Increasing the speed of computation of a volumetric scattering render technique

Abstract

Presented here is a system and method to increase the speed of computation of a volumetric scattering render technique. The volumetric scattering can include path tracing which simulates interactions between a virtual ray of light and a volume. The interaction can include reflection of the virtual ray of light of a particle within the volume. The system can obtain a threshold number of interactions between a virtual ray of light and a three-dimensional object through which the virtual ray of light is traveling. As the system performs the simulation, the system can compare a number of the interactions to the threshold number. Upon determining that the number of interactions is equal to or exceeds the threshold number, the system can terminate the simulation and approximate interactions between the virtual ray of light and the volume using a second rendering technique that is computationally less expensive than simulating the interactions.

1 . A system comprising:
 at least one hardware processor; and   at least one non-transitory memory storing instructions, which, when executed by the at least one hardware processor, cause the system to:
 render a first image of a three-dimensional object using a first rendering technique; 
 render a second image of the three-dimensional object using a second rendering technique; 
 render a third image of the three-dimensional object using a third rendering technique,
 wherein the second rendering technique and the third rendering technique are computationally less expensive than the first rendering technique; 
 
 based on the first image, the second image, and the third image, determine a combination including the second image and the third image,
 wherein the combination approximates an appearance of the first image; and 
 
 render multiple images using the combination including the second rendering technique and the third rendering technique,
 wherein rendering the multiple images using the combination including the second rendering technique and the third rendering technique is computationally less expensive than rendering the multiple images using the first rendering technique. 
 
   
     
     
         2 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image;   based on the second expected brightness and the third expected brightness determine a second weight associated with the second image and a third weight associated with the third image;   provide the first image, the second image and the third image to a user through a user interface;   provide the second weight in the third weight to the user through the user interface;   receive a modification to the second weight associated with the second image and a modification to the third weight associated with the third image via the user interface; and   determine the combination including the second image and the third image based on the second weight and the third weight.   
     
     
         3 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image; and   automatically determine how to combine the first image and the second image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         4 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image;   predict a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a number of simulated interactions between a virtual ray of light and the three-dimensional object,
 wherein the lower the number of simulated interactions the lower the second expected brightness and the third expected brightness; and 
   automatically determine how to combine the second image and the third image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         5 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image;   predict a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a size of the three-dimensional object, a scattering coefficient of the three-dimensional object, and an absorption coefficient of the three-dimensional object; and   automatically determine how to combine the first image and the second image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         6 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain an absorption coefficient associated with the three-dimensional object and a scattering coefficient associated with the three-dimensional object,
 wherein the absorption coefficient indicates a high amount of absorption and the scattering coefficient indicates a low amount of scattering; 
   determine that a second expected brightness of the second image and a third expected brightness of the third image match a first expected brightness of the first image; and   combine the second image in the third image using equal weights.   
     
     
         7 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a thickness of the three-dimensional object and a scattering coefficient associated with the three-dimensional object,
 wherein the thickness of the three-dimensional object indicates a thin object, and the scattering coefficient indicates a high amount of scattering; and 
   determine that a second expected brightness of the second image has lower brightness than a first expected brightness of the first image.   
     
     
         8 . The system of  claim 1 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 provide the first image, the second image and the third image to a user through a user interface;   receive a second weight associated with the second image and a third weight associated with the third image via the user interface; and   determine the combination including the second image and the third image based on the second weight and the third weight.   
     
     
         9 . A method comprising:
 rendering a first image of a three-dimensional object using a first rendering technique;   rendering a second image of the three-dimensional object using a second rendering technique;   rendering a third image of the three-dimensional object using a third rendering technique,
 wherein the second rendering technique and the third rendering technique are computationally less expensive than the first rendering technique; 
   based on the first image, the second image, and the third image, determining a combination including the second image and the third image,
 wherein the combination approximates an appearance of the first image; and 
   rendering multiple images using the combination including the second rendering technique and the third rendering technique,
 wherein rendering the multiple images using the combination including the second rendering technique and the third rendering technique is computationally less expensive than rendering the multiple images using the first rendering technique. 
   
     
     
         10 . The method of  claim 9 , wherein determining the combination including the second image and the third image comprises:
 obtaining a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image;   based on the second expected brightness and the third expected brightness determining a second weight associated with the second image and a third weight associated with the third image;   providing the first image, the second image and the third image to a user through a user interface;   providing the second weight in the third weight to the user through the user interface;   receiving a modification to the second weight associated with the second image and a modification to the third weight associated with the third image via the user interface; and   determining the combination including the second image and the third image based on the second weight and the third weight.   
     
     
         11 . The method of  claim 9 , wherein determining the combination including the second image and the third image comprises:
 obtaining a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image; and   automatically determining how to combine the first image and the second image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         12 . The method of  claim 9 , wherein determining the combination including the second image and the third image comprises:
 obtaining a first expected brightness associated with the first image;   predicting a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a number of simulated interactions between a virtual ray of light and the three-dimensional object,
 wherein the lower the number of simulated interactions the lower the second expected brightness and the third expected brightness; and 
   automatically determining how to combine the second image and the third image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         13 . The method of  claim 9 , wherein determining the combination including the second image and the third image comprises:
 obtaining a first expected brightness associated with the first image;   predicting a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a size of the three-dimensional object, a scattering coefficient of the three-dimensional object, and an absorption coefficient of the three-dimensional object; and   automatically determining how to combine the second image and the third image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         14 . At least one computer-readable storage medium, excluding transitory signals and carrying instructions, which, when executed by at least one data processor of a system, cause the system to:
 render a first image of a three-dimensional object using a first rendering technique;   render a second image of the three-dimensional object using a second rendering technique;   render a third image of the three-dimensional object using a third rendering technique,
 wherein the second rendering technique and the third rendering technique are computationally less expensive than the first rendering technique; 
   based on the first image, the second image, and the third image, determine a combination including the second image and the third image,
 wherein the combination approximates an appearance of the first image; and 
   render multiple images using the combination including the second rendering technique and the third rendering technique,
 wherein rendering the multiple images using the combination including the second rendering technique and the third rendering technique is computationally less expensive than rendering the multiple images using the first rendering technique. 
   
     
     
         15 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image;   based on the second expected brightness and the third expected brightness determine a second weight associated with the second image and a third weight associated with the third image;   provide the first image, the second image and the third image to a user through a user interface;   provide the second weight in the third weight to the user through the user interface;   receive a modification to the second weight associated with the second image and a modification to the third weight associated with the third image via the user interface; and   determine the combination including the second image and the third image based on the second weight and the third weight.   
     
     
         16 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image, a second expected brightness associated with the second image and a third expected brightness associated with the third image; and   automatically determine how to combine the first image and the second image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         17 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image;   predict a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a number of simulated interactions between a virtual ray of light and the three-dimensional object,
 wherein the lower the number of simulated interactions the lower the second expected brightness and the third expected brightness; and 
   automatically determine how to combine the second image and the third image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         18 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a first expected brightness associated with the first image;   predict a second expected brightness associated with the second image and a third expected brightness associated with the third image based on a size of the three-dimensional object, a scattering coefficient of the three-dimensional object, and an absorption coefficient of the three-dimensional object; and   automatically determine how to combine the second image and the third image based on the first expected brightness, the second expected brightness, and the third expected brightness,
 wherein a combination of the second expected brightness and the third expected brightness approximates the first expected brightness. 
   
     
     
         19 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 obtain a thickness of the three-dimensional object and a scattering coefficient associated with the three-dimensional object,
 wherein the thickness of the three-dimensional object indicates a thin object, and the scattering coefficient indicates a high amount of scattering; and 
   determine that a second expected brightness of the second image has lower brightness than a first expected brightness of the first image.   
     
     
         20 . The computer-readable storage medium of  claim 14 , wherein instructions to determine the combination including the second image and the third image comprise instructions to:
 provide the first image, the second image and the third image to a user through a user interface;   receive a second weight associated with the second image and a third weight associated with the third image via the user interface; and   determine the combination including the second image and the third image based on the second weight and the third weight.