Silicon-based comedy

Heather Knight introduces Data, a robotic stand-up comedian that does much more than rattle off one-liners -- it gathers audience feedback (using software co-developed with Scott Satkin and Varun Ramakrishna at CMU) and tunes its act as the crowd responds. Is this thing on? Source: TED.

Today is my last day at AEtech

After 8 years of working with the most talented group of people I have ever met, I have decided to turn over a new leaf, working for a dynamic multinational delivering financial solutions Software in the UK. Today is my last day at AEtech.

I can’t say enough good things about the friends I have made and the talented people who have taught me so much. When I started here I never could have guessed that I would be creating cutting-edge software for the Industrial Automation sector. The experience working in multidisciplinary teams with very skilled Engineers is something to be a reminder of the very well done work.

Leaving AETech is different than any other job I have left. Joining AETech in 2003 was an easy decision and more strange was to have found success there. I felt like home, and even though it sounds strange, AETech is the first place I have worked where I feel I am part of the company instead of working for the company.

I am confident that this new step in my career will bring new outcomes. The time will tell. Meanwhile, I will go on blogging, telling you my bests and being in touch.

Many thanks to all of you who have filled with joy the past eight years. I am looking forward to what comes next and don't forget to follow me!.

-Jordi
London, UK ~ 2011

All Boot disk

Today one of my colleagues showed me this great site where you can download all the boot disk images from MSDOS 3.3 to Windows XP. Then you can use these images to start up a virtual machine. These ISO CD-ROM images have been created to allow you to boot your computer from a CD for the purpose of repairing various issues. The CD images are an exact copy of the boot diskette images. There is no advantage to using these ISO images over a diskette image. Some newer computers do not have a floppy drive installed, so these images allow for compatibility of newer machines.

Great job!.

Building my own Delphi Physics Engine part V

Today I felt inspired (after parts I, II, III and IV) and I tried to do a cloth simulation in the Thundax Physics Engine. There are a lot of things to do, but at least I can start simulating different components very fast without too much implementation. I saw one amazing implementation of the "processing cloth" in JRC313.com. Even though the applet is written in JavaScript, the performance is quite impressive and it's a nice work.

but, How it works?

"Every line in the cloth simulation is technically called a constraint and every point is a point mass (an object with no dimension, just location and mass). All the constraints do is control the distance between each point mass. If two points move too far apart, it will pull them closer. If two points are too close together, it will push them apart. The cloth is really then just a collection of constraints and point masses in a never ending struggle."

Andrew Hoyer.

using Relaxation in simple linear systems:

In the case of this cloth simulation all I needed to do was try satisfying the constraints as fast as I can. For things like simple rope simulations it may be necessary to satisfy several times (maybe 4 or 5). The more times you satisfy, the more rigid the constraint becomes. This process is known as relaxation and is amazing!. The displacement will then be of the form y(t) = Ae − t / Tcos(μt − δ). The constant T is called the relaxation time of the system and the constant μ is the quasi-frequency. (Wikipedia).

In the following videos you'll be able to check the performance of the simulated cloth. I took advantage of my previous bridge (spring + particles) and I've concatenated a series of bridges to set up a virtual cloth. Now the movement is quite astonishing:

In the second video I'm showing one of the new features for the next release: "the cutting tool". I still need to think about it, but for simple objects it could be simple to cut an object and see its reaction, like in the next video:

You can download the last version of the executable file here: thundax Balls demo v1.52. And maybe in a near future you'll be able to see something similar to the Puzzler for iPhone.

Other interesting video about physics and games is Crayon Physics from Petri Purho:

Crayon Physics Deluxe from Petri Purho on Vimeo.

I hope you enjoy the videos!

Related Links:

• JRC313 Processing cloth.
• Advanced Character Physics.
• Methods of Comparing square roots.
• Andrew Hoyer Experiments.
• Touching Cloth, Canvas Fu.
• Game developer magazine. 
• Farseer Physics. 
• Crayon Physics.

Building my own Delphi Physics Engine part IV

I'm still working on my solution, but I can advance you a preview of the smoothness of the application. I have improved the bridge particle and its interaction with external events. I'm working on a TStyle class that will enhance the GDIRender allowing the different particles to have a custom style on the screen and refactor all the classes to improve the scalability and interoperability of the Engine. If you are interested on testing the application, you can get the latest version of it from here: Thundax Ball Demo v1.1. In this version you will notice the improved interaction with the mouse and the circle particles. I have to work out a solution for the other particles, but I'm still designing the whole product and I need to test some of the features that I want to release in the next version. Once the version is ready, I will upload it on Sourceforge just in case you feel the urge to play with it!.

Here you can see the new performance:

Related Links:

• Building my own Delphi Physics Engine part I.
• Building my own Delphi Physics Engine part II.
• Building my own Delphi Physics Engine part III.