Accelerated rendering of images with transparent pixels using a spatial index

• US 7,701,463 B2
• Filed: 05/09/2005
• Issued: 04/20/2010
• Est. Priority Date: 05/09/2005
• Status: Active Grant

• Current Assignee: Autodesk, Inc.
• Original Assignee: Autodesk, Inc.
• Inventors: Cochran, Benjamin D.
• Primary Examiner(s): Nguyen; Kimbinh T
• Application Number:
  US11/125,067
• Publication Number:
  US 20060262132A1
• Time in Patent Office: 1,807 Days
• Field of Search: 345/589, 345/592, 345/426, 345/419, 345/421, 345/598, 345/629, 707/102, 709/232
• US Class Current: 345/592
• CPC Class Codes: G09G 2340/12 Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels
• CPC Class Codes: G09G 5/36 characterised by the display of a graphic pattern, e.g. using an all-points-addressable [APA] memory

Abstract

A method, apparatus, and article of manufacture for accelerated rendering of images with transparent pixels using a spatial index. A determination is made whether anything exists behind an object in an image. If not, then transparent pixels within the object are converted to a background color and rendered as opaque pixels.

Claims

1. A computer-implemented method for rendering images containing transparent pixels, comprising:

(a) determining, by a computer, whether anything exists behind an object in an image; and

(b) converting, by the computer, transparent pixels within the object to a background color and rendering the transparent pixels as opaque pixels for display on a monitor connected to the computer, when nothing exists behind the object in the image.

2. The method of claim 1, wherein the determining step comprises determining whether the object is bottom-most in the image.

3. The method of claim 1, wherein the determining step comprises using a spatial index to determine whether anything exists behind the object in the image.

4. The method of claim 3, wherein the spatial index is an R-tree comprised of nodes, and each of the nodes represents a minimum bounding box for one or more objects in the image.

5. A computer-implemented apparatus for rendering images containing transparent pixels, comprising:

a computer;

means, performed by the computer, for;

(a) determining whether anything exists behind an object in an image; and

(b) converting transparent pixels within the object to a background color and rendering the transparent pixels as opaque pixels for display on a monitor connected to the computer, when nothing exists behind the object in the image.

6. The apparatus of claim 5, wherein the means for determining comprises means for determining whether the object is bottom-most in the image.

7. The apparatus of claim 5, wherein the means for determining comprises means for using a spatial index to determine whether anything exists behind the object in the image.

8. The apparatus of claim 7, wherein the spatial index is an R-tree comprised of nodes, and each of the nodes represents a minimum bounding box for one or more objects in the image.

9. An article of manufacture comprising a storage device for storing instructions that, when read and executed by a computer, result in the computer performing a method for rendering images containing transparent pixels, comprising:

(a) determining, by a computer, whether anything exists behind an object in an image;

(b) converting, by the computer, transparent pixels within the object to a background color and rendering the transparent pixels as opaque pixels for display on a monitor connected to the computer, when nothing exists behind the object in the image.

10. The article of claim 9, wherein the determining step comprises determining whether the object is bottom-most in the image.

11. The article of claim 9, wherein the determining step comprises using a spatial index to determine whether anything exists behind the object in the image.

12. The article of claim 11, wherein the spatial index is an R-tree comprised of nodes, and each of the nodes represents a minimum bounding box for one or more objects in the image.