Efficient triangular shaped meshes

• US 20040051715A1
• Filed: 09/12/2002
• Published: 03/18/2004
• Est. Priority Date: 09/12/2002
• Status: Active Grant

• Current Assignee: Activision Publishing Incorporated (Microsoft Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Johns, Charles Ray, Nutter, Mark Richard, Minor, Barry L., Brokenshire, Daniel Alan
• Granted Patent: US 7,209,137 B2
• Time in Patent Office: Days
• US Class Current: 345/582
• CPC Class Codes: G06T 15/00 3D [Three Dimensional] image rendering
• CPC Class Codes: G06T 17/20 Finite element generation, e.g. wire-frame surface description, tesselation

Abstract

The present invention renders a triangular mesh for employment in graphical displays. The triangular mesh comprises triangle-shaped graphics primitives. The triangle-shaped graphics primitives represent a subdivided triangular shape. Each triangle-shaped graphics primitive shares defined vertices with adjoining triangle-shaped graphics primitives. These shared vertices are transmitted and employed for the rendering of the triangle-shaped graphics primitives.

Claims

1. A method for employing video information associated with a triangular mesh, comprising:

deriving a plurality of adjacent triangle-shaped primitives of a first row, wherein each triangle-shaped primitive is defined as having both at least one lower vertex and at least one upper vertex;

caching both at least one lower vertex and at least one upper vertex of a selected triangle primitive of the first row;

overwriting at least one lower vertex of the selected triangle primitive with at least one upper vertex of the selected triangle primitive; and

caching one or more new upper vertexes of a selected triangle primitive of the next row, thereby generating a triangular mesh.

2. The method of claim 1, further comprising the step of rendering the triangular mesh.

3. The method of claim 1, wherein the step of deriving further comprises the step of subdividing a triangular shape into triangle primitives.

4. The method of claim 4, wherein the step of subdividing comprises creating a substantially equalized bisection.

5. The method of claim 4, wherein the subdividing comprises creating a substantially equalized n-section.

6. A method for transmitting display information, comprising:

subdividing a triangular shape into triangle primitives; and

rendering a triangular mesh from the plurality of triangle primitives.

7. The method of claim 6, wherein the subdividing comprises recursively performing substantially equalized bisections.

8. The method of claim 6, wherein the subdividing comprises creating a substantially equalized n-section.

9. The method of claim 6, wherein the step of subdividing further decomposes a subdivision into further subdivisions, but not exceeding the maximum receptive capacity of the vertex cache.

10. An apparatus for transmitting and rendering a triangular mesh comprising a plurality of graphics triangle primitives, the graphics triangle primitives having at least one lower and upper vertex, comprising:

a graphics processor, wherein the graphics processor is employable to derive a plurality of adjacent graphics triangle primitives; and

a display device employable to cache both the at least one lower vertex and at least one upper vertex of each triangle primitive, wherein the display device is further employable to overwrite at least one lower vertex of each graphics triangle primitive with at least one higher vertex of each triangle primitive, the display device still further employable to cache at least one new upper vertex of a triangle primitive of the next higher row.

11. The apparatus of claim 10, wherein the graphics processor is employable to subdivide a triangular shape from triangle primitives, thereby creating a triangular mesh.

12. The apparatus of claim 11, wherein the step of subdividing comprises creating a substantially equalized bisection.

13. The method of claim 11, wherein the step of subdividing comprises creating a substantially equalized n-section.

14. A method for employing protocol for the transmission and rendering of a triangular mesh, comprising:

a first rendering of one triangle primitive upon receipt of an upper vertex of a row, wherein the vertex of the row is not the last vertex of the row;

a second rendering of two triangle primitives upon receipt of the last upper vertex of a row; and

decrementing a mesh width after a row of vertices is received.

15. The method of claim 14, wherein the step of first rendering employs triangle primitives extendable to create a triangular mesh.

16. The method of claim 14, wherein a step of a subdividing decomposes a shape to be transmitted and rendered into subdivisions.

17. The method of claim 16, wherein the step of subdividing comprises creating a substantially equalized bisection.

18. The method of claim 16, wherein the subdividing comprises creating a substantially equalized n-section.

19. A computer program product for employing video information associated with a triangular mesh, the computer program product having a medium with a computer program embodied thereon, the computer program comprising:

computer code for deriving a plurality of adjacent triangle-shaped primitives of a first row, wherein each triangle-shaped primitive is defined as having both at least one lower vertex and at least one upper vertex;

computer code for caching both at least one lower vertex and at least one upper vertex of a selected triangle primitive of the first row;

computer code for overwriting at least one lower vertex of the selected triangle primitive with at least one upper vertex of the selected triangle primitive; and

computer code for caching one or more new upper vertexes of a selected triangle primitive of the next row, thereby generating a triangular mesh.

20. A processor for employing video information associated with a triangular mesh, the processor including a computer program comprising:

computer code for deriving a plurality of adjacent triangle-shaped primitives of a first row, wherein each triangle-shaped primitive is defined as having both at least one lower vertex and at least one upper vertex;

computer code for caching both at least one lower vertex and at least one upper vertex of a selected triangle primitive of the first row;

computer code for overwriting at least one lower vertex of the selected triangle primitive with at least one upper vertex of the selected triangle primitive; and

computer code for caching one or more new upper vertexes of a selected triangle primitive of the next row, thereby generating a triangular mesh.