Traversal method for a graphics display system
US4870599A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1986 |
| Grant date | Sep 26, 1989 |
| Priority date | — |
| Expiry date | Sep 26, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/04842
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for traversal of primitives in a graphics display system includes calculating pick data for a predetermined primitive, testing the primitive for invisibility, exiting to a next graphics order if the invisibility step is positive, testing the primitive for detectability, exiting to a next graphics order if the detectability test is false when traversal is performed for pick correlation purposes, determining whether a transformation environment update is required, recalculating the transformation environment if required, binding display attributes for the primitive and processing subsequent graphics orders to draw the primitive. Also, to eliminate unnecessary storing of registers when an execute structure is processed, a number of registers are set aside for storing control flags to selectively store registers into the stack. If a flag pick is zero the contents of the corresponding register will be stored on the stack. If the contents of the flag are one, indicating that the contents of the corresponding register has been stored on the stack, the contents will not be stored again, thus saving time and execution of the traversal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.