Interfaces—Processor

Vertex Shader (VS) Stage

The VS stage performs shading of vertices output by the VF function. The VS unit produces an output vertex reference for every input vertex reference received from the VF unit, in the order received.

Geometry Shader (GS) Stage

The GS stage receives inputs from the VS stage. Compiled application-provided GS programs, specifying an algorithm to convert the vertices of an input object into some output primitives. For example, a GS shader may convert lines of a line strip into polygons representing a corresponding segment of a blade of grass centered on the line. Or it could use adjacency information to detect silhouette edges of triangles and output polygons extruding out from the edges.

Clip Stage

The Clip stage performs general processing on incoming 3D objects. However, it also includes specialized logic to perform a Clip Test function on incoming objects. The Clip Test optimizes generalized 3D Clipping. The Clip unit examines the position of incoming vertices, and accepts/rejects 3D objects based on its Clip algorithm.

Strips and Fans (SF) Stage

The SF stage performs setup operations required to rasterize 3D objects. The outputs from the SF stage to the Windower stage contain implementation-specific information required for the rasterization of objects and also supports clipping of primitives to some extent.

Windower / IZ (WIZ) Stage

The WIZ unit performs an early depth test, which removes failing pixels and eliminates unnecessary processing overhead.

The Windower uses the parameters provided by the SF unit in the object-specific rasterization algorithms. The WIZ unit rasterizes objects into the corresponding set of pixels. The Windower is also capable of performing dithering, whereby the illusion of a higher resolution when using low-bpp channels in color buffers is possible. Color dithering diffuses the sharp color bands seen on smooth-shaded objects.

Video Engine

The Video Engine handles the non-3D (media/video) applications. It includes support for VLD and MPEG2 decode in hardware.

2D Engine

The 2D Engine contains BLT (Block Level Transfer) functionality and an extensive set of 2D instructions. To take advantage of the 3D during engine’s functionality, some BLT functions make use of the 3D renderer.

Processor Graphics VGA Registers

The 2D registers consists of original VGA registers and others to support graphics modes that have color depths, resolutions, and hardware acceleration features that go beyond the original VGA standard.

 

Intel® Xeon® Processor E3-1200 v3 Product Family

June 2013

Datasheet – Volume 1 of 2

Order No.: 328907-001

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