Back in February at the Hacker Hotel camp in the Netherlands, among the many pieces of work around the venue was a rather attractive LED cube. Very pretty, but LED cubes have been done many times before.
If a casual attendee had taken the time to ask though, they might have found something a little more interesting, for while the cube in question might have had the same hardware as the others it certainy didn’t have the same software. [Polyfloyd] had equipped his LED cube with OpenGL shaders to map arbitrary images to the cube’s pixels in 3D space.
Hardware-wise it’s the same collection of AliExpress LED panels and Raspberry Pi driver board that the other cubes use, in this case mounted on a custom laser-cut frame. Driver software comes from an open-source library round which he’s put a wrapper allowing input through a UNIX pipe. This can take the RGB output of an OpenGL shader, of which he has created both 2D to 3D and spherical projection versions. The must-see demo is a global map of light pollution, and the result is a rather impressive piece of work.
If LED cubes are your thing, don’t forget this recent Hackaday Prize entry.
Perhaps we’ve been concentrating too much on the hardware side of the Raspberry Pi. Sure, connecting the Raspi to the outside world through GPIO pins is cool, but let’s not forget we’re dealing with a full-fledged Linux box here. [chris] is doing his best to keep us in check with by bringing the power of OpenGL graphics to the Raspberry Pi.
Previously, OpenGL ES was only available for xorg but [chris] successfully added support for Raspbian. There’s a great physics demo [chris] put together showing off 128 spheres and cubes bouncing around a plane.
Right now, [chris] is looking for people to contribute samples and tutorials for making accelerated 3D graphics on the Raspi. You can grab all the code over at [chris]’ Git and contact him over on the Raspberry Pi forums if you’d like to help out.
As with any graphics demo, check out the videos after the break.
Continue reading “OpenGL On The Raspi”
If you ever need to manipulate images really fast, or just want to make some pretty fractals, [Reuben] has just what you need. He developed a neat command line tool to send code to a graphics card and generate images using pixel shaders. Opposed to making these images with a CPU, a GPU processes every pixel in parallel, making image processing much faster.
All the GPU coding is done by writing a bit of code in GLSL. [Reuben]’s command line utility takes that code, sends it to the graphics card, and returns the image calculated by the GPU. It’s very simple for to make pretty Mandebrolt set images and sine wave interference this way, but [Reuben]’s project can do much more than that. By sending an image to the GPU and performing a few operations, [Reuben] can do very fast edge detection and other algorithmic processing on pre-existing images.
So far, [Reuben] has tested his software with a few NVIDIA graphics cards under Windows and Linux, although it should work with any graphics card with pixel shaders.
Although [Reuben] is sending code to his GPU, it’s not quite on the level of the NVIDIA CUDA parallel computing platform; [Reuben] is only working with images. Cleverly written software could get around that, though. Still, even if [Reuben]’s project is only used for image processing, it’s still much faster than any CPU-bound method.
You can grab a copy of [Reuben]’s work over on GitHub.
For everyone using a later version of Windows like Vista or Windows 7 they will probably never get to enjoy the awesomeness that was Wing Commander…until now. [Jari Komppa] has managed to use DirectDraw to his advantage and hack out a solution to this disappointing problem. He used DirectX to do this and has even managed to get OpenGL to load from a DLL after a few problems with Windows XP and Windows 7. This is truly a step forward in retro gaming. No more should we have to load a virtual machine to play Starcraft. Hopefully getting this ported to even older games such as Sim Farm or Commander Keen are on the way!
[Losinggeneration] managed to get a homebrew OpenGL application working on the Didj. It’s nice to see the community driven work advance on this device but something else also caught our attention from the forum post. Another poster pointed out that [losinggeneration] has files in one of his directories called “glquake-didj” and “glquake-didj.dbg”. We hope that means a working version of Quake is on the way for the hackable handheld.
[Thanks JJ Dasher]
[Andrew Magill] just added his Orientation Aware Camera to the Hack a Day Flickr Pool. It uses a 3-axis magnetometer and 3-axis accelerometer. He didn’t want to spend too much effort on the USB side so he picked up USBMicro’s U421. It’s a fairly well documented preprogrammed microcontroller for USB. He later regretted this; his final sample rate was only 5Hz because of all the overhead. Using the positional data the, webcam image can be corrected for any sort of shaking. [Andrew] took this one step further by using OpenGL and stitching all of the video frames together live into a full panorama. Be sure to watch his excellent video demo embedded below. Continue reading “Orientation Aware Camera”