Optimized shadows in a foveated rendering system

Patent metadata

Field	Value
Publication number	US-10650544-B2
Application number	US-201715727505-A
Country	US
Kind code	B2
Filing date	Oct 6, 2017
Priority date	Jun 9, 2017
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A method for implementing a graphics pipeline. The method includes building a first shadow map of high resolution, and building a second shadow map based on the first shadow map of lower resolution. The method includes determining a light source affecting a virtual scene, and projecting geometries of objects of an image of the virtual scene onto a plurality of pixels of a display from a first point-of-view. The method includes determining a foveal region when rendering the image, wherein the foveal region corresponds to where an attention of a user is directed. The method includes determining a first set of geometries is drawn to a first pixel, determining the first set of geometries is in shadow based on the light source, and determining the first set of geometries is outside of the foveal region. The method includes rendering the first set of geometries using the second shadow map.

First claim

What is claimed is:

1. A method for implementing a graphics pipeline, comprising:
building a first shadow map of high resolution;
building a second shadow map based on the first shadow map, wherein the second shadow map has a lower resolution than the first shadow map;
determining a light source affecting a virtual scene;
projecting geometries of objects of an image of the virtual scene onto a plurality of pixels of a display from a first point-of-view;
determining a first set of geometries is drawn to a first pixel, wherein the first set of geometries includes at least one fragment;
determining the first set of geometries is in shadow based on the light source;
determining a foveal region when rendering the image of the virtual scene, wherein the foveal region corresponds to where an attention of a user is directed using a fragment shader of the graphics pipeline;
determining the first set of geometries is outside of the foveal region using the fragment shader;
rendering the first set of geometries for the first pixel using the second shadow map; and
disabling other shadowing effects during rendering of the first set of geometries for the first pixel.

2. The method of claim 1 , further comprising:
determining that a second set of geometries is drawn to a second pixel;
determining the second set of geometries is inside the foveal region; and
rendering the second set of geometries for the second pixel using the first shadow map.

3. The method of claim 1 , further comprising:
building a series of shadow maps based on distances from the foveal region, wherein resolutions of shadow maps in the series decrease as corresponding distances from the foveal region increases;
determining a third set of geometries is drawn to a third pixel that is outside the foveal region;
determining that the third set of geometries is in shadow based on the light source;
determining a distance of the third set of geometries as drawn in the third pixel from the foveal region;
selecting a third shadow map from the series of shadow maps based on the distance of the third set of geometries; and
rendering the third set of geometries for the third pixel using the third shadow map.

4. The method of claim 1 , further comprising:
centering the foveal region to a center of the display, wherein the foveal region is static.

5. The method of claim 1 , further comprising:
tracking gaze of the user viewing the virtual scene, wherein the gaze indicates a direction into the virtual scene towards which the attention of the user is directed;
determining a first direction of the user viewing the image of the virtual scene; and
centering the foveal region in the image based on the first direction.

6. The method of claim 1 , wherein the display comprises a head mounted display.

7. 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 implementing a graphics pipeline, comprising:
building a first shadow map of high resolution;
building a second shadow map based on the first shadow map, wherein the second shadow map has a lower resolution than the first shadow map;
determining a light source affecting a virtual scene;
projecting geometries of objects of an image of the virtual scene onto a plurality of pixels of a display from a first point-of-view;
determining a first set of geometries is drawn to a first pixel, wherein the first set of geometries includes at least one fragment;
determining the first set of geometries is in shadow based on the light source;
determining a foveal region when rendering the image of the virtual scene, wherein the foveal region corresponds to where an attention of a user is directed using a fragment shader of the graphics pipeline;
determining the first set of geometries is outside of the foveal region using the fragment shader;
rendering the first set of geometries for the first pixel using the second shadow map; and
disabling other shadowing effects during rendering of the first set of geometries for the first pixel.

8. The computer system of claim 7 , wherein the method further comprises:
determining that a second set of geometries is drawn to a second pixel;
determining the second set of geometries is inside the foveal region; and
rendering the second set of geometries for the second pixel using the first shadow map.

9. The computer system of claim 7 , wherein the method further comprises:
building a series of shadow maps based on distances from the foveal region, wherein resolutions of shadow maps in the series decrease as corresponding distances from the foveal region increases;
determining a third set of geometries is drawn to a third pixel that is outside the foveal region;
determining that the third set of geometries is in shadow based on the light source;
determining a distance of the third set of geometries as drawn in the third pixel from the foveal region;
selecting a third shadow map from the series of shadow maps based on the distance of the third set of geometries; and
rendering the third set of geometries for the third pixel using the third shadow map.

10. The computer system of claim 7 , wherein the method further comprises:
centering the foveal region to a center of the display, wherein the foveal region is static.

11. The computer system of claim 7 , wherein the method further comprises:
tracking gaze of the user viewing the virtual scene, wherein the gaze indicates a direction into the virtual scene towards which the attention of the user is directed;
determining a first direction of the user viewing the image of the virtual scene; and
centering the foveal region in the image based on the first direction.

12. The computer system of claim 7 , wherein in the method the display comprises a head mounted display.

13. A non-transitory computer-readable medium storing a computer program for implementing a graphics pipeline, the computer-readable medium comprising:
program instructions for building a first shadow map of high resolution;
program instructions for building a second shadow map based on the first shadow map, wherein the second shadow map has a lower resolution than the first shadow map;
program instructions for determining a light source affecting a virtual scene;
program instructions for projecting geometries of objects of an image of the virtual scene onto a plurality of pixels of a display from a first point-of-view;
program instructions for determining a first set of geometries is drawn to a first pixel wherein the first set of geometries includes at least one fragment;
program instructions for determining the first set of geometries is in shadow based on the light source;
program instructions for determining a foveal region when rendering the image of the virtual scene, wherein the foveal region corresponds to where an attention of a user is directed using a fragment shader of the graphics pipeline;
program instructions for determining the first set of geometries is outside of the foveal region using the fragment shader;
program instructions for rendering the first set of geometries for the first pixel using the second shadow map; and
program instructions for disabling other shadowing effects during rendering of the first set of geometries for the first pixel.

14. The computer-readable medium of claim 13 , further comprising:
program instructions for determining that a second set of geometries is drawn to a second pixel;
program instructions for determining the second set of geomet

Assignees

• Sony Interactive Entertainment Inc

Inventors

• Young Andrew
• Ho Chris
• Stafford Jeffrey Roger

Classifications

• G06T13/80

  Two-dimensional [2D] animation, e.g. using sprites · CPC title

• G06T7/0002

  Inspection of images, e.g. flaw detection · CPC title

• G06T2210/36

  Level of detail · CPC title

• G06T2215/12

  Shadow map, environment map · CPC title

• G06T11/20

  Drawing from basic elements · CPC title