Most of the 3D nodes are a different shape (rounded) to the Nuke-standard 2D nodes (squarish). This is to visually emphasise the fact that Nuke's 2D and 3D environments are like Photoshop's bitmap and vector tools: they live next to each other but can not naturally mix.
Geometry Sub Menu
Sphere, Cube, Cylinder
Nukes simple geometric solids.
In addition to being to make simple solids, using the Modeler Nuke can also make geometry from scratch. Maya it ain't. Its purpose is to derive simple geometry from footage. This can be used for the purposes of camera projection, simple texturing etc. is roughly how to use it:
- Feed into it one Camera obtained from a #CameraTracker (into the Camera feed) and one image sequence or movie (into the Source feed).
- Connect the Viewer arrow to the image sequence and double-click the Modeler.
- Navigate to a frame that presents a clear view of the geometry that you wish to model.
- In the Viewer window you will find three controles: Add vertices, Add faces and Edit/Select. Add four vertices to the clearest face in view.
- Connect them up one by one using the add faces button. You will se that you are now looking at a simple square.
- Navigate to a few frames further on and re-position the corners of the square so that they coincide with the new on-screen position of those points.
- You will notice that the square now has a face upon it. Scan up and down the timeline to see if this geometry is 'in sync' with the real-world object. You may edit its position but remember that every time you do, a new keyframe will be laid down.
- New faces may be laid down at will.
- You may export this geometry using a WriteGeo node. This is Nukes route to obj export. The Modeler is briefly demonstrated in this video (at around the 3.30 mark).
Lights Sub Menu
This will light the objects in the scene according to the values of an image. This is great for passing on the values of a 3D scene onto an object. A High Dynamic Range (HDR) image is recommended for this purpose. They are addressed in these Foundry tutorial.
The lights in Nuke are simple yet effective. They can even cast shadows from an object onto a surface. However they can not cast self-shadows (shadows cast from an object onto itself).
Modify Sub Menu
Glues several items of geometry together. This is useful for given them all a single material or texture.
This will displace a piece of geometry according to the values of a channel. This is good for making rough terrains or undulating water from noises.
Shader Sub Menu
Nuke can apply a material to an object, and ascribe to it specular, diffuse and emission properties. However, in order for these values to 'register' the scene must be lit with Nukes lights. A simple light / shader scene can be found in the Simple_3D_Scene_with_Materials page.
Well, a camera is a camera. No news there. Some interesting points: the Nuke camera can be used as a projector as well as a receiver of images. This is useful for camera projection. An example of its use can be found in the [[[Simple 3D Scene]] page. It can also be used to render out spherical projection of the environment that it is in. This is good for making environment maps (useful for lighting scenes in Maya). A tutorial link is here.
From the camera can also be exported a .chan file. This will contain all camera movement data and will be the bridge in the Maya to Nuke camera workflow.
A simple Nuke 3D environment can consiste of nothing more than a Card, Camera and ScanlineRender. However, this is is limited: no more than one geometry feed can be rendered at one time and it can not be lit with a light. The solution is to use a Scene node. This big, round node is invisible in both the 2D and 3D world, its function being to offer a 'home' to multiple 3D elements such as cards, 3D objects and lights and to ensure that they render out as one thing. There are practically no parameters to the Scene node. A script can contain more than one scene node. A simple scene can be found in the Simple_3D_Scene_with_Materials page.
This is the medium for the translation from 3D to 2D. It grabs information from the Camera and any Cards, Scenes, .objs etc that are connected to it and delivers a 2D render. An example of its use can be found in the Simple 3D Scene page. Though it has a lot of paramaters and tabs the only one that I have so far found myself needing is in the MultiSample tab. Here the samples and Shutter can be increased to produce motion blur on any moving object.