Creating a ray differential by accessing a G-buffer
A texture level of detail (LOD) approximation may be performed utilizing ray differentials and a G-buffer. For example, a scene to be rendered is identified, and a G-buffer of the scene is rendered. Additionally, ray tracing is started for the scene, and during the ray tracing, a ray differential is created by accessing the G-buffer. Further, the created ray differential is appended to a current ray, and the created ray differential is traced.
1. A method comprising:
identifying a scene to be rendered;
rendering a G-buffer of the scene;
starting ray tracing for the scene;
during the ray tracing, creating a ray differential for a pixel by accessing the G-buffer for the pixel and one or more additional pixels neighboring the pixel;
appending the created ray differential to a current ray; and
tracing the created ray differential.
2. The method of claim 1 , wherein the G-buffer is a screen-sized buffer generated using a pixel shader.
3. The method of claim 1 , wherein one or more attributes are written to the G-buffer for each pixel in the scene when the G-buffer of the scene is rendered.
4. The method of claim 1 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel to the right and to the left within the G-buffer in order to create the ray differential in a x-direction.
5. The method of claim 1 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel above and/or below within the G-buffer in order to create the ray differential in a y-direction.
6. The method of claim 1 , wherein G-buffer entries for pixels closest to the pixel both horizontally and vertically are accessed in order to create the ray differential in a x-direction and a y-direction.
7. The method of claim 1 , wherein a distance t to a hit point is stored in the G-buffer.
8. The method of claim 1 , wherein accessing the G-buffer for the pixel and one or more additional pixels neighboring the pixel includes accessing entries in the G-buffer for the pixel and one or more additional pixels neighboring the pixel, each entry of the entries storing a normal and a distance to a hit point for a corresponding pixel.
9. A system comprising:
a processor that is configured to:
identify a scene to be rendered;
render a G-buffer of the scene;
start ray tracing for the scene;
during the ray tracing, create a ray differential for a pixel by accessing the G-buffer for the pixel and one or more additional pixels neighboring the pixel;
append the created ray differential to a current ray; and
trace the created ray differential.
10. The system of claim 9 , wherein the G-buffer is a screen-sized buffer generated using a pixel shader.
11. The system of claim 9 , wherein one or more attributes are written to the G-buffer for each pixel in the scene when the G-buffer of the scene is rendered.
12. The system of claim 9 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel to the right and to the left within the G-buffer in order to create the ray differential in a x-direction.
13. The system of claim 9 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel above and/or below within the G-buffer in order to create the ray differential in a y-direction.
14. The system of claim 9 , wherein G-buffer entries for pixels closest to the pixel both horizontally and vertically are accessed in order to create the ray differential in a x-direction and a y-direction.
15. The system of claim 9 , wherein a distance t to a hit point is stored in the G-buffer.
16. A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, causes the processor to perform steps comprising:
identifying a scene to be rendered;
rendering a G-buffer of the scene;
starting ray tracing for the scene;
during the ray tracing, creating a ray differential for a pixel by accessing the G-buffer for the pixel and one or more additional pixels neighboring the pixel;
appending the created ray differential to a current ray; and
tracing the created ray differential.
17. The non-transitory computer-readable storage medium of claim 16 , wherein the G-buffer is a screen-sized buffer generated using a pixel shader.
18. The non-transitory computer-readable storage medium of claim 16 , wherein one or more attributes are written to the G-buffer for each pixel in the scene when the G-buffer of the scene is rendered.
19. The non-transitory computer-readable storage medium of claim 16 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel to the right and to the left within the G-buffer in order to create the ray differential in a x-direction.
20. The non-transitory computer-readable storage medium of claim 16 , wherein creating the ray differential by accessing the G-buffer includes accessing entries in the G-buffer for the pixel and the one or more additional pixels that neighbor the pixel above and/or below within the G-buffer in order to create the ray differential in a y-direction.
21. The non-transitory computer-readable storage medium of claim 16 , wherein G-buffer entries for pixels closest to the pixel both horizontally and vertically are accessed in order to create the ray differential in a x-direction and a y-direction.