Other

Nintendo Co., Ltd.

Ati Technologies Inc.

Silicon Graphics, Incorporated

Artx

Anthony P DeLaurier

Timothy J Van Hook

Howard H Cheng

Robert J Moore

Carroll Philip Gossett

Genyo Takeda

Shuhei Kato

Nathan F Pooley

John Princen

Harold S Anderson

Stephen J Shepard

Jeffrey C Doughty

Byron Sheppard

Farhad Fouladi

Martin Hollis

Patrick Y Law

Robert A Drebin

Mark M Leather

John R Isidoro

Chris Brennan

Disclosed are methods and apparatus for accomplishing the fetching or sampling of channels of pixels or texels such as neighboring pixels or texels or non-neighboring pixels or texels in a simultaneous operation in order to achieve optimization of the performance of a texture pipeline. In particular, logic is disclosed including selector logic configured to retrieve data including a plurality of channels from each of a plurality of pixels or texels and operable to select one channel from the plurality of channels of the data from each of the pixels or texels. The logic also includes combination logic configured to combine two or more of the selected channels into a single vector, such as an RGBA vector representing the color.

Methods and apparatus for retrieving and combining samples of graphics information

A compact image element encoding format selectively allocates a bit field within the format to alternately encode either multi-bit alpha resolution or increased color resolution. This encoding technique may be advantageously used to allocate encoding bits to model semi-transparency while using those same bits for other purposes (e.g., higher color resolution) in instances where semi-transparency is not required (e.g., for opaque image elements). In one advantageous embodiment, the same encoding format can provide either RGB5 or RGB4A3, on an image-element-by-image-element basis. Applications include but are not limited to texture mapping in a 3D computer graphics system such as a home video game system or a personal computer.

Variable bit field color encoding

Variable bit field encoding

A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. The same texture mapping hardware used for color texturing provides resampled z texturing for sprites with depth or other applications. A z blender performs a z blending operation in screen space to blend surface z values with z texel values to provide per-pixel mapping of resampled z textures onto sampled 3D surface locations. Z texels can represent absolute depths or depth displacements relative to primitive surface depth. The z texel values may add to or replace primitive surface z values, and a constant bias may be added if desired. The resulting depth values are used for occlusion testing. Z textures can be generated by copying out portions of an embedded z buffer and providing the copied depth values to the texture mapping hardware. Multiple z texel formats are supported.

Z-texturing

High performance low cost video game system with coprocessor providing high speed efficient 3D graphics and digital audio signal processing

The invention provides a method of generating cache indexes that reduces the likelihood that adjacent addresses will map to the same cache regions. The hashing process is optimized to be sensitive to small changes in the input data so that similar sets of input data will preferably not result in the same or even similar output data. Memory accesses of the sort performed when rendering graphical images may involve numerous accesses to relatively similar memory locations Therefore, hashing of the index values that determine where the information from the memory locations will be stored while that information is in cache decreases the likelihood of similar memory locations being stored at the same cache location. Consequently, cache efficiency and performance is improved.

Method and apparatus for cache index hashing

The invention provides a method of operating a cache memory so that operation is optimized. Instead of fetching data immediately upon a cache miss, the present invention continues with subsequent cache accesses. Decoupled from cache access, cache misses are fetched to cache. During operation, for each request in a sequence of data requests, it is determined if the requested data can be found in cache memory. If the data is not found in the cache, the next request in the sequence is processed without first retrieving the data pending from the earlier request. A miss list is generated for each of the requests in the sequence of requests whose data is not found in the cache. The data that is associated with the requests in the miss list is obtained from DRAM and used to satisfy the requests. Some cache lines may have one or more pending hits to data associated with the cache line. Those requests are kept in a pending hits list and processed in order as required. There may also be pending misses kept in a pending misses list where the list contains one or more pending misses to data associated with the cache line. A flag or indicator is set for a cache line when there are misses associated with the cache line.

Method and apparatus for decoupled retrieval of cache miss data

The invention provides for cache organization of texture information and a method and apparatus for accessing cached texture information and an index for cached information. Texels are represented in two dimensions and stored in groups referred to as tiles. Cache is configured to contain multiple tiles of texture image data, each tile being stored as a line in the cache. A cache line can be multidimensional (e.g., two or three or more dimensions) and may be viewed as an identifiable storage element in the cache. Memory may consist of a plurality of cache lines. Direct mapped cache may be utilized wherein each DRAM location maps to a single cache line. A tag table contains the tag information for all tiles currently stored in cache. A portion of the texel information may be utilized as an index assigned to a specific cache line. Another portion of the tag information identifies the tile currently stored in cache. A portion of the S bits and a portion of the T bits are utilized as the index and tile information. The tags may be organized into sections (referred to as tag banks) with the cache lines interleaved in two dimensions across the tag banks. Additionally, when mipmapping, the level of detail may be specified as part of the tag information. Cache access requests that are not currently active may also be stored in an interleaved list or queue until they are completed.

Cache organization&mdash;direct mapped cache

A low cost high performance three dimensional (3D) graphics system can model a world in three dimensions and project the model onto a two dimensional viewing plane selected based on a changeable viewpoint. The viewpoint can be changed on an interactive, real time basis by operating user input controls such as game controllers. The system rapidly produces a corresponding changing image (which can include animated cartoon characters or other animation for example) on the screen of a color television set. The richly featured high performance low cost system gives consumers the chance to interact in real time inside magnificent virtual 3D worlds to provide a high degree of image realism, excitement and flexibility. An optimum feature set/architecture (including a custom designed graphics/audio coprocessor) provides high quality fast moving 3D images and digital stereo sound for video game play and other graphics applications.

Video game system and coprocessor for video game system

Video game system with coprocessor providing high speed efficient 3D graphics and digital audio signal processing

A low cost high performance three dimensional (3D) graphics system can model a world in three dimensions and project the model onto a two dimensional viewing plane selected based on a changeable viewpoint. The viewpoint can be changed on an interactive, real time basis by operating user input controls such as game controllers. The system rapidly produces a corresponding changing image (which can include animated cartoon characters or other animation) on the screen of a color television set. The richly featured high performance low cost system gives consumers the chance to interact in real time right inside magnificent virtual 3D worlds to provide a high degree of image realism, excitement and flexibility. An optimum feature set/architecture (including a custom designed graphics/audio coprocessor) provides high quality fast moving 3D images and digital stereo sound for video game play and other graphics applications. Numerous features provide flexibility and capabilities in a system within the cost range of most consumers.

A low cost high performance three dimensional (3D) graphics system is disclosed that can model a world in three dimensions and project the model onto a two dimensional viewing plane selected based on a changeable viewpoint. The viewpoint can be changed on an interactive, real time basis by operating user input controls such as game controllers. The system rapidly produces a corresponding changing image (which can include animated cartoon characters or other animation) on the screen of a color television set. The richly featured high performance low cost system is intended to give consumers the chance to interact in real time right inside magnificent virtual 3D worlds to provide a high degree of image realism, excitement and flexibility. An optimum feature set/architecture (including a custom designed graphics/audio coprocessor) provides high quality fast moving 3D images and digital stereo sound for video game play and other graphics applications. Numerous features provide flexibility and capabilities in a system that is intended to be within the cost range of most consumers.

Interface for a high performance low cost video game system with

Growing community of inventors

Sunnyvale, CA, United States of America

Anthony P DeLaurier