Dynamic rendering of ink strokes with transparency

• US 7,091,963 B2
• Filed: 02/04/2004
• Issued: 08/15/2006
• Est. Priority Date: 08/01/2001
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Dresevic, Bodin, Kallay, Michael
• Primary Examiner(s): Osorio, Ricardo
• Assistant Examiner(s): Sheng, Tom
• Application Number:
  US10/770,448
• Publication Number:
  US 20040155904A1
• Time in Patent Office: 923 Days
• Field of Search: 345/173, 345/726, 345/764, 345/768, 345/592, 345/634, 345/637, 178/18.01, 178/18.03, 178/18.05, 178/18.06, 178/19.01, 178/19.03, 178/19.04, 178/19.05
• US Class Current: 345/173
• CPC Class Codes: G06T 11/203 Drawing of straight lines or curves

Abstract

Apparatus and methods for dynamically rendering transparent ink strokes, in some situations such that the rendered ink stroke has transparency similar to physical ink while it is being drawn. For example, the ink stroke may be dynamically rendered as a stroke having uniform transparency while it is being drawn. Only the new ink segment that has most recently been added to the stroke may be drawn, and areas of the new ink segment that overlap older segments of the ink stroke may be frozen, or excluded from being repainted.

Claims

1. A method for dynamically rendering a digital ink stroke, comprising the steps of:

receiving a new pen tip instance;

determining a first region based on the new pen tip instance;

determining a second region based on a previous pen tip instance;

freezing a color of each of a plurality of pixels within an intersection of the first and second regions; and

painting the first region while the color of the pixels within the intersection is frozen, wherein said painting the first region comprises applying a new color setting to a plurality of pixels that are within a third region preceding the second region.

2. The method of claim 1, wherein the second region is a combined set of regions including at least one previous pen tip instance.

3. The method of claim 2, wherein the second region is a union of the set of regions.