Scalable desktop

• US 7,091,984 B1
• Filed: 03/11/2004
• Issued: 08/15/2006
• Est. Priority Date: 03/11/2004
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Clark, Richard L.
• Primary Examiner(s): Tung, Kee M.
• Assistant Examiner(s): RAHMJOO, MANUCHEHR
• Application Number:
  US10/798,521
• Time in Patent Office: 887 Days
• Field of Search: 345/427, 345/582, 345/660, 345/664, 345/587, 715/782
• US Class Current: 345/587
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2340/045 Zooming at least part of an image, i.e. enlarging it or shrinking it
• 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 5/14 Display of multiple viewports
• CPC Class Codes: G09G 5/363 Graphics controllers
• CPC Class Codes: G09G 5/397 Arrangements specially adapted for transferring the contents of two or more bit-mapped memories to the screen simultaneously, e.g. for mixing or overlay G09G5/02 takes precedence

Abstract

A method for displaying a desktop display surface. The method includes creating a render target surface having substantially the same dimensions as a desktop display surface, casting the desktop display surface as a texture, and setting the render target surface as a scanout read location. The method further includes creating a two dimensional rectangular object, rendering the two dimensional rectangular object by mapping the desktop display surface texture to the two dimensional rectangular object, storing the rendered two dimensional rectangular object to the render target surface and scanning out the rendered two dimensional rectangular object from the render target surface.

Claims

1. A method for displaying a desktop display surface having dimensions, comprising:

creating a render target surface having substantially the same dimensions as the desktop display surface;

casting the desktop display surface as a texture having the same dimensions as the desktop display surface;

determining a set of vertices that define a two dimensional rectangular object having the same dimensions as the desktop display surface;

rendering the two dimensional rectangular object by mapping at least a portion of the desktop display surface texture to the two dimensional rectangular object;

receiving a zoom factor, an offset in an x direction and an offset in a y direction;

calculating a texture addressing extent configured to determine the portion of the desktop display surface texture to be mapped to the two dimensional rectangular object;

calculating a set of texture addressing offsets in the x and y directions configured to provide the position on the desktop display surface texture from which the desktop display surface texture is to be mapped to the two dimensional rectangular object, wherein the texture addressing offset in the x direction is calculated as the offset in the x direction divided by the dimension of the desktop display surface in the x direction and the texture addressing offset in the y direction is calculated as the offset in the y direction divided by the dimension of the desktop display surface in the y direction; and

setting the render target surface as a scanout read location in preparation for displaying the desktop display surface.

2. The method of claim 1, further comprising storing the rendered two dimensional rectangular object to the render target surface.

3. The method of claim 1, further comprising:

storing the rendered two dimensional rectangular object to the render target surface; and

scanning out the rendered two dimensional rectangular object from the render target surface.

4. The method of claim 1, further comprising:

receiving a zoom factor and one or more offsets; and

creating the two dimensional rectangular object according to the dimensions of the desktop display surface, the zoom factor and the one or more offsets.

5. The method of claim 1, further comprising:

receiving a zoom factor and one or more offsets; and

calculating the texture addressing coordinates (u, v) of each vertex in the set of vertices as a function of the dimensions of the desktop display surface, the zoom factor and the offsets.

6. The method of claim 1, further comprising:

receiving a zoom factor and one or more offsets; and

calculating a texture addressing extent configured to determine the portion of the desktop display surface texture to be mapped to the two dimensional rectangular object.

7. The method of claim 6, wherein the texture addressing extent is equal to a texture addressing range divided by the zoom factor.

8. The method of claim 6, wherein the texture addressing extent is equal to a dimension of the desktop display surface divided by the zoom factor.

9. The method of claim 1, wherein creating the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for an upper left hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the x direction; and

setting a texture addressing coordinate v for the upper left hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the y direction.

10. The method of claim 1, wherein creating the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for an upper right hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the x direction plus the texture addressing extent; and

setting a texture addressing coordinate v for the upper right hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the y direction.

11. The method of claim 1, wherein creating the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for a bottom left hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the x direction; and

setting a texture addressing coordinate v for the bottom left hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the y direction plus the texture addressing extent.

12. The method of claim 1, wherein creating the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for a bottom right hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the x direction plus the texture addressing extent; and

setting a texture addressing coordinate v for the bottom right hand corner of the two dimensional rectangular object to be equal to the texture addressing offset in the y direction plus the texture addressing extent.

13. A method for displaying a desktop display surface, comprising:

receiving a zoom factor, an offset in an x direction and an offset in a y direction on the desktop display surface;

creating a two dimensional rectangular object having dimensions equal to dimensions of the desktop display surface;

computing a set of texture addressing coordinates for the two dimensional rectangular object using the dimensions of the desktop display surface, zoom factor, the offset in the x direction and the offset in the y direction;

casting a desktop display surface as a texture having dimensions equal to dimensions of the desktop display surface;

a rendering the two dimensional rectangular object by mapping at least a portion of the desktop display surface texture to the two dimensional rectangular object and calculating a texture addressing extent configured to determine the portion of the desktop display surface texture to be mapped to the two dimensional rectangular object; and

calculating a set of texture addressing offsets in the x and y directions configured to provide the position on the desktop display surface texture from which the desktop display surface texture is to be mapped to the two dimensional rectangular object, wherein the texture addressing offset in the x direction is calculated as the offset in the x direction divided by the dimension of the desktop display surface in the x direction and the texture addressing offset in the y direction is calculated as the offset in the y direction divided by the dimension of the desktop display surface in the y direction.

14. The method of claim 13, further comprising storing the rendered two dimensional rectangular object to a render target surface having substantially the same dimensions as the desktop display surface.

15. The method of claim 14, further comprising scanning out the rendered two dimensional rectangular object from the render target surface.

16. The method of claim 13, wherein the set of texture addressing coordinates includes texture addressing coordinates (u, v) for an upper right hand corner, an upper left hand corner, a bottom left hand corner and a bottom right hand corner of the two dimensional rectangular object.

17. The method of claim 13, wherein computing a set of texture addressing coordinates for the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for an upper left hand corner of the two dimensional rectangular object to be equal to the offset in the x direction divided by the dimension of the desktop display surface in the x direction; and

setting a texture addressing coordinate v for the upper left hand corner of the two dimensional rectangular object to be equal to the offset in the y direction divided by the dimension of the desktop display surface in the y direction.

18. The method of claim 13, wherein computing a set of texture addressing coordinates for the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for an upper right hand corner of the two dimensional rectangular object to be equal to the offset in the x direction divided by the dimension of the desktop display surface in the x direction plus the inverse of the zoom factor; and

setting a texture addressing coordinate v for the upper right hand corner of the two dimensional rectangular object to be equal to the offset in the y direction divided by the dimension of the desktop display surface in the y direction.

19. The method of claim 13, wherein computing a set of texture addressing coordinates for the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for a bottom left hand corner of the two dimensional rectangular object to be equal to the offset in the x direction divided by the dimension of the desktop display surface in the x direction; and

setting a texture addressing coordinate v for the bottom left hand corner of the two dimensional rectangular object to be equal to the offset in the y direction divided by the dimension of the desktop display surface in the y direction plus the inverse of the zoom factor.

20. The method of claim 13, wherein computing a set of texture addressing coordinates for the two dimensional rectangular object comprises:

setting a texture addressing coordinate u for a bottom right hand corner of the two dimensional rectangular object to be equal to the offset in the x direction divided by the dimension of the desktop display surface in the x direction plus the inverse of the zoom factor; and

setting a texture addressing coordinate v for the bottom left hand corner of the two dimensional rectangular object to be equal to the offset in the y direction divided by the dimension of the desktop display surface in the y direction plus the inverse of the zoom factor.

21. A computer system, comprising:

a processor; and

a memory comprising program instructions executable by the processor to;

create a render target surface having substantially the same dimensions as the desktop display surface;

cast the desktop display surface as a texture having the same dimensions as the desktop display surface;

determine a set of vertices that define a two dimensional rectangular object having the same dimensions as the desktop display surface;

render the two dimensional rectangular object by mapping at least a portion of the desktop display surface texture to the two dimensional rectangular object;

calculate a texture addressing extent configured to determine the portion of the desktop display surface texture to be mapped to the two dimensional rectangular object;

calculate a set of texture addressing offsets in the x and V directions configured to provide the position on the desktop display surface texture from which the desktop display surface texture is to be mapped to the two dimensional rectangular object, wherein the texture addressing offset in the x direction is calculated as the offset in the x direction divided by the dimension of the desktop display surface in the x direction and the texture addressing offset in the y direction is calculated as the offset in the y direction divided by the dimension of the desktop display surface in the y direction; and

set the render target surface as a scanout read location in preparation for displaying the desktop display surface.

22. The method of claim 21, wherein the memory further comprises program instructions executable to:

store the rendered two dimensional rectangular object to the render target surface; and

scan out the rendered two dimensional rectangular object from the render target surface.