Single pass bounding volume hierarchy rasterization

An apparatus for graphics processing, comprising:

• a memory configured to store a render target;
• at least one processor configured to:
• receive a source pixel value to be written to a pixel location in the render target, wherein the source pixel value is associated with a source node in a hierarchical structure having a plurality of nodes associated with a plurality of node indices, and wherein the source node is associated with a source node index made up of a first set of bits;
• receive a destination pixel value of the pixel location in the render target, wherein the destination pixel value is associated with a destination node in the hierarchical structure, and wherein the destination node is associated with a destination node index made up of a second set of bits;
• determine a lowest common ancestor node of the source node and the destination node in the hierarchical structure, including determining a resulting node index associated with the lowest common ancestor node based at least in part on a common set of bits between the first set of bits and the second set of bits;
• and
• output a resulting pixel value associated with the lowest common ancestor node of the source node and the destination node to the pixel location in the render target.

An apparatus for graphics processing, comprising:

• means for receiving a source pixel value to be written to a pixel location in a render target, wherein the source pixel value is associated with a source node in a hierarchical structure having a plurality of nodes associated with a plurality of node indices, and wherein the source node is associated with a source node index made up of a first set of bits;
• means for receiving a destination pixel value of the pixel location in the render target, wherein the destination pixel value is associated with a destination node in the hierarchical structure, and wherein the destination node is associated with a destination node index made up of a second set of bits;
• means for determining a lowest common ancestor node of the source node and the destination node in the hierarchical structure, the means for determining including means for determining a resulting node index associated with the lowest common ancestor node based at least in part on a common set of bits between the first set of bits and the second set of bits;
• and
• means for outputting, by the render output unit of the processor, a resulting pixel value associated with the lowest common ancestor node of the source node and the destination node to the pixel location in the render target.

A non-transitory computer-readable storage medium storing instructions that, when executed, cause one or more programmable processors to:

• receive a source pixel value to be written to a pixel location in a render target, wherein the source pixel value is associated with a source node in a hierarchical structure having a plurality of nodes associated with a plurality of node indices, and wherein the source node is associated with a source node index made up of a first set of bits;
• receive a destination pixel value of the pixel location in the render target, wherein the destination pixel value is associated with a destination node in the hierarchical structure, and wherein the destination node is associated with a destination node index made up of a second set of bits;
• determine a lowest common ancestor node of the source node and the destination node in the hierarchical structure, including determining a resulting node index associated with the lowest common ancestor node based at least in part on a common set of bits between the first set of bits and the second set of bits;
• and
• output a resulting pixel value associated with the lowest common ancestor node of the source node and the destination node to the pixel location in the render target.