Compression of surface normals in three-dimensional graphics data

A computer-implemented method for compressing a first three-dimensional surface normal corresponding to a graphical object, the method comprising:

• receiving first surface normal data which represents the first surface normal;
• compressing said first three-dimensional surface normal data into a first number of bits by:
• selecting a first subset of said first number of bits to indicate which one of a first plurality of subsets of all possible three-dimensional normals includes said first three-dimensional surface normal, wherein said wherein said compressing produces compressed first surface normal data;
• and
• transferring said compressed first surface normal data.

A computer-implemented method for compressing a first surface normal corresponding to a graphical object, comprising:

• receiving first surface normal data representing said first surface normal;
• compressing said first surface normal data by encoding information identifying a location of a first point on a surface of a predetermined sphere, wherein said compressing includes generating an index value and one or more mapping values;
• storing said index value and said one or more mapping values;
• wherein said index value is usable to select a fist set of intermediate surface normal data from a plurality of sets of intermediate surface normal data;
• and wherein said one or more mapping values are usable to generate decompressed surface normal data from said intermediate surface normal data.

A computer-implemented method for compressing a first three-dimensional surface normal corresponding to a graphical object, comprising:

• receiving first three-dimensional surface normal data representing said first surface normal;
• compressing said first surface normal data by encoding information identifying a location of a first point on a surface of a predetermined sphere, wherein said surface of said predetermined sphere represents all possible normalized three-dimensional surface normals wherein said compressing includes generating an index value and one or more mapping values;
• transferring said index value and said one or more mapping values;
• wherein said index value is usable to select a first set of intermediate surface normal data from a plurality of sets of intermediate surface normal data;
• and wherein said one or more mapping values are usable to generate decompressed surface normal data from said intermediate surface normal data.

A computer-implemented method for compressing a first three-dimensional surface normal corresponding to a graphical object, comprising:

• generating data representing a plurality of points located on a surface of a predetermined sphere, wherein said surface of said sphere represents all possible three-dimensional surface normals;
• storing data representing a subset of said plurality of points in a normal look-up table;
• receiving first surface normal data which represents said first surface normal;
• compressing said first surface normal data by encoding an index value and one or more mapping values;
• storing said index value and said one or more mapping values;
• wherein said index value is usable to select intermediate surface normal data from said data representing said subset of said plurality of points stored in said normal look-up table;
• and wherein said one or mapping values are usable to generate decompressed surface normal data from said intermediate surface normal data.

A memory media which stores program instructions for compressing a first surface normal corresponding to a graphical object, wherein said program instructions are executable to implement the steps of:

• receiving first surface normal data which represents said first surface normal;
• compressing said first three-dimensional surface normal data into a first number of bits by:
• selecting a first subset of said first number of bits to indicate which one of a first plurality of symmetrical subsets of all possible three-dimensional normals includes said first three-dimensional surface normal, wherein said compressing produces compressed first surface normal data;
• and
• storing said compressed first surface normal data.

A memory media which stores program instructions for compressing a three-dimensional first surface normal corresponding to a graphical object, wherein said program instructions are executable to implement the steps of:

• receiving first three-dimensional surface normal data which represents said first surface normal;
• compressing said first surface normal data into a first number of bits by:
• selecting a first subset of said first number of bits to indicate which one of a first plurality of symmetrical subsets of all possible three-dimensional normals includes said first three-dimensional surface normal, wherein said compressing produces compressed first surface normal data;
• and
• transferring said compressed first surface normal data.

A system for compressing a first three-dimensional surface normal corresponding to a graphical object, comprising:

• a receiving means for receiving first three-dimensional surface normal data which represents said first surface normal;
• a compressing means for compressing said first surface normal data utilizing characteristics of said first surface normal, wherein said compressing produces compressed first surface normal data by compressing a first set of three-dimensional surface normal data into a first number of bits by selecting a first subset of said first number of bits to indicate which one of a first plurality of symmetrical subsets of all possible three-dimensional normals includes said first three-dimensional surface normal;
• and
• a storing means for storing said compressed first surface normal data.

A system for compressing a first three-dimensional surface normal corresponding to a graphical object, comprising:

• a receiving means for receiving first three-dimensional surface normal data which represents said first three-dimensional surface normal;
• a compressing means for compressing said first surface normal data by compressing a first set of three-dimensional surface normal data into a first number of bits by selecting a first subset of said first number of bits to indicate which one of a first plurality of symmetrical subsets of all possible three-dimensional normals includes said first three-dimensional surface normal, wherein said compressing produces compressed first surface normal data;
• and
• a transferring means for storing said compressed first surface normal data.