SoVolumeRenderingQualitylighting Property |
Enable gradient based lighting (computed on the GPU).
Namespace: OIV.VolumeViz.Nodes
Default is false. Gradient based lighting is computed using the direction and magnitude of gradient vectors computed from the data values in place of "normal vectors" in the lighting equation. A gradient vector is computed for each sample point along the rays cast through the volume.
VolumeViz also supports screen space lighting (see the OIV.VolumeViz.Nodes.SoVolumeRenderingQuality.deferredLighting field).
Notes:
The result of the gradient lighting computation is affected by how the gradient vectors are computed. See the OIV.VolumeViz.Nodes.SoVolumeRenderingQuality.gradientQuality field.
Gradient lighting may produce "noisy" results when the gradient magnitudes are small and/or the gradient directions are not consistent. This often happens, for example, in relatively homogeneous regions of a volume. Several fields are provided to compensate for this effect. See OIV.VolumeViz.Nodes.SoVolumeRenderingQuality.gradientThreshold and OIV.VolumeViz.Nodes.SoVolumeRenderingQuality.surfaceScalarExponent.
Both gradient lighting and deferred lighting may be enabled at the same time, but the intent is that the application should use one or the other.
In any case, do not use the OIV.VolumeViz.Nodes.SoVolumeRender.lighting field.
LIMITATIONS
Only directional lights (OIV.Inventor.Nodes.SoDirectionalLight) are supported.
Only one light source, the first one traversed in the scene graph, is supported.