Horde3D

Hi everybody!

I am looking for an open source library to render graphics (convolution filter like blur, scaling + rotation, alpha compositing, etc.) with hardware acceleration (most likely OpenGL) for PAL video output via SDI at 25 fps. All of it will run on a linux box. One can think of it as a TV program generated from different data sources. There is no user input. It features an animated logo, playlist for songs, news ticker, webcam, and various similar stuff. The system must be able to run 24/7 with very little downtime.

I decided to go with an Open Source 3D engine, but I am not sure which tool is the right one for the job. It should provide the aforementioned effects and ideally some convenience functions like timers and image loaders. It should also be lightweight and conceptually mature. It does not need to contain full support for scenegraphs, because I do not need to render complex models.

Horde3d looks impressive at first glance, but is it adequate for my project? Any thoughts?

Thank you for your time, any help is very much appreciated.
Robert

Bear with me - I am not entirely familiar with the terminology. Basically, you have a linux box with a video card, and the video card is hooked up to a serial interface, which then delivers the video to TV/whatever?
Horde is certainly adequate, and it may also be overkill (not that overkill is a bad thing). You will have to write your filters yourself, using the shader framework, but there are many references around the web to help you.
You may have to perform careful memory logging of your application (and Horde) over an extended period to make sure you catch all memory leaks. I don't think Horde has any, but on the other hand, I never run it long enough for small leaks to be an issue.

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Tristam MacDonald - [swiftcoding]

Hi Robert
Lots of this stuff you could create by modifying the horde samples, but to really get what you want out of Horde you'll have to learn a little GLSL (OpenGL shading language). It's pretty easy to pick up though if you're familiar with graphics programming
The only thing required to generate a PAL signal is to correctly configure the aspect ratio when creating your camera in Horde. Normally (on PC) we only concern ourselves with the aspect of the screen (e.g. 4:3, 16:10, etc...), but PAL has rectangular pixels so you must account for pixel-aspect as well.

@swiftcoder:
- Yes, we use SDI (Serial Digital Interface, a standard used in professional TV production) to connect to the satellite uplink. Our current application is broadcasted over an Astra satellite.
- Regarding 24/7: Well, it is not only memory leaks, but resources in general. The final application will run as demon and needs to be really stable. Is Horde3d thouroughly tested, profiled and debugged?

@DarkAngel:
- Regarding PAL: Yes, aspect ratio is a concern. In OpenGL this is a matter of creating an appropriate viewport and frustum and as far as I see in Horde3d this is done with setupCameraView() and setupViewport(). However, there is also the need to control the framerate to get smooth movements.

Thank you for your answers!

We have an integrated memory leak check so that should not be a real problem. We also have a clean mechanism for creating and releasing resources (using reference counting) but I can't say that this is tested thoroughly. Horde is still under heavy refactoring so stability is not yet the main focus.