author Florian Link
package MeVisLab/Standard
dll SoPathTracer
definition SoPathTracer.def


The SoPathTracerMesh module allows to render triangle meshes in a SoPathTracer. It supports opaque and transparent meshes and offers correct integration/blending with the rest of the scene. Transparent meshes are much slower than opaque meshes, since the rays need to traverse the complete mesh when triangles are transparent.

The inMeshScene can contain any number of SoPathTracerMaterial nodes. A SoPathTracerMaterial affects all meshes that are behind it in the Open Inventor scene. This allows fast update of material properties without full mesh recreation, by setting Mesh Update Mode to UpdateColors.

The meshes are gathered from the inMeshScene. The meshes are converted to a BVH (bounding volume hierarchy) to allow fast ray tracing on the GPU.

Texturing is not yet implemented.


In this rendering, meshes are used for rendering the liver segments and the vessels. Note the usage of a clipping plane and the possibility to enable/disable clipping on individual meshes.


Default Panel


Input Fields


name: inMeshScene, type: SoNode

The input scene that is scanned for triangle meshes.

Parameter Fields

Field Index

Enable Clipping: Bool
Enabled: Bool
Flip Clipping: Bool
Mesh Update Mode: Enum
Update Meshes: Trigger

Visible Fields


name: enabled, type: Bool, default: TRUE

Enables the rendering.

Mesh Update Mode

name: meshUpdateMode, type: Enum, default: AutoUpdateColors

Selects the update mode.


Title Name Description
Off Off The meshes are only update when Update Meshes is pressed.
Auto Update Colors AutoUpdateColors Auto updates the scene when only colors/transparency of materials have changed, otherwise no update.
Auto Update All AutoUpdateAll Updates the meshes on each change of the input scene.

Update Meshes

name: updateMeshes, type: Trigger

Updates the meshes from the input scene.

Enable Clipping

name: enableClipping, type: Bool, default: TRUE

If enabled, Open Inventor clipping planes affect the mesh rendering.

Flip Clipping

name: flipClipping, type: Bool, default: FALSE

If enabled, the Open Inventor clipping planes are flipped before being applied to the mesh.