Methods and apparatus for visibility stream management

An apparatus for graphics processing, comprising:

• a memory;
• and
• at least one processor coupled to the memory and configured to:
• receive, at a tessellator, one or more primitives in an image;
• determine draw call visibility information for one or more draw calls, wherein the draw call visibility information includes information regarding whether the one or more draw calls are at least partially visible;
• identify the one or more draw calls as visible;
• generate a draw call visibility stream as part of a visibility stream hierarchy that includes the one or more draw calls;
• generate, at the tessellator, a plurality of sub-primitives including at least one visible sub-primitive and one non-visible sub-primitive associated with the one or more primitives, the plurality of sub-primitives corresponding to a plurality of tessellated primitives;
• determine visibility information for each of the plurality of sub-primitives, wherein the visibility information includes information regarding whether the sub-primitive is visible;
• identify one or more of the plurality of sub-primitives as visible based on the determined visibility information;
• determine a sub-primitive visibility stream as part of the visibility stream hierarchy including the one or more of the plurality of sub-primitives identified as visible, wherein the sub-primitive visibility stream is a level below the draw call visibility stream;
• render at least one of the one or more of the plurality of sub-primitives identified as visible in the sub-primitive visibility stream;
• identify at least one of the plurality of sub-primitives as not visible based on the determined visibility information;
• and
• mark the at least one of the plurality of sub-primitives identified as not visible.

An apparatus for graphics processing, comprising:

• means for receiving, at a tessellator, one or more primitives in an image;
• means for determining draw call visibility information for one or more draw calls, wherein the draw call visibility information includes information regarding whether the one or more draw calls are at least partially visible;
• means for identifying the one or more draw calls as visible;
• means for generating a draw call visibility stream as part of a visibility stream hierarchy that includes the one or more draw calls;
• means for generating, at the tessellator, a plurality of sub-primitives including at least one visible sub-primitive and one non-visible sub-primitive associated with the one or more primitives, the plurality of sub-primitives corresponding to a plurality of tessellated primitives;
• means for determining visibility information for each of the plurality of sub-primitives, wherein the visibility information includes information regarding whether the sub-primitive is visible;
• means for identifying one or more of the plurality of sub-primitives as visible based on the determined visibility information;
• means for determining a sub-primitive visibility stream as part of the visibility stream hierarchy including the one or more of the plurality of sub-primitives identified as visible, wherein the sub-primitive visibility stream is a level below the draw call visibility stream;
• rendering at least one of the one or more of the plurality of sub-primitives identified as visible in the sub-primitive visibility stream;
• identifying at least one of the plurality of sub-primitives as not visible based on the determined visibility information;
• and
• marking the at least one of the plurality of sub-primitives identified as not visible.

A non-transitory computer-readable medium storing computer executable code for graphics processing, comprising code to:

• receive, at a tessellator, one or more primitives in an image;
• determine draw call visibility information for one or more draw calls, wherein the draw call visibility information includes information regarding whether the one or more draw calls are at least partially visible;
• identify the one or more draw calls as visible;
• generate a draw call visibility stream as part of a visibility stream hierarchy that includes the one or more draw calls;
• generate, at the tessellator, a plurality of sub-primitives including at least one visible sub-primitive and one non-visible sub-primitive associated with the one or more primitives, the plurality of sub-primitives corresponding to a plurality of tessellated primitives;
• determine visibility information for each of the plurality of sub-primitives, wherein the visibility information includes information regarding whether the sub-primitive is visible;
• identify one or more of the plurality of sub-primitives as visible based on the determined visibility information;
• determine a sub-primitive visibility stream as part of the visibility stream hierarchy including the one or more of the plurality of sub-primitives identified as visible, wherein the sub-primitive visibility stream is a level below the draw call visibility stream;
• render at least one of the one or more of the plurality of sub-primitives identified as visible in the sub-primitive visibility stream;
• identify at least one of the plurality of sub-primitives as not visible based on the determined visibility information;
• and
• mark the at least one of the plurality of sub-primitives identified as not visible.