Graphics library extensions
Methods for enabling graphics features in processors are described herein. Methods are provided to enable trinary built-in functions in the shader, allow separation of the graphics processor's address space from the requirement that all textures must be physically backed, enable use of a sparse buffer allocated in virtual memory, allow a reference value used for stencil test to be generated and exported from a fragment shader, provide support for use specific operations in the stencil buffers, allow capture of multiple transform feedback streams, allow any combination of streams for rasterization, allow a same set of primitives to be used with multiple transform feedback streams as with a single stream, allow rendering to be directed to layered framebuffer attachments with only a vertex and fragment shader present, and allow geometry to be directed to one of an array of several independent viewport rectangles without a geometry shader.
1. A method for graphics processing, comprising:
receiving a texture object including texture data;
receiving an allocation command; and
when the allocation command includes a sparse texture flag associated with the texture object, reserving processor address space for the texture data with uncommitted physical memory; and when the allocation command does not include a sparse texture flag associated with the texture object, reserving processor address space for the texture data with committed physical memory.
2. The method of claim 1 , further comprising:
receiving an image command; and
committing physical memory for the texture data in response to the image command.
3. The method of claim 2 , wherein the physical memory is committed on a condition that texture data is present.
4. The method of claim 2 , wherein the physical memory is decommitted on a condition that texture data is absent.
5. The method of claim 2 , wherein a commitment region is integer multiples of virtual page size in each dimension.
6. The method of claim 2 , further comprising:
decommitting the physical memory responsive to a second allocation command.
7. A processor, comprising:
a shader configured to receive a texture object including texture data;
the processor configured to receive an allocation command; and
when the allocation command includes a sparse texture flag associated with the texture object, the processor configured to reserve processor address space for the texture data with uncommitted physical memory; and when the allocation command does not include a sparse texture flag associated with the texture object, the processor configured to reserve processor address space for the texture data with committed physical memory.
8. The processor of claim 7 , further comprising:
the processor configured to receive an image command; and
the processor configured to commit physical memory for the texture data in response to the image command.
9. The processor of claim 8 , wherein the physical memory is committed on a condition that texture data is present.
10. The processor of claim 8 , wherein the physical memory is decommitted on a condition that texture data is absent.
11. The processor of claim 8 , wherein a commitment region is integer multiples of virtual page size in each dimension.
12. The processor of claim 8 , further comprising:
the processor configured to decommit the physical memory responsive to a second allocation command.