Patch-division unit for high-order surface patch rendering systems
US6100894A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 1997 |
| Grant date | Aug 8, 2000 |
| Priority date | — |
| Expiry date | Aug 27, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A high order surface patch rendering system with adaptive tessellation. A patch is rendered by subdividing a patch until the subpatches are sufficiently flat that they can be approximated by a quadrilateral. To subdivide a patch, the patch rendering system uses a patch division unit which accepts the control points of a patch and divides the patch in half by determining the control points of a subpatch. The relationship of the patch to it's subpatches is that of a binary tree, where every patch division produces two subpatches which may themselves be subject to patch division. In one embodiment, the patch division unit is able to traverse the binary subdivision tree in three directions (parent to left-child, left-child to right-sibling, and right-sibling to parent) to minimize memory requirements. In this embodiment the patch division unit comprises a set of curve division units. An X-curve division unit is coupled to a patch buffer to receive current X coordinates for the set of control points for the current patch, and configured to convert the current X coordinates into new X coordinates for the control points of the new patch. A Y-curve division unit is coupled to the patch buf…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.