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Aliasing Beauty

victormartins — Thu, 30 Dec 2010 18:25:29 +0000

Finally, i posted about the Aliasing Beauty, a relative to Black&White project created for Written Images book. Read more..

CLNUI 4 Java (Kinect)

victormartins — Fri, 19 Nov 2010 02:14:44 +0000

Kinect is a new product from Microsoft for XBox360. With an RGB camera, a 3D depth sensor (structured IR light) and a multi-array microphone , it is able to compute a depth map, something very interesting for the interactive world of creativity and gaming. Nothing new as technology, but still, interesting and cheap. Since its release people have been trying to work in order to hack it and get it to work with windows and mac OS. Quite a few people have been working on drivers and a way to hack the gadget to get access to the color/depth data. One of these people is called Alex from Code Laboratories, the man behind the PS3eye camera drivers for PC’s. Recently, he released a new package (C and C#) that includes drivers and SDK for Kinect. I took the SDK and with JNA i wrote a library for java that wraps the original one and also tries to make its use easy for starters.

A very early release is available http://victamin.googlecode.com/files/CLNUI4J_01.zip. This might or might not work out-of-the-box and it sure needs improvement and more work, but as they say, release early, release often. This package includes the library and basic examples running on Eclipse IDE and processing IDE (untested). It is known that this library does not work directly with Processing.

EDIT! Version 0.2 is now available at: http://victamin.googlecode.com/files/CLNUI4J_02.zip.
You can now find a friendly wrapper and a couple of examples to get you started.

I would love to get some feedback, so if you’re a Kinect owner and you’re into java/processing, give it a spin and let me know how it works out for you.

Have fun.

GML Viscosity

victormartins — Tue, 07 Sep 2010 07:32:25 +0000

So here it is, the application and source code for GML Viscosity.

I finally took the time to clean up this project and make a public release. In the packages you will find binaries and source code for the application, so if you’re thinking of using it and come up with something nice, let me know. After the first release i have fixed some problems with memory access and crashes. I have also added a simple UI for easy pick of tags from the “data/tags” folder on your hard-drive.

What is it?
- GML Viscosity is an experiment. It is application used to draw GML tags on a viscous liquid rendered purely on the GPU side.

What does it do?
- It liquifies your tags, in a way you can hardly read them but still looks cool (thats graffiti).
- It is possible to load gml files from the disk or directly from the “lots of zeros”book database.

How can I interact?
- Not implemented on this version. This version selects and draw gml files randomly from the web or from a tags folder. For a smart person it should be easy to add mouse support. The code is also prepared to support multitouch so, it should be easy to implement TUIO and create your multitouch version.
- Use ‘r’ key to randomly fetch a new tag from the website and if available it will draw it on the screen.
- Use the GUI window to pick any tag from the folder “tags” inside data folder.

Where can i get it?
Windows Version | MacOSX Version

Have fun.

MSAOpenCL for Java and Processing

victormartins — Thu, 29 Jul 2010 01:57:33 +0000

Recently I have been doing some work with OpenCL and i found myself messing up with old code and re-writing most of it . At first it was interesting and quite funny but no more, so, I thought it was time to make things easier for myself and just make things reusable by creating a wrapper which would wrap most of the boring and time-consuming parts. This would be a wrapper on OpenCL for Java and/or Processing. Well, a well known guy named Mehmet “Memo” Akten has done such a wrapper in C++ for the OpenFrameworks and Cinder libraries. I have ported it to Java.

There are some problems with reading/writing from/to GL textures. For some reason it crashes on me. I have been working with JavaCL‘s author, so hopefully it will be working soon.

:: Download

Download it, install it and try it.
If you find any problems or if you have suggestions, let me know.

Have fun.

Mass cube rendering

victormartins — Sat, 03 Apr 2010 12:02:01 +0000

I have recently done some experimental work in order to render mass amounts of cubes. I was moved by this video from Smash, i wanted to know how far i would be able to go on my NVidia GT240M (rendering side). My first choice was Geometry Shaders.
I quickly wrote an app that sent a list of points in space to the GPU and a geometry shader would generate a cube mesh for each one of the points. Tested it on 100.000 cubes and the framerate was bad(10fps or so). The time was now for optimization.

Next step was to optimize the cube generation by lowering from a 24 vertex cube to 14 vertex triangle strip. Things got better, but nothing close to my expectations. I was not satisfied, i mean, i had alot of cubes on screen (100K which was not that much) and that was it, nothing else. We’re talking about 20fps or so, for 100.000 cubes (around 1.2 million triangles per frame). Later on i added vertex normals to the geometry shader and started to work on some lighting/shadowing, but i ended up going back on the rendering side of the job. Meanwhile, i was speaking with a friend of mine about this idea and we were discussing ways to compute lighting but i couldn’t stop thinking about my real problem. So it came to me.

Previously, i have done some experiments with opengl hardware instancing, but never got to do much about it . What better time than now, so i grabbed the project and took it for a spin. After a few hours i had the same amount of cubes on screen with a much much better framerate. Quickly implemented some eye-candy (coloring, texturing, vertex lighting), some tweaking here and there and as i was listening to Mr. Peter Broderick (hi, i love you man) added some audio analysis to the feature list.
Last but not least, a kind of “Brownian Motion” was used to generate points in space, increased the cube count to 512*512 and watched it flow ( at 20fps ).

In conclusion, Hardware instancing was much easier to implement and performance seems much better at first sight. Above is a video of 262.144 audio-reactive cubes with GPU animation and basic lighting at around 20fps. For my video card i think that is very good. On a sidenote, i have not given up on the geometry shaders. I am not sure what will be my next step regarding the subject (back to geometry shaders?) but for now this is it. Hardware Instancing kicked Geometry Shaders in the ass.

Monologue Muet – Outside projection

victormartins — Sun, 07 Mar 2010 20:18:22 +0000

This is the outside projection for Monologue Muet exhibition, a photography work by Sue Elie Andrade De.
Based on her video called The Rain, i have created the outside projection with response to physical properties, like doors and windows.

JavaCL, the new OpenCL4Java

victormartins — Wed, 17 Feb 2010 07:11:21 +0000

I have noticed that OpenCL4Java is on version 1.4beta by now and that my examples were crashing when running on a GPU device. Today i took the time to do something about it. I have downloaded the new version and have updated the examples to run with 1.4beta. Everything seems to work just fine now, if you have a different opinion, please do let me know.

Download: http://victamin.googlecode.com/files/JavaCL_1_4b.zip

Have fun!

(hmm) Greebles

victormartins — Wed, 04 Nov 2009 11:37:08 +0000

Since Star Wars(tm) (so i’ve read), texture-based techniques have been used to improve the detail on planar and easily curved surfaces. The one i’m talking about here is called Greebles. Apply an heightmap texture on a surface and on a per-pixel basis, geometry is generated acoording to the pixel’s intensity. By doing it you get more detailed surfaces without having to model every little part by yourself, making things more interesting, realistic and much more appealing.

To achieve this i’ve picked Vertex Texture Fetch. It allows you to access texture data on the vertex shader. Pass a texture to the vertex shader and offset the surface vertices by the pixel’s intensity. To improve the looks, bump-mapping with multiple lights have been used. Everything presented here is generated on the GPU, even the objects. Runs nicely on a Nvidia 8200M. Lots of space for improvement.

OpenCL 4 Java & Processing

victormartins — Fri, 30 Oct 2009 18:09:42 +0000

I finally took the time to play with OpenCL. I was motivated by the particle example from Rui Madeira. After speaking with him, he gave me a few other links on more examples like Memo Akten‘s 1.000.000 particles running with mouse interaction on the GPU, the very NVidia’s first OpenCL application example, etc. I was intriged! So i took the day to play with OpenCL4Java and ported Rui’s example to Java running on Processing’s IDE. I’ve tested it with a Intel Quad core and i found the Rui’s sample to crash with GTX280 videocard. I didn’t gave it much thought but it might be for that for-loop in the program on the particle-particle iteration. In the other hand, Memo’s example ran easily on the gpu side. I should have made an example of mine, but it was easier to just port their examples and get things running. That was the main goal.

I have only tested this under Windows XP 64bit with ATI Stream SDK and Nvidia drivers. If you find any problem, please report.
One other thing: Memo’s example isn’t the real thing. It’s simply the CL program. So you won’t be able to get all the fuzzy million particles around. Not yet.

Library/Examples available here: http://victamin.googlecode.com/files/OpenCL4Java_1b.zip

Installation steps:
1. Copy the library to processing’s libraries folder
2. Install ATI Stream SDK (i have packed the OpenCL.dll file, still you might have to install the whole pack). If you’re using Nvidia, install the OpenCL drivers and toolkit
3. Open the example and run it.

Enjoy and have fun!

MovieGL – Rendering movies with JOGL in Java/Processing

victormartins — Wed, 28 Oct 2009 21:17:57 +0000

I have tested most of the libraries available for processing able to render video files, but i never was happy. Either it became slow, unstable or just crashing. I wanted something better, so i went looking into JMF (Java Media Framework).

During my research i came across this Pirelenito’s website with a great example on using FOBS+JMF, exactly what i needed. So i downloaded it and started working on it, putting into it a bit of myself.

So here it is, a first pre-beta version of a library capable of rendering movie files (with sound) with Java/Processing without much effort.

NOTE! I’m still having problems with a couple of codecs like DivX, Xvid, H264. It crashes on me when rendering some of these, but it works just fine for Mpeg4, PhotoJPEG, Cinepak. It isn’t perfect, but if you be careful and use the right format/codec it will go smooth. Meanwhile i will be working on a better version.

Website: www.pixelnerve.com/processing/libraries/moviegl
Library Package(s) at: : http://code.google.com/p/victamin/downloads/list

Have fun!

Credits goto Pirelenito. Thanks for sharing.