Kirk Steffen Haskell

US Patent:

60521295, Apr 18, 2000

Filed:

Oct 1, 1997

Appl. No.:

8/942078

Inventors:

Mark Christopher Fowler - Colchester VT
Kirk Steffen Haskell - Essex Junction VT
Robert Spencer Horton - Colchester VT
Thomas Yu-Kiu Kwok - Washington Township NJ
Chandrasekhar Narayanaswami - Wilton CT
Bengt-Olaf Schneider - Yorktown Heights NY
Mark Van Horn - Raleigh NC
James Lewis van Welzen - Raleigh NC

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06T 1530

US Classification:

345434

Abstract:

While executing the standard graphics processing steps, problem polygons (i. e. , those outside of a defined clip volume) are buffered for later processing, while the standard graphics processing continues, without the need for periodically reformatting data and performing clipping. After either a predefined number of polygons have been stored at the buffer location, or at such time as a change in the rendering state occurs, the buffered polygons are clipped.

US Patent:

6177944, Jan 23, 2001

Filed:

Sep 18, 1998

Appl. No.:

9/156934

Inventors:

Mark Christopher Fowler - Colchester VT
Kirk Steffen Haskell - Essex Junction VT
Robert Spencer Horton - Colchester VT
Thomas Yu-Kiu Kwok - Washington Township NJ
Steve Mastrianni - Unionville CT
Chandrasekhar Narayanaswami - Wilton CT
Bengt-Olaf Schneider - Yorktown Heights NY
Mark van Horn - Raleigh NC
James Lewis van Welzen - Longmont CO

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1500

US Classification:

345426

Abstract:

A method and apparatus for a computer graphics rendering system which slices the traditional geometry pipeline into two phases to improve overall graphics system utilization is described. The graphics system consists of a host processor and a graphics adapter. The host creates work items and feeds them to the graphics adapter. In the two phase method, the first phase computes the clipping status and immediately returns this status information, before completion of the actual clipping, to the application running on the host processor to minimize stalling the host processor and hence the application. The second phase performs the rest of the work necessary to draw the objects on the screen. The advantage of two phase method is that the host processor minimizes its wait (but only for model/view transformation and clipping status determination) for a return status from the graphics adapter for the current work item and gets to create the next work item from the application sooner.