http://th30z.netsons.org Matteo Bertozzi, Objective-C, Cocoa, C, C++, Qt4, iPhone, Mac OS X, Open Moko, Matteo Bertozzi Development Tue, 10 Nov 2009 08:39:44 +0000 http://backend.userland.com/rss092 en Again, another week spent on OpenGL. I don't know why but I cannot stop to experiment with Meshes, Vertexes, Faces and Textures. It's too amusing! But Todays, post it's just an update of GLData, the small gl data library that I use for my experiments. The new features, for this update are: ... http://th30z.netsons.org/2009/11/opengl-walk-around-camera/ Still experimenting with OpenGL, I've played just few games in my life Formula 1 and Tomb Raider. The second one, is more interesting to "reproduce" to learn something of OpenGL, meshes and how all of this world works. Following the latest posts, I've added the PNG support to the GLData ... http://th30z.netsons.org/2009/10/opengl-meshes-and-png-textures/ As you can see from the bigger Screenshot below, Today is time to put some characters on the OpenGL stage. And the two guys below are two of the characters of Yo Frankie! (http://www.yofrankie.org/). Following the preview post I've extended my GLData Library adding support for Textures and using another ... http://th30z.netsons.org/2009/10/opengl-meets-blender-meshes-and-textures/ During my work, I've found an interesting library GNU Triangulated Surface Library (http://gts.sourceforge.net/) that does, some nice things, like Constrained Delaunay triangulations. But what I was really searching today are just meshes to use in my OpenGL experiments. And there're a some GTS samples available on the GTS website. The screenshot ... http://th30z.netsons.org/2009/10/opengl-gts-format-lights-and-cameras/ Last night I had a terrible nightmare, where all the apple/mac bloggers says "This app cannot be use used with older macs because it uses OpenCL, so you need the newest NVidia…" ..Fortunately, was just a nightmare. Everyone can use OpenCL, old macs (as my macbook) cannot use GPU, and cannot ... http://th30z.netsons.org/2009/10/opencl-is-for-everyone/ For many of you, this sounds like a stupid thing. But for those that just use gcc -I from command line, can be a pain find how to do it. So, the problem is. How can I specify my Include path in XCode (gcc -I./mypath). Tap on your project target, and click ... http://th30z.netsons.org/2009/09/tip-xcode-header-search-path/ Last week on LWN Valerie Aurora as posted a great article (as always) POSIX v. reality: A position on O_PONIES. http://lwn.net/Articles/351422/. fsync() is often more expensive than it absolutely needs to be. The easiest way to implement it is to force out every outstanding write to the file system, regardless ... http://th30z.netsons.org/2009/09/file-system-delayed-allocation-fsync-solution/ In the last years I've always used a "parallel task" approach foreach loops that I've in the code, not always to speedup but even to clean-up the code. How to do it? Wrapping threads and Thread Pool like in this C# Parallel Forech Code. Snow Leopard has introduced a new BSD-level ... http://th30z.netsons.org/2009/09/grand-central-dispatch-first-look/ While I'm thinking and waiting for suggestions on how to improve my file-system block cache algorithm, I've decided to apply some changes to the Raleigh File-System Format (source code is not published yet). Following the ideas of Valerie Aurora of Repair-driven File System Design, I've decided to add for each block ... http://th30z.netsons.org/2009/09/file-system-and-data-block-back-reference/ It's finally here.  Mac OS X Snow Leopard, The world's most advanced operating system. Finely tuned. Ok, It's one week later... but I've installed it just right now. Maybe tomorrow morning an usage example of Grand Central Dispatch. http://th30z.netsons.org/2009/09/mac-os-x-10-6-snow-leopard/ Yesterday I've played a bit with AVAudioRecorder, and this is a very small and funny example. The main Idea is to create something like a wind mill that works with voice instead of wind. The code below shows you how to record something. Then with the updateMeters() and peakPowerForChannel() you can extract ... http://th30z.netsons.org/2009/08/iphone-voice-mill/ I need to replace my old filesystem cache algorithm with something more new and efficient. The old one is based on LRU/LFU algorithm. There's a queue of cached blocks and an Hashtable to speedup block lookup. struct blkcache_buf { struct blkcache_buf * next; /* ... http://th30z.netsons.org/2009/08/block-cache-algorithm/ I Love use Binary formats, instead of XML, and JSON. Here is my Generic Binary Format for data transmissions or serializations. Data is composed by three blocks. The first one 1byte that describe all information about the object, like "is a single Int object" or "is a list", then tells ... http://th30z.netsons.org/2009/08/tip-generic-binary-format/ I'm back to code on my "Cloud" FileSystem, and distributed tools. And here is a little tip. When you're working on Data, probably you store it as a Key-Value Pair on a BTree or something similar, and maybe this key is an aggregation of information... Maybe you've one bit of flag, ... http://th30z.netsons.org/2009/08/tip-generic-key-comparer/ Every programmer loves to reinvent the wheel, and reinventing the wheel is still my primary hobby. Sometimes you need to reimplement a Network protocol to use with your favorite language/library, sometimes is only for fun, but if you're in the Business World maybe is "better" (faster) to use one of ... http://th30z.netsons.org/2009/08/unified-notification-service-avoid-the-wheel-reinvention/