Gallium3D

Gallium3D is a software library for 3D graphics acceleration, published as free software. Gallium 3D operates between the graphics API and the operating system with the primary goal of making driver development easier, bundling otherwise duplicated code of several different drivers at a single point. This is done by providing a better division of labour (for example, leaving memory management to the kernel DRI driver) and to support modern hardware architectures.

Gallium3D provides a unified API exposing standard hardware functions such as shader units found on modern hardware. Thus, 3D APIs such as OpenGL 1.x/2.x, OpenGL 3.x, OpenVG, GPGPU infrastructure or even Direct3D (as found in the Wine compatibility layer) will need only a single back-end, called state tracker, targeting Gallium3D API. By contrast Mesa 3D requires a different backend for each hardware platform, and several other APIs need translation to OpenGL at the expense of further overhead. In addition, using the modular structure of Gallium3D, there are works underway to leverage the LLVM compiler suite and create a module to optimize shader code on the fly.

Under Gallium3D, DRM (Direct Rendering Manager) kernel drivers will manage the memory, and DRI (Direct Rendering Interface) driver (now called DRI2) will be more GPU processing oriented. This will resolve memory management problems whose solutions are considered infeasible under Mesa 3D.

Current status

The first implemented and already partially working drivers are Cell and Intel GPU drivers. Work is done on ATI Radeon cards providing a skeleton driver, and the Nouveau team is moving development to Gallium3D, including a solution for older fixed function nVidia cards which lack programmable shaders.

External links

• Mesa 3D official page
• Gallium3D Tungstengraphics page
• Functional diagrams of Gallium3D
• Gallium 0.1 branch git repository on Freedesktop gitweb.
• An article on Gallium3D by Zack Rusin
• LWN article