FrequentlyAskedQuestions

fr : Foire Aux Questions


An initial FAQ

Some frequently asked questions. Can't find your answer here? Try searching the wiki or visit the mailing list at http://lists.duskglow.com/mailman/listinfo/open-graphics.

*What is OGP, the Open Graphics Project?*

It is a project to produce a graphics development board, and then a graphics card with fully specified programming interfaces. This card will be optimized to be fast for current and next generation GUI environments. This means it is mostly designed for 3D operations, specifically those that are used to render GUIs (Graphical User Interfaces). It will accelerate games to varying degrees, but that is not its primary purpose. It is intended to be a well-documented card that can be easily _and reliably_ supported by open source operating systems.

*What is OGD?*

OGD is the Development Board used by the Open Graphics Project. OGD1 refers to the PCI based development board which will soon be available from Traversal Technology, the company founded by members of the Open Graphics Project.

*What is at the heart of the OGD card?*

the OGD development boards implement a fairly powerful FPGA (Field Programmable Gate Array). FPGAs are like the custom-made chips used in computers and other devices, but they can be reprogrammed at any time. This makes them wonderful for development, and hardware designs using them do not require high up-front costs to produce.

*What is the use of the OGD card?*

The OGP card is a powerful prototyping and development board, not a high powered graphics card for the end-user. Once the design is fleshed out and debugged, it will be fabbed as an ASIC? for lower per-part cost and higher performance,

* What is OGA?*

OGA is the Open Graphics Architecture. The RTL for OGA is already being released under a dual license (GPL and proprietary). Once the design is fleshed out and debugged, it will be fabbed as an ASIC? for lower per-part cost and higher performance.

* What is OGC?*

OGC is the Open Graphics Card This card will be more suitable for end users. An ASIC chipset is planned

* What is TRV10

A graphics card with OGA architecture sold by Traversal to the embedded market. Traversal Technology, the company founded by members of OGP have been contributing significant portions of code and employing the lead developer Timothy Miller and our Board designer Howard. By selling this graphics card to the embedded market they can support some of the developers who contribute to OGP and raise the funds toward an ASIC design.

See names and numbers for a list of nomenclature. Further refinements are expected.

* Are we going to get the 'source' for what is on the FPGA also?*

YES.

There are three different sets of "source code" that will be available:

source code to device drivers

• Source code to device drivers: All device driver code (including BIOS) written for the OGP will be released under an MIT or X11 licenses to encourage code to be shared and used freely in both open and in proprietary software.
• http://en.wikipedia.org/wiki/MIT_License
• http://www.gnu.org/licenses/info/X11.html

RTL for the FPGA-based product

• The RTL is the closest equivalent that hardware designs have to "source code", it's a C-like language called Verilog that describes circuit paths in the chip. The RTL for the FPGA-based product (a prototyping and development board) is already being released under a dual license (GPL and proprietary).

RTL for the ASIC.

• RTL for the ASIC will be released under a dual license (GPL and proprietary) There will be a time-delay on some parts (to deal with investor concerns over the $millions necessary to invest in fabrication), but once the investment is recouped, the code will be released. (We need a law firm to escrow the RTL for us, pro bono.)

*What is the deal with the dual license?*

In order for the hardware vendor (Traversal Technology) to have a profitable business model (something necessary to be able to spend $millions on ASIC fabrication), they will need to retain the right to sell the RTL and designs of their hardware to other companies under a closed license. (This does not extend to the software drivers which are always open source, under BSD and MIT licenses.) This licensing model is the same as what Troll Tech (Qt), Xara Xtreme and MySQL use for their software. This gives them the ability to license code as they need to, while allowing public access to the same source code under the GPL license.

Patches submitted via email or the mailing list must be signed off with a release, indicating that Traversal Technology has rights to use that code under the dual-licensing scheme. Code that is submitted directly to the SVN is signed off implicitly (by your act of submitting it). Those wishing to patch the code under other terms might start their own project or pay royalties.

*How much progress has been made?*

At present, we are working on the host interface (PCI, AGP, etc.) and the VGA core. These have been released under a dual license (GPL and proprietary). Traversal, the company founded by members of the Open Graphics Project, is currently testing the development board OGD1, also to be released under a dual license (GPL and proprietary).

The first development completed (by Timothy Miller) was called the "model". This is C++ code that documents the math and algorithms used in the final chip. At the right phase of the project, the model will be rewritten in Verilog (a hardware description language) and incorporated into the rest of the chip design. Nicolai H�hnle used that to write a first cut of a simulator of the finished chip. Client programs can connect to the simulator and command it to do things, just as a driver would tell the OGP card what to do. A screenshot of the simulator is shown here:



Eventually, this code will be interfaced with (( Mesa 3D )), a software OpenGL implementation, to provide a better test environment, and perhaps serve as the first cut of a driver for the card. For more information on the simulator, have a look at OpengraphicsSimulator.


For more information see our Road Map

*Will I be able to play Doom 3 with this hardware?*

At the time of this writing, there is no graphics card on the market on which you can play Doom 3 well while using open source drivers. With about 6.4 gigabytes/second memory bandwidth, our target for running the Linux Quake benchmark on our development card with the OGA1 GPU, is a frame rate of between 20 and 30 FPS on Quake III at 1280x1024.Source OGPN17 Future planned cards include PCIe and faster memory which means our graphics processor will only become faster.

See OGPN17 for the capabilities and performance targets of our development card OGD1

*Will this card support TV out?*

Head 0 gives you a choice between DVI and analog.
Head 1 gives you a choice between DVI and TV.
Heads 0 and 1 are independent of each other.

So, the answer is yes: Use head 0 for the DVI and head 1 for the TV, and you're all set. Effectively head 0 is DVI-I and head 1 is DVI-D.


Both the NTSC and PAL standards should be supported (and potentially SECAM too if possible).

Also check the planned features

*I don't see anything about DDC support?*

Don't worry, DDC is a given these days.

*How about PCI Express?*

A PCI Express version will exist. PCI and AGP versions will come first though.

*How about expandable memory, or a daughter board?*

The hardware required to interface these add-ons costs _more_ money than whatever part you are trying to save on. In the interest of keeping cost down, expandable memory won't happen. However this design is Open Hardware and you could certainly make a board that interfaces with the IDC compatible pins on OGD1.

*Why didn't you use some of XGI GPU's? They have open source drivers?*

In parallel to this development, we called XGI and talked to them about letting us resell their chip. They never got back with us. more .

*I'd like to help. What should I do?*

Thank you for joining us and for your kind offer to help. There's plenty to do. What you might want to do is lurk for a while and if you gravitate towards something, grab it. Some ideas are here: Contributing to OGP. And you could always post suggestions to the list.

*Okay. I know what I want to do to help and I need to get at the source code. What do I do?*

The source is stored in a Subversion repository, which is at https://svn.suug.ch/repos/opengraphics/main/trunk/ .

Instructions on how to check something out can be found in the Development_Tools page

NOTE: Anonymous users may download the source code and RTL and use it under the terms of the GPL license. Users who have write-access to the repository implicitly grant Traversal Technology "rights to use" under the dual license, when submitting changes to anything already under that dual license. (This is basically limited to the "model" and all RTL.)

*Are there other mailing lists associated with this project?*

Yes. See The Announce List and The SVN Commit List.