System and method for efficient multi-GPU rendering of geometry by performing geometry analysis while rendering

A non-transitory computer-readable medium storing a computer program for implementing a graphics pipeline, the computer-readable medium comprising:

• program instructions for rendering graphics for an application using a plurality of graphics processing units (GPUs);
• program instructions for using the plurality of GPUs in collaboration to render an image frame including a plurality of pieces of geometry;
• program instructions for using a previous assignment of the plurality of GPUs for rendering a previous image frame for initially assigning responsibility for the rendering of the plurality of pieces of geometry between the plurality of GPUs based on a plurality of screen regions, each GPU having a corresponding division of the responsibility such that a corresponding GPU is assigned to a first corresponding set of screen regions including one or more screen regions;
• program instructions for during a pre-pass phase of rendering that occurs before a geometry pass phase of rendering, generating information at the plurality of GPUs regarding relations of the plurality of pieces of geometry to the plurality of screen regions based on the initially assigning responsibility for the rendering of the plurality of pieces of geometry, wherein the pre-pass phase of rendering and the geometry pass phase of rendering are performed for the rendering of the plurality of pieces of geometry in a frame period to generate the image frame;
• program instructions for determining a plurality of computing costs for performing the rendering of the plurality of pieces of geometry of the image frame during the geometry pass phase;
• program instructions for reassigning in the frame period the plurality of screen regions to the plurality of GPUs before the geometry pass phase of rendering based on the information and the plurality of computing costs such that the corresponding GPU is assigned to a second corresponding set of screen regions including one or more screen regions for purposes of performing the geometry pass phase of rendering for the plurality of pieces of geometry;
• and
• performing at each of the plurality of GPUs the geometry pass phase of rendering on the plurality of pieces of geometry based on the information,
• wherein the reassigning the plurality of screen regions to the plurality of GPUs is performed for load balancing across the plurality of GPUs when rendering of the plurality of pieces of geometry, and
• wherein the rendering includes traversing a rendering command buffer a plurality of times, such that one or more screen regions having a higher cost are rendered during a first traversal, and remaining screen regions are rendered during a subsequent traversal.

A computer system comprising:

• a processor;
• memory coupled to the processor and having stored therein instructions that, if executed by the computer system, cause the computer system to execute a method for graphics processing, comprising:
• rendering graphics for an application using a plurality of graphics processing units (GPUs);
• using the plurality of GPUs in collaboration to render an image frame including a plurality of pieces of geometry;
• using a previous assignment of the plurality of GPUs for rendering a previous image frame for initially assigning responsibility for the rendering of the plurality of pieces of geometry between the plurality of GPUs based on a plurality of screen regions, each GPU having a corresponding division of the responsibility such that a corresponding GPU is assigned to a first corresponding set of screen regions including one or more screen regions;
• during a pre-pass phase of rendering that occurs before a geometry pass phase of rendering, generating information at the plurality of GPUs regarding relations of the plurality of pieces of geometry to the plurality of screen regions based on the initially assigning responsibility for the rendering of the plurality of pieces of geometry, wherein the pre-pass phase of rendering and the geometry pass phase of rendering are performed for the rendering of the plurality of pieces of geometry in a frame period to generate the image frame;
• determining a plurality of computing costs for performing the rendering of the plurality of pieces of geometry of the image frame during the geometry pass phase;
• reassigning in the frame period the plurality of screen regions to the plurality of GPUs before the geometry pass phase of rendering based on the information and the plurality of computing costs such that the corresponding GPU is assigned to a second corresponding set of screen regions including one or more screen regions for purposes of performing the geometry pass phase of rendering for the plurality of pieces of geometry;
• and
• performing at each of the plurality of GPUs the geometry pass phase of rendering on the plurality of pieces of geometry based on the information, wherein the reassigning the plurality of screen regions to the plurality of GPUs is performed for load balancing across the plurality of GPUs when rendering of the plurality of pieces of geometry, and
• wherein the rendering includes traversing a rendering command buffer a plurality of times, such that one or more screen regions having a higher cost are rendered during a first traversal, and remaining screen regions are rendered during a subsequent traversal.