| 81 |
|
The |
| 82 |
|
.I \-a |
| 83 |
|
option turns off reciprocity averaging for tensor tree output. |
| 84 |
< |
Normally on (+a), this ensures that the tensor BRDF obeys Helmholtz reciprocity. |
| 85 |
< |
However, in certain rare cases, reciprocity averaging can cause unwanted noise in the output. |
| 84 |
> |
Normally on (+a), this ensures that each tensor-tree hemisphere follows symmetry |
| 85 |
> |
implied by Helmholtz reciprocity, and is designed to reduce ray sampling noise. |
| 86 |
> |
However, for some systems, reciprocity averaging can actually make the output worse. |
| 87 |
|
.PP |
| 88 |
|
The geometry must fit a rectangular profile, whose width is along the X-axis, |
| 89 |
|
height is in the Y-axis, and depth is in the Z-axis. |
