Using a geometry shader for variable input and output algorithms

• US 9,536,275 B1
• Filed: 11/02/2007
• Issued: 01/03/2017
• Est. Priority Date: 07/31/2007
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Diard, Franck R.
• Primary Examiner(s): Hoang, Phi
• Application Number:
  US11/934,716
• Time in Patent Office: 3,350 Days
• Field of Search: 375/240, 345/422, 345/520
• US Class Current: 1/1
• CPC Class Codes: G06T 1/20 Processor architectures; Processor configuration, e.g. pipelining
• CPC Class Codes: G06T 15/005 General purpose rendering architectures
• CPC Class Codes: G06T 15/80 Shading
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 17/005 Tree description, e.g. octree, quadtree
• CPC Class Codes: G06T 2200/28 involving image processing hardware
• CPC Class Codes: G06T 2210/21 Collision detection, intersection
• CPC Class Codes: G06T 7/13 Edge detection

Abstract

A system and method uses the capabilities of a geometry shader unit within the multi-threaded graphics processor to implement algorithms with variable input and output.

Claims

1. A method for using a geometry shader unit to process input data and produce variable length output data, comprising:

receiving input data of a first length;

processing the input data using the geometry shader unit to produce the variable length output data of a second length, wherein the second length is determined based on data-dependent execution of the input data, and the second length is different than the first length; and

storing the variable length output data and information indicating the second length in a stream-out buffer.

2. The method of claim 1, further comprising the step of determining regions of an input image, wherein each region of the input image is represented by a portion of the input data.

3. The method of claim 2, further comprising the step of generating a vertex for each one of the regions to produce a set of vertices.

4. The method of claim 3, wherein the step of processing the input data comprises executing a geometry shader program for each vertex in the set of vertices to produce portions of the variable length output data.

5. The method of claim 4, wherein the geometry shader program is executed in parallel using a multithreaded processing core that is configured to allocate an execution thread to each vertex in the set of vertices.

6. The method of claim 4, wherein a y coordinate of each vertex in the set of vertices specifies a line in an output buffer where the portions of the variable length output data are written.

7. The method of claim 3, further comprising assigning a value to each vertex included in the set of vertices, wherein each value includes coordinates of boundaries of the region associated with the vertex.

8. The method of claim 1, further comprising the step of disabling clamping operations for the geometry shader unit.

9. The method of claim 1, further comprising the steps of storing the variable length output data in an output buffer.

10. The method of claim 1, wherein the variable length output data is a compressed version of the input data.

11. The method of claim 1, wherein the second length is a range determined by a bit depth of the input data.

12. A non-transitory computer readable medium including instructions that when executed by a geometry shader unit, cause the geometry shader unit to process input data and produce variable length output data, by performing the steps of:

receiving input data of a first length;

processing the input data using the geometry shader unit to produce the variable length output data of a second length, wherein the second length is determined based on data-dependent execution of the input data, and the second length is different than the first length; and

storing the variable length output data and information indicating the second length in a stream-out buffer.

13. The non-transitory computer readable medium of claim 12, further comprising the step of determining regions of an input image, wherein each region of the input image is represented by a portion of the input data.

14. The non-transitory computer readable medium of claim 13, further comprising the step of generating a vertex for each one of the regions to produce a set of vertices.

15. The non-transitory computer readable medium of claim 14, wherein the step of processing the input data comprises executing a geometry shader program for each vertex in the set of vertices to produce portions of the variable length output data.

16. The non-transitory computer readable medium of claim 15, wherein the geometry shader program is executed in parallel using a multithreaded processing core that is configured to allocate an execution thread to each vertex in the set of vertices.

17. The non-transitory computer readable medium of claim 16, wherein a y coordinate of each vertex in the set of vertices specifies a line in an output buffer where the portions of the variable length output data are written.

18. The non-transitory computer readable medium of claim 14, further comprising assigning a value to each vertex included in the set of vertices, wherein each value includes coordinates that indicate boundaries of the region associated with the vertex.