[Bf-animsys] Depsgraph refactor progress

Fri Jan 30 05:26:43 CET 2015

I guess I should respond/comment about a few of the points raised here:

Regarding Daniel's points:
I tested his file earlier, and the animation seemed to be working (at least
on the main rig). The only errors I did run across there were that it was
trying to add animation links whenever it encountered animdata, even if
there were only drivers present.

(EDIT: After retesting again while writing this reply, I discovered that
the animation will be broken here if the transitive reduction is removed.
Specifically, the bones will animate, but the geometry won't deform)

Regarding JP's points:
Aarrrggghhh!!!!

Chasing down the bugs in that file has been so tricky!   (NOTE: Removal of
transitive reduction again breaks that rig here). Which transform
constraints exactly are the offending ones we should be removing?

Other notes for testers:
- Rigidbody support "should" be working with the new depsgraph. 1-2 weeks
ago I went through ensuring that all the necessary links are at least
getting created for that, but I'm not sure if any of the rigidbody
constraints stuff or integration with other constraints/parenting using the
results or influencing the sim are totally working yet.

- As Sergey mentioned though, the rest of the physics integration
(specifically anything particles related) is really hit and miss. It really
hasn't been hooked up, so, apart from some things working (via the
placeholder uberevals), it shouldn't be doing anything.  Prime example of
this is that the background specs/floating stuff in the Caterpillar file
from the Gooseberry teaser don't work  by and large.

- Regarding the graph visualisation output stuff we try to use for
debugging, here are a few words of hard-earned wisdom to save some pain:
1) For "Graphviz" Exports (.dot), only use "dot" on very very simple
graphs. This way of showing the graphs will give you the clearest idea of
what's going on, but it will crash or output gibblish on cue if given
something even slightly more detailed

2) Again for "Graphviz" Exports: If "dot" fails, use "neato" instead. But
be warned that neato doesn't always produce graphs which make much sense
(heaps of overlaps), and could well take 20-30 minutes for some rigs at
least.

3) The experimental OGDF/GML export doesn't currently have a working layout
engine attached, but it does output basic node + relationship info.

4) For difficult to visualise graphs, it is possible to import the .dot or
.gml files into "Tulip" to visualise them with various different algorithms
until one of them manages to wrangle it into shape. Be warned though that
it doesn't show directed arrows, and it also lacks most of the context
information, so it may still be difficult figuring out what's going on.

On Fri, Jan 30, 2015 at 2:15 PM, Juan Pablo Bouza <jpbouza at hotmail.com>
wrote:

> Oh poor sergey! Man you should have asked me about Koro so I could help
> you debugging.
>
> Yep, that rig has 1 dependency cycle in each of its legs (the
> transformation constraint), and I think that it also has one in his head,
> haha. But well, somehow it worked ok cause those cycles were never actively
> in use, as some drivers turned on and off some constraints which avoided
> the cycle, functionally. So I guess that that is why the rig just worked
> and those cycles never popped up when we were animating the rig.
>
> By the way, the cycles were not intentional... you know, I did the
> freaking rig in like 2 days, hehe.
>
> So, now I've also tested Victor, which basically has the same basis as
> Koro, and as you say, it works perfectly well. So you've done a great job!
> I would say that you have nothing else to solve regarding these testing
> rigs, as the problem with koro was a rigging fault.
>
> I did test playback speed and these are my results with Victor:
>
> *Armature only playback: *60 fps vs 36 fps (refactor branch)
>
> *High resolution character playback:* 35 fps vs 20 fps (refactor branch)
>
> *Proxy character playback: *49 fps vs 24 fps (refactor branch)
>
> I did the benchmark inserting keys in several controllers.
>
> The good thing is that I also tested driving some "distance" value of a
> limit distance constraint, with the scale of a bone and it worked like a
> charm!
>
> Keep up the good work guys!
>
>
>
>
>
> ------------------------------
> From: zanqdo at gmail.com
> Date: Thu, 29 Jan 2015 16:00:59 -0600
> To: bf-animsys at blender.org
> Subject: Re: [Bf-animsys] Depsgraph refactor progress
>
>
> I've tested on my current Tara rig and it works perfectly! Congratulations
> to all involved! The only thing failing is the actual playback of the
> animation. Can't say anything about speed yet because of that :)
>
> Daniel Salazar
> patazstudio.com
>
> On Thu, Jan 29, 2015 at 9:09 AM, Sergey Sharybin <sergey.vfx at gmail.com>
> wrote:
>
> Hi,
>
> Just a quick update on the happenings in depsgraph_refactor branch.
>
> = Status overview =
>
> So far we've been focusing on having interleaved drivers and armature
> bones updates and didn't pay much attention to other aspects. So:
>
> - Meshes/curves/metaballs are ported to the new dependency graph
> practically without visible changes. There are some underlying changes
> which would allow moving blender to fully node-based system, but those
> parts are basically NO-OPs currently.
>
> -  Armatures takes really long time to deal with. Basically the status is:
> simple rig works, complex ones needs more investigation and some design
> decision we need to do (read about that later). Armatures supports
> interleaved updates, which means it is possible to have drivers/constraints
> between different armatures and have proper updates without lags.
>
> - Dupligroups nad proxies are not currently supported. They basically
> needs to be re-implemented in the new system. I'm currently looking into
> this.
>
> - Rigidbodies, simulations and so might work by co-incident, but they'll
> need to be revisited, because there was some code from Lukas in there but
> depsgraph changed a lot since then and things might not be working as
> expected now.
>
> - Animation/drivers are expected to work, supporting more interleaved
> behavior (this mainly applies to drivers, animation does not have
> dependencies).
>
> - Layer visibility (when object appears visible on the layers) shouldn't
> have lag now. I'm not totally happy with the current implementation of this
> in the branch tbh, but it's simple to make it nice and clean using Brecht's
> idea of changing a bit logic around LIB_RECALC flag.
>
> - Depsgraph building is now quite slower, but we didn't invest time into
> optimizing it. Evaluation might also be a bit slower because of more
> granular operations which increases overhead of task system. This will be
> reviewed after all the features are working in depsgraph.
>
> - Cycle detection and solving needs to be implemented for the new system.
> Was looking into it this week, but didn't quite finish yet.
>
> Think this mainly covers the state of the branch. Now, why it's not moving
> much faster you might wonder. That's basically because issues with rigs are
> really tricky to investigate (trying to find out what exactly is wrong in
> rig with 1K bones...),
>
> = Testing =
>
> While it is known that complex rigs might fail (for example, Koro rig
> doesn't fully work) other rigs are just rock-solid now (Victor from
> gooseberry, agent from the agent short movie) it would help if someone will
> test more right and if they fails minimize them as much as possible (to few
> bones only, so it is clear what's going on). Such a minimization process
> took really log time from us, so having small correct rigs which doesn't
> work would really help. Correct in terms there's no unsolvable cyclic
> dependency i.e.
>
> = Constraint targets =
>
> For until recently we tried to make it so constraint targets are using
> final bone transformation (after parenting + constraints + solver) which
> what we understand from initial riggers feedback what's needed. However,
> some existing rigs seems to be using some constraint expecting them to do
> opposite -- use pre-solver bone transformation.
>
> Basically that's the exact stopper for armatures atm -- understanding what
> transform riggers actually want to work with.
>
> So, let's start this question again: when you're using bone as a
> constraint target, which transform you expect to be used?
>
> --
> With best regards, Sergey Sharybin
>
> _______________________________________________
> Bf-animsys mailing list
> Bf-animsys at blender.org
> http://lists.blender.org/mailman/listinfo/bf-animsys
>
>
>
> _______________________________________________ Bf-animsys mailing list
> Bf-animsys at blender.org
> http://lists.blender.org/mailman/listinfo/bf-animsys
>
> _______________________________________________
> Bf-animsys mailing list
> Bf-animsys at blender.org
> http://lists.blender.org/mailman/listinfo/bf-animsys
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.blender.org/pipermail/bf-animsys/attachments/20150130/13231a8c/attachment.html>