Method of rendering pixel-composited images for a graphics-based application running on a host computing system embodying a parallel graphics rendering system

Abstract

A multiple graphics processing unit (GPU) based parallel graphics system comprising multiple graphics processing pipelines with multiple GPUs supporting a parallel graphics rendering process having an object division mode of operation. Each GPU comprises video memory, a geometry processing subsystem and a pixel processing subsystem. According to the principles of the present invention, pixel (color and z depth) data buffered in the video memory of each GPU is communicated to the video memory of a primary GPU, and the video memory and the pixel processing subsystem in the primary GPU are used to carry out the image recomposition process, without the need for dedicated or specialized apparatus.

1 . A method of rendering pixel-composited images for a graphics-based application running on a host computing system embodying a parallel graphics rendering system,
 wherein said parallel graphics rendering system supports a parallel graphics rendering process using an object division mode of parallel computing operation, and wherein said parallel graphics rendering system includes a primary GPPL and at least one secondary GPPL, and   wherein each said GPPL includes (i) a GPU having a pixel processing subsystem provided with a programmable fragment shader, and (ii) video memory including a frame buffer (FB) having depth and color frame buffers for buffering pixel depth and color value, respectively,   said method comprising the steps of:
 (a) during the recompositing stage, moving the pixel Depth and Color values from said frame buffers in said secondary GPPL, to said frame buffers in said primary GPPL, by way of inter-GPPL communication; and 
 (b) merging said pixel depth and color values with their counterparts, within said frame buffer of said primary GPPL using said programmable fragment shader provided in said pixel processing subsystem. 
   
     
     
         2 . The method of  claim 1 , wherein steps (a) and (b) are carried out transparently to said graphics-based application. 
     
     
         3 . A method of rendering pixel-composited images for a graphics-based application running on a host computing system embodying a parallel graphics rendering system,
 wherein said parallel graphics rendering system supports a parallel graphics rendering process using an object division mode of parallel computing operation, and wherein said parallel graphics rendering system includes a primary GPPL and at least one secondary GPPL, and   wherein each said GPPL includes (i) a GPU having a geometry processing subsystem provided with a programmable vertex shader, and (ii) video memory including a frame buffer (FB) having depth and color frame buffers for buffering pixel depth and color value, respectively,   said method comprising the steps of:
 (a) during the recompositing stage, moving the pixel Depth and Color values from said frame buffers in said secondary GPPL, to said frame buffer in said primary GPPL, by way of inter-GPPL communication; and 
 (b) merging said pixel depth and color values with their counterparts, within said frame buffer of said primary GPPL using said programmable vertex shader supported in said pixel processing subsystem. 
   
     
     
         4 . The method of  claim 3 , wherein steps (a) and (b) are carried out transparently to said graphics-based application. 
     
     
         5 . A method of rendering pixel-composited images for a graphics-based application running on a host computing system embodying a parallel graphics rendering system,
 wherein said parallel graphics rendering system supports a parallel graphics rendering process using an object division mode of parallel computing operation, and wherein said parallel graphics rendering system includes a primary GPPL and at least one secondary GPPL, and   wherein each said GPPL includes (i) a GPU having a geometry processing subsystem provided with a programmable vertex shader, and a pixel processing subsystem provided with a programmable fragment shader, and (ii) video memory including a frame buffer (FB) having depth and color frame buffers for buffering pixel depth and color value, respectively, said method comprising the steps of:   (a) during the recompositing stage, moving the pixel Depth and Color values from said frame buffers in said secondary GPPL, to said frame buffers in said primary GPPL, by way of inter-GPPL communication; and   (b) merging said pixel depth and color values with their counterparts, within said frame buffer of said primary GPPL using both said programmable vertex shader provided in said geometry processing subsystem and said programmable fragment shader provided in said pixel processing subsystem.   
     
     
         6 . The method of  claim 5 , wherein steps (a) and (b) are carried out transparently to said graphics-based application.