Redrawing recent curve sections for real-time smoothing
US9443332B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2016 |
| Grant date | Sep 13, 2016 |
| Priority date | — |
| Expiry date | Jan 29, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2200/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A recently rendered section of a curve is redrawn to smooth the curve on-the-fly while a user moves a stylus or other input device. On receiving data points for the curve, an old rendered section for prior data points is deleted by curve redrawing code, and a new spline that's visually smooth through the new data points and at least one prior data point is added. “Visually smooth” is defined using tangents. The rendered spline is a cardinal or other cubic Hermite spline. The curve is redrawn for display by overwriting frame buffer data. A single instruction multiple data processing architecture simultaneously calculates multiple data points for the new section of the curve rendering. A digital ink rendering uses a pen-tip shape or an arc shape, based on data point locations. The pen-tip shape simulates a square-tip pen, highlighter, pencil, charcoal, paintbrush, or liquid ink pen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.