摘要:
A system and method for performing zero-bandwidth-clears reduces external memory accesses by a graphics processor when performing clears and subsequent read operations. A set of clear values is stored in the graphics processor. Each portion of a color or z buffer may be configured using a zero-bandwidth-clear command to reference a clear value without writing the external memory. The clear value is provided to a requestor without accessing the external memory when a read access is performed.
摘要:
A system and method for performing zero-bandwidth-clears reduces external memory accesses by a graphics processor when performing clears and subsequent read operations. A set of clear values is stored in the graphics processor. Each region of a color or z buffer may be configured using a zero-bandwidth-clear command to reference a clear value without writing the external memory. The clear value is provided to a requestor without accessing the external memory when a read access is performed.
摘要:
A tiled graphics memory permits graphics data to be stored in different tile formats. One application is selecting a tile format optimized for the data generated for particular graphical surfaces in different rendering modes. Consequently, the tile format can be selected to optimize memory access efficiency and/or packing efficiency. In one embodiment a first tile format stores pixel data in a format storing two different types of pixel data whereas a second tile format stores one type of pixel data. In one implementation, a z-only tile format is provided to store only z data but no stencil data. At least one other tile format is provided to store both z data and stencil data. In one implementation, z data and stencil data are stored in different portions of a tile to facilitate separate memory accesses of z and stencil data.
摘要:
A system and method are described for compressing image data using a combination of compression methods. Compression method combinations are provided to compress image data of a particular frame buffer format and antialiasing mode. Each method in the compression method combination is tried in turn to compress the image data in a tile. The best method that succeeded in compressing the image data is encoded in the compression bit state associated with the tile. Together, the compression bits, the compression method combination, and the frame buffer format provide sufficient information to decompress a tile.
摘要:
A system and method are described for compressing image data using a combination of compression methods. Compression method combinations are provided to compress image data of a particular frame buffer format and antialiasing mode. Each method in the compression method combination is tried in turn to compress the image data in a tile. The best method that succeeded in compressing the image data is encoded in the compression bit state associated with the tile. Together, the compression bits, the compression method combination, and the frame buffer format provide sufficient information to decompress a tile.
摘要:
One embodiment of the present invention sets forth a technique for compressing color data. Color data for a tile including multiple samples is compressed based on an equality comparison and a threshold comparison based on a programmable threshold value. The equality comparison is performed on a first portion of the color data that includes at least exponent and sign fields of floating point format values or high order bits of integer format values. The threshold comparison is performed on a second portion of the color data that includes mantissa fields of floating point format values or low order bits of integer format values. The equality comparison and threshold comparison are used to select either computed averages of the pixel components or the original color data as the output color data for the tile. When the threshold is set to zero, only tiles that can be compressed without loss are compressed.
摘要:
One embodiment of the present invention sets forth a technique for compressing image data with high contrast between pixels within a tile and between samples within pixels without any data loss. Partial coverage layers are generated and written to a tile that includes multiple pixels without reading the existing image data that is stored for the tile. A partial coverage layer encodes image data, such as colors, and sub-pixel coverage information for each covered pixel in a tile. The use of partial coverage layers reduces the bandwidth used to store image data when a tile is not fully covered.
摘要:
A tiled graphics memory permits graphics data to be stored in different tile formats. One application is selecting a tile format optimized for the data generated for particular graphical surfaces in different rendering modes. Consequently, the tile format can be selected to optimize memory access efficiency and/or packing efficiency. In one embodiment a first tile format stores pixel data in a format storing two different types of pixel data whereas a second tile format stores one type of pixel data. In one implementation, a z-only tile format is provided to store only z data but no stencil data. At least one other tile format is provided to store both z data and stencil data. In one implementation, z data and stencil data are stored in different portions of a tile to facilitate separate memory accesses of z and stencil data.
摘要:
A system, method, and computer program product are provided for performing shadowing utilizing shadow maps and ray tracing. In operation, one or more shadow maps are rendered for at least one light source. Additionally, low confidence pixels associated with the one or more shadow maps are determined. Furthermore, shadow rays associated with the low confidence pixels are traced.
摘要:
A graphics system coalesces Z data and color data for a raster operations stage. The Z data and color data are stored in a memory aligned tile format. In one embodiment, rendering modes in which the tile does not have a data capacity corresponding to Z data or color data for a whole number of pixels have data for at least one pixel split across entries to improve packing efficiency. Rendering modes having a number of bits for Z data or color data that does not equal a power of two such as 24 bits, 48 bits, and 96 bits, may be implemented with a high packing efficiency in tile formats having a data capacity corresponding to a power of 2 bits.