| 12 |
|
|
| 13 |
|
/* |
| 14 |
|
* Clipping objects permit holes and sections to be taken out |
| 15 |
< |
* of other objects. The method is simple: |
| 15 |
> |
* of other objects. |
| 16 |
|
* |
| 17 |
|
* The argument is the clipped materials; |
| 18 |
|
* the first is used to shade upon exit. |
| 19 |
+ |
* |
| 20 |
+ |
* In the simple case of the first argument being "void", we |
| 21 |
+ |
* just add or subtract (depending on whether we're coming or going) |
| 22 |
+ |
* the list of modifiers to the ray's "newcset", which will then |
| 23 |
+ |
* take over for "clipset" on penetration. Any surface modifier |
| 24 |
+ |
* names found in "clipset" will be treated as invisible in raycont(). |
| 25 |
+ |
* |
| 26 |
+ |
* In the more complicated case of a non-void material as the |
| 27 |
+ |
* first argument, we have to backtrack up the ray tree to count |
| 28 |
+ |
* the number of times we've penetrated the front side of one of |
| 29 |
+ |
* the surfaces we care about. This relies on outward-facing |
| 30 |
+ |
* surface normals and closed objects, so is somewhat error-prone. |
| 31 |
|
*/ |
| 32 |
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|
| 33 |
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|
