Ambient Occlusion Node for Lightwave 9

---

Parameters:

• Number of rays to be shot into the scene from the currently rendered point.
  This parameter can be animated via the corresponding node input, however it is strongly recommended to use a fixed number. Otherwise render times might increase dramatically.


• Maximum scatter angle of the rays. 90° corresponds to a complete hemisphere, smaller angles lead to a smaller spherical cap. This parameter can be animated via the corresponding node input, however it is strongly recommended to use a fixed number. Otherwise render times might increase dramatically.


• Maximum range of the rays. If a ray hits a surface at a distance > range, it is treated like it hit nothing at all.
  Set this parameter to 0m for infinite rays.
  If full surface evaluation is enabled, this parameter is ignored for the color output. Rays are always infinite in this case.


• Mode:
   Ambient: Rays are shot from the current point in all directions (depending on the angle) centered around the point's normal
   Directional: Rays are shot from the current point towards the target position. Works best with very small angles.
   Inv. directional: Rays are shot from the target position towards the current point. This can give funny results, but usually you will want to use directional mode.
   Reflective: Rays are shot from the current point as if they were reflected by the surface. This is especially useful for reflection blurring effects.
   Refractive: Rays are shot from the current point as if they were refracted by the (transparent) surface. This is especially useful for refraction blurring effects.


• Target position for directional or inv. directional mode. You could plug in an item position from an item info node here.


• Refraction Index: In refractive mode this value determines the refraction index of the surface at the current position.


• Ignore transparency treats all polygons as opaque. When this option is disabled, the rendering will be significantly slower, but transparent or semitransparent
  polygons will have accordingly less influence on the occlusion value.
• Full surface evaluation: The slowest evaluation, but it should be used in reflective/refractive mode to get a correct color output from the reflected/refracted rays.
  If you want backdrop images to be visible in reflections, this parameter must be enabled.
  (Internally it uses LW's raytrace() function instead of the rayshade() or raycast() funcs)


• Ray recursion limit: Leave this at 0 unless you know what you are doing, rendertimes might increase dramatically.


• The last button will copy the current node's settings to all other nodes in the scene.


• The output value is 1-Occlusion so it can be plugged directly into the diffuse channel of the surface.

Mode: Ambient	Mode: Directional Light source (target position) is located at the center
Ignore transparency enabled The window polygon has 100% transparency but is treated as opaque	Ignore transparency disabled The window polygon has 100% transparency and is treated as such
Simple setup for reflection blurring	Simple setup for refraction blurring

Note: If you don't see any results in the rendering, make sure you have raytracing enabled in the render options.

---

Special thanks to Gerardo Estrada for his extensive tests, suggestions and patience


If you have questions, comments, bug reports, jobs : skidbladnir@web.de

---

Latest changes:

• 10 Jan 2007
  fixed a bug that caused rendering errors in transparency mode
• 13 Mar 2007
  added color output and reflective + refractive mode
• 27 Jul 2007
  fixed a bug that could cause a crash

---

27 Jul 2007

Sebastian Goetsch
Kollwitzstraße 4
10405 Berlin
Tel +493044357467
E-Mail: skidbladnir@web.de