Abstract: 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 graphics processor includes an embedded frame buffer for storing frame data prior to sending the frame data to an external location, such as main memory. A copy pipeline is provided which converts the data from one format to another format prior to writing the data to the external location. The conversion may be from one RGB color format to another RGB color format, from one YUV format to another YUV format, from an RGB color format to a YUV color format, or from a YUV color format to an RGB color format. The formatted data is either transferred to a display buffer, for use by the video interface, or to a texture buffer, for use as a texture by the graphics pipeline in a subsequent rendering process.

Abstract: A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. A relatively low chip-footprint, versatile texture environment (TEV) processing subsystem is implemented in a pipelined graphics system circulates computed color and alpha data over multiple texture blending/shading cycles (stages). The texture-environment subsystem combines per-vertex lighting, textures and constant (rasterized) colors to form computed pixel color prior to fogging and final pixel blending. Blending operations for color (RGB) and alpha components are independently processed by a single sub-blend unit that is reused over multiple processing stages to combine multiple textures.

Abstract: The present invention relates to a selectable multi-performance configuration. Instead of the traditional methods of producing separate high-end and low-end graphics chips, the present invention produces processing systems in a single unit. The single unit is readily and functionally partitionable. Each partition is capable of independent operation. By using all of the partitions a high-end graphics processing system may be simulated and tested. By using a subset of the partitions, a low-end graphics processing system may be simulated on the same system without the added cost of re-design of either hardware or software.

Abstract: The present invention relates to a rasterizer interpolator. In one embodiment, a setup unit is used to distribute graphics primitive instructions to multiple parallel rasterizers. To increase efficiency, the setup unit calculates the polygon data and checks it against one or more tiles prior to distribution. An output screen is divided into a number of regions, with a number of assignment configurations possible for various number of rasterizer pipelines. For instance, the screen is sub-divided into four regions and one of four rasterizers is granted ownership of one quarter of the screen. To reduce time spent on processing empty times, a problem in prior art implementations, the present invention reduces empty tiles by the process of coarse grain tiling. This process occurs by a series of iterations performed in parallel. Each region undergoes an iterative calculation/tiling process where coverage of the primitive is deduced at a successively more detailed level.

Abstract: A hardware-accelerated recirculating programmable texture blender/shader arrangement circulates computed color and alpha data over multiple texture blending/shading cycles (stages) to provide multi-texturing and other effects. Up to sixteen independently programmable consecutive stages, forming a chain of blending operations, are supported for applying multiple textures to a single object in a single rendering pass.

Abstract: 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 graphics pipeline renders and prepares images for display at least in part in response to polygon vertex attribute data and texel color data stored as a texture images in an associated memory. An efficient texturing pipeline arrangement achieves a relatively low chip-footprint by utilizing a single texture coordinate/data processing unit that interleaves the processing of logical direct and indirect texture coordinate data and a texture lookup data feedback path for “recirculating” indirect texture lookup data retrieved from a single texture retrieval unit back to the texture coordinate/data processing unit.

Abstract: Graphics processing circuitry includes processing circuitry operative to generate pixel information in response to primitive information, and a correction circuit, coupled to the processing circuitry, operative to generate gamma corrected pixel information in response to the pixel information. The correction circuit converts the floating point pixel information generated by the processing circuitry into a gamma corrected fixed-point value so that gamma space pixel data is stored in the frame buffer. This fixed point gamma corrected pixel information, converted from the floating point pixel information, compensates for the non-linear display characteristics exhibited by current display devices. This results in the display output being more accurate; thereby, improving the appearance quality of the resulting image.

Abstract: 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 system achieves highly efficient full-scene anti-aliasing by implementing a programmable-location super-sampling arrangement and using a selectable-weight vertical-pixel support area blending filter. For a 2×2 pixel group (quad), the locations of three samples within each super-sampled pixel are individually selectable. A twelve-bit multi-sample coverage mask is used to determine which of twelve samples within a pixel quad are enabled based on the portions of each pixel occupied by a primitive fragment and any pre-computed z-buffering. Each super-sampled pixel is filtered during a copy-out operation from a local memory to an external frame buffer using a pixel blending filter arrangement that combines seven samples from three vertically arranged pixels.

Abstract: 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. Emboss style effects are created using fully pipelined hardware including two distinct dot-product computation units that perform a scaled model view matrix multiply without requiring the Normal input vector and which also compute dot-products between the Binormal and Tangent vectors and a light direction vector in parallel. The resulting texture coordinate displacements are provided to texture mapping hardware that performs a texture mapping operation providing texture combining in one pass. The disclosed pipelined arrangement efficiently provides interesting embossed style image effects such as raised and lowered patterns on surfaces.

Abstract: 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. Realistic looking surfaces on rendered images are generated by EMBM using an indirect-texture lookup to a “bump map” followed by an environment or light mapping. Apparatus and example methods for environment-mapped style of bump-mapping (EMBM) are provided that use a pre-completed bump-map texture accessed as an indirect texture along with pre-computed object surface normals (i.e., the Normal, Tangent and Binormal vectors) from each vertex of rendered polygons to effectively generate a new perturbed Normal vector per vertex.

Abstract: The embodiments of the present invention are a method and apparatus to perform anti-aliasing using multi-sampling on a non-power-of-two pixel grid. Using the present invention with 6 sample multisampling gives the same visual antialiasing quality as 8 samples using a prior art technique but uses less memory. A non-power-of-two equally spaced sample from a conventional grid of size N×N, where N is 12 can be chosen using the present invention. A scan conversion to determine the set of pixels covered by a polygon is performed in two parts. According to one embodiment, the present invention can multiply and divide by “N” in order to multisample an image using samples per pixel chosen from a N×N sub-sample grid, where “N” is not necessarily a power of 2. The present invention performs the divide by “N” step, where the step is achieved using a quick divide by 3 or 12 technique.

Abstract: A method and apparatus for graphical processing. A logic core to perform pixel fragment manipulation and processing is instantiated on a single substrate with one or more memory units. The memory units are dynamically segmentable into frame buffer and texture memory. Because the logic core is on the same substrate as the memory units, the bandwidth between the core and the memory is greatly increased.

Abstract: Graphics processing circuitry includes processing circuitry operative to generate pixel information in response to primitive information, and a correction circuit, coupled to the processing circuitry, operative to generate gamma corrected pixel information in response to the pixel information. The correction circuit converts the floating point pixel information generated by the processing circuitry into a gamma corrected fixed-point value so that gamma space pixel data is stored in the frame buffer. This fixed point gamma corrected pixel information, converted from the floating point pixel information, compensates for the non-linear display characteristics exhibited by current display devices. This results in the display output being more accurate; thereby, improving the appearance quality of the resulting image.

Abstract: A graphics processing circuit includes at least two pipelines operative to process data in a corresponding set of tiles of a repeating tile pattern, a respective one of the at least two pipelines operative to process data in a dedicated tile, wherein the repeating tile pattern includes a horizontally and vertically repeating pattern of square regions. A graphics processing method includes receiving vertex data for a primitive to be rendered; generating pixel data in response to the vertex data; determining the pixels within a set of tiles of a repeating tile pattern to be processed by a corresponding one of at least two graphics pipelines in response to the pixel data, the repeating tile pattern including a horizontally and vertically repeating pattern of square regions; and performing pixel operations on the pixels within the determined set of tiles by the corresponding one of the at least two graphics pipelines.

Abstract: The present invention provides a solution to the problems of performing transformation functions on data originating in gamma space and part of systems that do not use, or are not intended to use, gamma correction schemes. The invention provides additional stages to a transform block used by a transform function. In the scheme of the invention, each input sample has a degamma function (inverse gamma) applied to it to transform it from gamma space to linear space, prior to the transform block. The degamma function is such as to approximate the transfer function of a typical monitor. After the transform operation is applied at the transform block to produce a result, a gamma function is applied to the result to return the sample to gamma space so that the output sample is ready for further processing.

Abstract: 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. Textured surfaces are created using indirect texture tiling. A set of direct and indirect texture coordinates are defined. The indirect coordinates are used in an indirect lookup operation in an indirect tile index map to obtain tile select offsets. The offsets are used to modify the direct texture coordinates, and the modified texture coordinates are then used to obtain a texture tile from a tile definitions map. The selected tile is then displayed. In another embodiment, the offsets are biased and combined with the direct texture coordinates to produce a second set of modified texture coordinates. The second set is used to obtain a second texture tile from the tile definitions map.

Abstract: 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.

Abstract: 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. A reconfigurable graphics pipeline has a hidden surface removal stage that may be placed at different locations within the pipeline depending on pipeline rendering mode. When the pipeline operates in certain rendering modes, the hidden surface removal operation can be performed early in the pipeline—allowing the pipeline to avoid wasting its time imaging obstructed surfaces. For other (e.g., alpha based) rendering modes, the hidden surface removal operation is performed near the end of the pipeline—when the pipeline has developed sufficient additional information required by the particular rendering mode to resolve depth comparisons.

Abstract: 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 graphics pipeline performs Z-buffering and optionally provides memory efficient full scene anti-aliasing (FSAA). When the anti-aliasing rendering mode is selected, Z value bit compression is performed to more efficiently make use of the available Z buffer memory. A Z-clamping arrangement is used to improve the precision of visually important Z components by clamping Z values to zero of pixels that fall within a predetermined Z-axis range near the Z=0 eye/camera (viewport) plane. This allows a Z-clipping plane to be used very close to the eye/camera plane—to avoid undesirable visual artifacts produced when objects rendered near to the eye/camera plane are clipped—while preserving Z value precision for the remaining depth of the scene.

Abstract: A method and apparatus for graphical processing. A logic core to perform pixel fragment manipulation and processing is instantiated on a single substrate with one or more memory units. The memory units are dynamically segmentable into frame buffer and texture memory. Because the logic core is on the same substrate as the memory units, the bandwidth between the core and the memory is greatly increased.