Corvalent Gator Mini-ITX, Руководство по установке

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Appendix D: On-Board Video
Appendix On-Board Video Controller
The Gator Mini-ITX has an On-board video controller. The On-board video controller is based on the Intel
82855GME GMCH.
Graphics Features
The GMCH IGD provides a highly integrated graphics accelerator delivering high performance 2D, 3D, and video
capabilities. With its interfaces to UMA using a DVMT configuration, an analog display and a LVDS port, the
GMCH can provide a complete graphics solution.
The GMCH also provides 2D hardware acceleration for block transfers of data (BLTs). The BLT engine provides
the ability to copy a source block of data to a destination and perform raster operations (e.g., ROP1, ROP2, and
ROP3) on the data using a pattern, and/or another destination. Performing these common tasks in hardware reduces
CPU load, and thus improves performance.
High bandwidth access to data is provided through the system memory interface. The GMCH uses Tiling
architecture to increase system memory efficiency and thus maximize effective rendering bandwidth. The Intel
855GME GMCH improves 3D performance and quality with 3D Zone rendering technology. The Intel 855GME
GMCH also supports Video Mixer rendering, and Bi-Cubic filtering.
3D/2D Instruction Processing
The GMCH contains an extensive set of instructions that control various functions including 3D rendering, BLT
operations, display, MPEG decode acceleration, and overlay. The 3D instructions set 3D pipeline states and control
the processing functions. The 2D instructions provide an efficient method for invoking BLT operations.
3D Engine
The 3D engine of the GMCH has been designed with a deeply pipelined architecture, where performance is
maximized by allowing each stage of the pipeline to simultaneously operate on different primitives or portions of the
same primitive. The GMCH supports the following:
•
Perspective-corrected Texture mapping
•
Multitexturing
•
Embossed and Dot-Product Bump mapping
•
Cubic Environment Maps
•
Bilinear, Trilinear, and Anisotropic MIP map filtering
•
Gouraud shading and Flat shading
•
Alpha-blending
•
Per-Vertex and per- pixel fog
•
Z/W buffering
These features are independently controlled via a set of 3D instructions. The 3D pipeline subsystem performs the 3D
rendering acceleration. The main blocks of the pipeline are the Setup Engine, Scan Converter, Texture Pipeline, and
Raster Pipeline. A typical programming sequence would be to send instructions to set the state of the pipeline
followed by rendering instructions containing 3D primitive vertex data.
2D Engine
The GMCH provides an extensive set of 2D instructions and 2D HW acceleration for block transfers of data (BLTs).
The BLT engine provides the ability to copy a source block of data to a destination and
perform operations (e.g., ROP1, ROP2, and ROP3) on the data using a pattern, and/or another destination. The
Stretch BLT engine is used to move source data to a destination that need not be the same size, with source
transparency. Performing these common tasks in hardware reduces CPU load, and thus improves performance.
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