Systems and methods for soft shadowing in 3-D rendering casting multiple rays from ray origins
AssigneeImagination Technologies Limited
InventorsJustin P. DeCell, Luke T. Peterson
Life of this patent
Estimating the term…
Abstract
Graphics processing systems and methods provide soft shadowing effects into rendered images. This is achieved in a simple manner which can be implemented in real-time without incurring high processing costs so it is suitable for implementation in low-cost devices. Rays are cast from positions on visible surfaces corresponding to pixel positions towards the center of a light, and occlusions of the rays are determined. The results of these determinations are used to apply soft shadows to the rendered pixel values.
Claims20
A machine-implemented method of graphics processing, comprising:
- determining whether a plurality of rays cast from surfaces in a scene are occluded from reaching a light, wherein each ray of the plurality of rays is associated with one or more pixels;
- for rays that are determined to be occluded from the light, recording a distance to its respective occlusion;
- for rays that are determined to be not occluded from the light, searching for one or more pixels associated with a ray that is determined to be occluded from the light, and if at least one pixel is found in the search, recording a distance based on one or more of the distances recorded for the at least one found pixel;
- and
- for rays for which a distance is recorded, using the recorded distance for the ray to determine shadowing for the one or more pixels associated with the ray.
A graphics processing unit configured to:
- determine whether a plurality of rays cast from surfaces in a scene are occluded from reaching a light, wherein each ray is associated with one or more pixels;
- for rays that are determined to be occluded from the light, record a distance to its respective occlusion;
- for rays that are determined to be not occluded from the light, search for one or more pixels associated with a ray that is determined to be occluded from the light, and if at least one pixel is found in the search, record a distance based on one or more of the distances recorded for the at least one found pixel;
- and
- for rays for which a distance is recorded, use the recorded distance for the ray to determine shadowing for the one or more pixels associated with the ray.
A non-transitory computer readable storage medium having stored thereon processor executable instructions that when executed cause at least one processor to:
- determine whether a plurality of rays cast from surfaces in a scene are occluded from reaching a light, wherein each of the rays is associated with one or more pixels;
- for rays that are determined to be occluded from the light, record a distance to its respective occlusion;
- for rays that are determined to be not occluded from the light, search for one or more pixels associated with a ray that is determined to be occluded from the light, and if at least one pixel is found in the search, record a distance based on one or more of the distances recorded for the at least one found pixel;
- and
- for rays for which a distance is recorded, use the recorded distance for the ray to determine shadowing for the one or more pixels associated with the ray.
Dependencies are inferred from the claim text.