to have a problem with auto link generation;
only fully qualified names seem to work reliably
- cross links to entities within a namespace do not work,
if the corresponding namespace is not documented in Doxygen
- documentation for entities within anonymous namespaces
must be explicitly enabled. Of course this makes only sense
for detailed documentation (but we do generate detailed
documentation here, including implementation notes)
- and the notorious problem: each file needs a valid @file comment
- the hierarchy of Markdown headings must be consistent within each
documentation section. This entails also to individual documented
entities. Basically, there must be a level-one heading (prefix "#"),
otherwise all headings will just disappear...
- sometimes the doc/devel/doxygen-warnings.txt gives further clues
Even while EveryoneElese indulges in cool "flat" UI graphics,
we still think that a plausible 3D structure of UI widgets supports intuitive user interaction
As an asside, this commit fixes a mistake with the licenses of several of these documentation drawings.
I am the author of all these SVGs and thus can fix such a license glitch without much ado.
These drawing shall be licensed in accordance to the general rule for Lumiera Documentation,
which is to use a Libre-style license, here CC-by-sa (which does *not* limit commercial use)
- most notably the NOBUG logging flags have been renamed now
- but for the configuration, I'll stick to "GUI" for now,
since "Stage" would be bewildering for an occasional user
- in a similar vein, most documentation continues to refer to the GUI
Considering this since some time, since it more and more occurred to me
the existing conventional names are a misfit. And they are dull and clumsy.
This fall, I mentioned it to Benny, and he seemed to be rather favourable towards that idea,
which encourages me just to go ahead. Unfortunately, I am alone on the coding frontier
right now, which has several downsides, but at least it gives me the ability
to pull off radical moves.
This changeset fixes a huge pile of problems, as indicated in the
error log of the Doxygen run after merging all the recent Doxygen improvements
unfortunately, auto-linking does still not work at various places.
There is no clear indication what might be the problem.
Possibly the rather unstable Sqlite support in this Doxygen version
is the cause. Anyway, needs to be investigated further.
After some consideration, it became clear that this service implementation
is closely tied to the DispatcherLoop -- which will consequently be
responsible to run and expose this service implementation
