Sun Microsystems, Inc.

Intel Corporation

Scott R Nelson

Michael Frank Deering

Wayne A Morse

N David Naegle

Nathaniel David Naegle

Marc R Tremblay

Michael G Lavelle

Subramania Sudharsanan

Kevin C Rushforth

Jeffrey Meng Wah Chan

Carol A Lavelle

Ewa M Kubalska

Nandini Ramani

Patrick Shehane

Lisa C Grenier

Huang Pan

Kevin Tang

David Naegle

Mike Lavelle

Mark Tian

Scott C Randolph

Don Peterson

A method and apparatus for efficiently performing graphic operations are provided. This is accomplished by providing a processor that supports any combination of the following instructions: parallel multiply-add, conditional pick, parallel averaging, parallel power, parallel reciprocal square root and parallel shifts.

Method and apparatus for parallel arithmetic operations

A sample-to-pixel calculation unit in a graphics system may comprise an adder tree. The adder tree includes a plurality of adder cells coupled in a tree configuration. Input values are presented to a first layer of adder cells. Each input value may have two associated control signals: a data valid signal and a winner-take-all signal. The final output of the adder tree equals (a) a sum of those input values whose data valid signals are asserted provided that none of the winner-take-all signals are asserted, or (b) a selected one of the input values if one of the winner-take-all bits is asserted. The selected input value is the one whose winner-take-all bit is set. The adder tree may be used to perform sums of weighted sample attributes and/or sums of coefficients values as part of pixel value computations.

Graphics system with an improved filtering adder tree

A graphics system and method for displaying lines on a display device. The system may comprise a sample buffer, a rendering unit and a sample-to-pixel calculation unit. The rendering unit may (a) generate a plurality of sample positions in a two-dimensional space, (b) determine a sample normal distance for each of the sample positions with respect to a line defined by the line-draw command, (c) assign sample values to the sample positions based on the sample normal distance of each of the sample positions, and (d) store the sample values in the sample buffer. The sample-to-pixel calculation unit may read sample values from the sample buffer, filter them to determine a pixel value, and transmit the pixel value to the display device. The rendering unit may render the line sample values with a narrower width to pre-compensate for the line-expanding effect of the filtering performed by the sample-to-pixel calculation unit.

Rendering lines with sample weighting

A dithering system comprising a dithering unit, a storage medium, and an averaging unit. The dithering unit is configured to receive a set of data values, to add dither values to the data values, and to truncate the resultant addition values to L-bit truncated values. The storage medium is configured to store the L-bit truncated values. The averaging unit is configured to read the L-bit truncated values from the storage medium, and to compute an average value using at least a subset of the L-bit truncated values. The dither values may have an average value of approximately one-half. The dither values may approximate a uniform distribution of numbers between &#x2212;A+&#xbd; and A+&#xbd;, wherein A is greater than or equal to one. Alternatively, the dithering unit may receive a temporal stream of data values, and the average unit may perform a temporal average (e.g. an FIR filter). The dithering system may be incorporated in a graphics system. In this case, data values may represent rendered sample values (e.g. color or alpha).

Recovering added precision from L-bit samples by dithering the samples prior to an averaging computation

A method and computer graphics system capable of implementing multiple pipelines for the parallel processing of graphics data. For certain data, a requirement may exist that the data be processed in order. The graphics system may use a set of tokens to reliably switch between ordered and unordered data modes. Furthermore, the graphics system may be capable of super-sampling and performing real-time convolution. In one embodiment, the computer graphics system may comprise a graphics processor, a sample buffer, and a sample-to-pixel calculation unit. The graphics processor may be configured to receive graphics data and to generate a plurality of samples for each of a plurality of frames. The sample buffer, which is coupled to the graphics processor, may be configured to store the samples. The sample-to-pixel calculation unit is programmable to generate a plurality of output pixels by filtering the rendered samples using a filter.

Graphics system configured to parallel-process graphics data using multiple pipelines

A method, apparatus, and system are described for processing an operation code (op-code) to be transmitted over a data path of a graphics pipeline. If the op-code comprises context state information for a first graphics context, then the context state information is transmitted to registers in the graphics pipeline over the graphics pipeline data path. If the op-code comprises a save state command, then context state information in the registers is retrieved and transmitted from the registers to a preallocated region of a frame buffer over the same graphics pipeline data path. If the op-code comprises a restore/load state command, then new context state information is loaded. Context state information for a second context can then be loaded on the graphics pipeline data path to restore or process a new context.

Automatic state savings in a graphics pipeline

A computer graphics system that utilizes a super-sampled sample buffer and a sample-to-pixel calculation unit for refreshing the display. The graphics system may have a graphics processor, a super-sampled sample buffer, and a sample-to-pixel calculation unit. The graphics processor renders samples into the sample buffer at computed positions or locations in the sample buffer. The graphics system may utilize a window ID that specifies attributes of pixels on a per object basis. The window ID may specify one or more of a sample mode, filter type, color attributes, or source attributes. The sample mode may include single sample per pixel mode and multiple samples per pixel mode. In implementing a single sample per pixel mode, the graphics system may be further operable to generate a single sample per pixel for certain windows of the screen in order to, for example, provide backwards compatibility with legacy systems with no multi-sampling support. The graphics system may generate samples that have the same value within the region of a single pixel, or the graphics system may utilize a very narrow filter that only selects the center sample in the averaging process.

Graphics system having a super-sampled sample buffer and having single sample per pixel support

A method, apparatus, and system are described for rasterizing a triangle. Pixel parameter values are interpolated by adding or subtracting a vertical delta and/or by adding or subtracting a horizontal delta within a 4&times;4 tile of 16 pixels.

Tile-based digital differential analyzer rasterization

A method and apparatus are provided for performing efficient conversion operations between floating point and fixed point values on a general purpose processor. This is achieved by providing an instruction for converting a fixed point value fx into a floating point value fl in a general purpose processor. Accordingly, the invention advantageously provides a general purpose processor with the ability to execute conversion operation between fixed-point and floating-point values with a single instruction compared with prior art general purpose processors that require multiple instructions to perform the same function. Thus, the general purpose processor of the present invention allows for more efficient and faster conversion operations between fixed-point and floating-point values.

Converting an arbitrary fixed point value to a floating point value

A computer graphics system that utilizes a super-sampled sample buffer and a sample-to-pixel calculation unit for refreshing the display. The graphics system may have a graphics processor, a super-sampled sample buffer, and a sample-to-pixel calculation unit. The graphics processor renders samples into the sample buffer and may utilize a window ID that specifies attributes of pixels on a per object basis. The window ID may specify one or more of a sample mode, filter type, color attributes, or source attributes. The sample mode may include single sample per pixel mode and multiple samples per pixel mode. The graphics system may be further operable to generate a single sample per pixel for certain windows of the screen in order to provide backwards compatibility with legacy systems.

Title-based digital differential analyzer rasterization

A computer graphics system may comprise a graphics processor, a sample buffer, and a sample-to-pixel calculation unit. The graphics processor renders samples into the sample buffer in response to received graphics data. The sample-to-pixel calculation unit generates a plurality of output pixels by filtering the rendered samples based on a filter function. The pixels may be computed by generating a weighted sum of sample values (e.g. red sample values) for samples falling within the filter support. The coefficients used in the weighted sum may be added to form a normalization factor. One weighted sum of sample values may be computed per pixel attribute such as red, green, blue and alpha. The normalization factor may be computed in parallel with one or more of the weighted sums. Normalized pixel values may be obtained by dividing the weighted-sums by the normalization factor.

Graphics system configured to filter samples using a variable support filter

A method, apparatus, and system are described for rasterizing a triangle. Pixel parameter values are interpolated by adding or subtracting a vertical delta or by adding or subtracting a horizontal delta within a 4&times;4 tile of 16 pixels.

A graphics system that is configured to utilize a sample buffer and a plurality of parallel sample-to-pixel calculation units, wherein the sample-pixel calculation units are configured to access different portions of the sample buffer in parallel. The graphics system may include a graphics processor, a sample buffer, and a plurality of sample-to-pixel calculation units. The graphics processor is configured to receive a set of three-dimensional graphics data and render a plurality of samples based on the graphics data. The sample buffer is configured to store the plurality of samples for the sample-to-pixel calculation units, which are configured to receive and filter samples from the sample buffer to create output pixels. Each of the sample-to-pixel calculation units are configured to generate pixels corresponding to a different region of the image. The region may be a vertical or horizontal stripe of the image, or a rectangular portion of the image. Each region may overlap the other regions of the image to prevent visual aberrations.

Growing community of inventors

Pleasanton, CA, United States of America

Scott R Nelson