Upgrading from Eddy 2

Eddy for Nuke 3.0 has a new rendering core, and as a result many of the rendering nodes have been changed or updated. This page describes the main changes needed in order to upgrade an Eddy 2 scene to an Eddy 3 scene.

E_Shader replaced by E_RenderableVolume

The old E_Shader node in Eddy 2, used to define a volume to be rendered, has now been replaced by the E_RenderableVolume node in Eddy 3. There are more material types available in Eddy 3 but the settings are generally the same as in Eddy 2.

Note

There is still a E_Shader node in Eddy 3, however this is different to the old Eddy 2 node. It is now a node for creating general purpose shader networks and on its own does not define a volume to be rendered.

E_Render changes

There are many new settings for the renderer in Eddy 3, but these are the most important changes:

  • The ‘maximum progressions’ setting has been replaced with a ‘maximum samples’ setting. When converting this the old value should be divided by 20. This is because in the new renderer the ‘maximum samples’ setting is the number of camera ray samples, and the number of volume samples to take for each camera ray is a separate setting under the advanced tab. The default number of volume samples for each camera ray is 20, which is why the old value should be divided by 20.

  • The ‘multiple scattering’ setting has been replaced by the ‘maximum ray depth’ setting. To disable multiple scattering, the maximum ray depth should be 1. To enable multiple scattering, set the maximum ray depth to a larger value, e.g. 10.

  • The method for measuring the error in adaptive sampling has been improved, so the ‘error bound’ setting may need to re-adjusted if it had been previously modified.

E_Holdout removed

The E_Holdout node has been removed, as now a holdout is just a mesh with a special material. Use the E_RenderableMesh node, and set it to use the ‘Holdout’ material. The ‘primary visible’ flag on E_Holdout can be replaced by setting the ‘camera’ visibility flag on the E_RenderableMesh.

Light changes

  • Quad area lights were previously two-sided, they are now single-sided by default in Eddy 3. Either the ‘two-sided’ flag on the light can be set, or the orientation checked to make sure it is correct (the viewer will show the emitting side of the light as white, the non-emitting side as black).

  • Environment lights are now rendered in the image by default. To disable this, uncheck the ‘Camera’ visibility flag on the light.

AOV changes

  • The E_RenderAOV node has changed significantly. There is now a much larger selection of predefined output types to choose from, although the old types all have new equivalent types. The clamp settings have been removed, improved versions of these are now found on the E_Render node advanced settings.

  • The ‘light tag filter’ on the E_RenderAOV node now supports just a simple list of light tags that should be included in the AOV. More complicated combinations of light tags can now be implemented using light path expressions.

  • E_LightGroup has been replaced by E_RenderableGroup, as any renderable object can now be tagged, not only lights.

Implicit volume rendering

The ‘minimum feature size’ setting on the old E_Shader node, used to define a step size for raymarching, has been removed. Now in order to specify a raymarch step size for an implicit volume, the custom volume settings contain a new parameter ‘Raymarch step size override’. If there are multiple implicit volumes in the scene then each volume can specify its own independent step size.