Bullet Rigidbody Integration in Trunk

Nearly a year to the day when I released a cleaned up (and updated) codebase for the Bullet Rigidbody Integration from my GSoC 2010 work, it's finally now in trunk (commits 54019 - 54026) !

Cheers to Sergej for finishing this off as part of his GSoC 2012 project. Enjoy!

Google Summer of Code 2012 -- Projects Wishlist

Over the past few weeks there has been quite a lot of discussion about projects which would be cool to have for this year's Google Summer of Code. With applications opening again this week, I'll take some time to quickly go over a few of the project ideas that have been coming up.

Bullet SoC - Doing the SVN Dance - Part 1

In order to start work on this project again, especially on Point Cache support, I figured it was time to grab a more up-to-date Blender trunk to work from, since many things have changed there AFAIK, not to mention in a few other places too.

User Contributed Bullet Demos...

It's great to see people going out and playing with my SoC work. Keep them coming! :)

Aligorith Blender Branch - Bullet Integration from Everton Schneider on Vimeo.

In 2 weeks time, I should start to have time to get back to work on this at last. But first, it's back to work on the upcoming end of year exams...

News roundup...

This is a bit of a mixed-bag post; there have been things happening around the place to ramble about.

1) My first attempt at food photography (this photo is quite literally the first shot of food I've ever taken, with some PP to make it look even tastier):

I guess you could call these potato fritters or so. It's potato, spring onion, egg, and salt. I like salt.

2) Yesterday afternoon, there was suddenly a knock at the door... it was the FedEx delivery man!

Thanks Google! My SoC T-Shirt and Certificate arrived at last :)

3) Last but not least...

At long last, "Sintel" has now been released online :D

If you haven't seen it already, what are you waiting for? If you have, why not watch it again ;)

Bullet SoC - Still researching the "brick wall" scenario + Potential Solutions

It's been a while since I've made an update on this project, so it's probably time that I did so. Last time I did, I was still investigating the making sure that "brick walls" could be simulated easily using the Rigid Body tools I'd put in place (including changes/improvements to the brick wall template).

Perhaps seeing so many crumbling chimneys, and fallen-away walls around the place in recent weeks has further highlighted the importance of being able to simulate this. And perhaps, indirectly, suggests a solution :)

Bullet SoC - Experiments, Fixes, and More to Come...

So, the official GSoC 2010 period is over now, but that does not mean all coding activity on this project is stopped for good.

Leading on from where I left off last time, I've been conducting some experiments and tweaks with the "Wall" template, implementing some ideas for this that I didn't have time yet to do and investigating how to improve the stability of this asset in actual sims.

Bullet SoC - Last minute goodie

Putting the "Construction Toolkit" back into "Bullet Construction Toolkit", I present:

Rigid Body Templates

 Templates can be accessed from the 'Add' menu (Shift-A)

Ultimately, the intention behind these is to allow you to quickly add a set commonly-used of Rigid Body setup to your scene. That is, setting up such a setup would otherwise be quite tedious, as you'd need to create several objects, or similar.

Bullet SoC - It's not over yet...

The official SoC period is quickly drawing to a close, coinciding with the weekend before a raft of assignments are due. The weather over the past two days has been equally dreary (as assignment death marches go)...

Wintry Weather

Unfortunately, this has meant that I haven't had time to make a few last minute tweaks I'd have liked to do "within" the official timeframe. However, rest assured that I'll be working on those again under a hopefully clearer frame of mind in a week's time.

So, as the saying goes, it's not over until the fat lady sings. Or in this case, the code is in trunk and suitable for widespread consumption. :)

Bullet SoC - Squashing those bugz

I've just been doing a bit of a bug-squash sprint tonight, dealing to a few reported issues which have lingered in this branch for a while. If you've been finding any bugz in particular, please test with a recent version, before reporting on here.

Bullet SoC - Winds of Charge

After a bit of a development hiatus due to some unforeseen troubles in trying to get the Manipulator API up and functioning (as of time of writing this, they still haven't been resolved), it's time for some new cool stuff and updates here again. So while I'd have liked to get the Manipulator API finished during/as part of this year's SoC, it looks like it wasn't meant to be...

How time flies...

Wow... another week has passed... and it's now the end of July! That means the daffodil's will soon be coming out, if snow or frost don't get to them first.

The first time I noticed was on Wednesday (or was it Tuesday), when for whatever reason, I thought it was still the 18th (it was the 21st)! Eek... then again, I never professed to being too good with remembering numbers (har har har)

SIGGRAPH 2010 also should be starting today, but it seemed that it was always 3-4 weeks away still... I mention this, as I remember Erwin from Bullet/Sony-Imageworks(?) saying that he'd be interested in doing of demo of the Blender-Bullet integration during his Bullet/Collision course. It's a pity that once again I couldn't make it yet (if only semester 2 started 3-4 weeks later ;)

In other news, this Manipulator API is starting to take a bit too long to finish! Grrr... but hopefully it'll be ready soon.

Bullet SoC - A Guide to choosing Collision Shapes

As promised in my commit log for Triangle-Mesh Collision Shapes, here is a brief guide (with demonstrative videos) on choosing collision shapes when working with Rigid Body simulations.

A few bugs showed up (and most but not all were fixed) during the course of the video recording process, so the initial commit of this functionality may not be sufficient to reproduce these videos.

Doh! Glimpses of enlightenment...

Don't you hate it when you work on the wrong file and keep wondering why something didn't work?
While doing another round of bug-squashing on 2.5 this evening, I was trying to debug a crash but every attempt at debugging the problem didn't improve the situation. Even the most trivial and blatant of test checks was failing! Just when I was about to call it a day, and go back to my SoC work, the glaringly obvious cause stood out: I had been editing the file from my SoC branch not the 2.5 tree. (Idiot moments += 1)

[Edit: It looks like the Durian team were also inspired to post about some of their moments... heheeehe]

Moving on to something a bit more relevant to SoC/Bullet stuff now...

Bullet SoC - Rome wasn't built in a day...

... and neither was the Manipulator API or some of the other targets I've been working on going to be easily solvable within the space of a week.

A few quick rounds of status updates:

• After discussions with Theeth, we now have version 2 of the Manipulator API design.
• Coding of this has been in progress over the weekend, though this is taking a bit longer as...
• A new term at Uni starts again today :(
• Bullet Constraints work is going "back to the drawing board". There are some issues I need to think over again here (not to mention running into some really shabby stuff along the way)
• Dupli-instances... grrr... if only there were an elegant way to handle these...

Hopefully there'll be some more interesting updates to come later this week... (fingers crossed)

Bullet SoC - Monkey Business

Just a quick video update (only one this time):
http://vimeo.com/13143533

Mesh collision shapes can now be used. While it's still more efficient to use the basic primitives instead for most cases, these certainly do come in handy.

I'm currently pondering whether this should be the default mode to give more immediacy for most cases, at the expense of users needing to work harder to fine tune their results. This way, we could give some of the other 'auto' modes in other software a bit of a run for their money (literally) ;)  Comments?

Bullet SoC - Manipulators API Design...

I've been planning this for a few months now on and off, and even decided to try to fit this in as part of Bullet SoC work. I figured it would work quite well in furthering our goals of creating a Bullet Construction Toolkit, since visual tools are potentially more natural to use in the long run.

So, without further ado:
Presenting the Manipulators API Design Doc

Barring a need for significant re-architecturing, I'll start trying to implement this tomorrow, and hopefully there'll be some cool stuff to look at soon afterwards.

Bullet SoC - Heads 're rolling [Updated]

After a few days' work, I think it's now time for another round of video updates :) Artifact 4 - Animated properties and simulation controls http://vimeo.com/13029755 Artifact 5 - Rolly-Polly: Collision shapes http://vimeo.com/13031113 Artifact 6 - Pong! Recording animation live from the viewport (using realtime transform recording feature), and seeing live/realtime physics feedback including collisions while recording. Update (July 3rd, 5:30pm): new video now available after some bugz were squashed this morning http://vimeo.com/13051630 In response to some viewer comments, I've slowed down the videos a bit (both times recorded at 10fps; last time video apparently used 10fps, but this time I've set that to 5fps). I've also had to make some changes to my video-making pipeline to make the files more manageable. There'll be a post with the specifics of this process tomorrow.

Bullet SoC - Stay tuned...

Just a quick note that I am preparing another nice set of updates on the current status of the tools. I've got a few (hopefully interesting and tasty) demo videos planned for then which I was going to record today. However, while rehearsing these, I found a few bugs which will set things back another day...

Bullet SoC - From the trenches

I've spent most of yesterday trying to track down some of the various problems afflicting the simulation system to little avail (as mentioned in an earlier post).

What is becoming apparent is that navigating (and trying to understand) Bullet's API is becoming quite an exercise in itself at times. Through this process, I'm really starting to appreciate the extent that C++ can be used to obfuscate the meaning of or the ability to easily find code to understand it. Furthermore, I still don't think that doxygen/javadoc-like tools are totally up to the task of improving this situation a lot of the time, but serve to introduce their own layers of complexity into the situation (* details to come in a future post when I get around to it).