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ReadGeo

Imports geometry from a specified location. The geometry is identified by the file name, which may just be a string interpreted by one of the reader implementations and not an actual file on the disk. You can read in:

• OBJ files

• FBX files containing meshes (or NURBS curves/patch surfaces converted to meshes) or point clouds. The mesh's vertices, normals, UVs, and vertex colors are read on a per frame basis or at the first frame. Materials or textures are not read in.

• Alembic (.abc) files containing meshes (or NURBS curves/patch surfaces converted to meshes) or point clouds. The mesh's vertices, normals, UVs, and vertex colors are read on a per frame basis or at the first frame. Materials or textures are not read in. For more information on Alembic, see http://code.google.com/p/alembic/.

ClosedInputs and Controls

Connection Type

Connection Name

Function

Input

img

The texture to project on to the imported geometry.

Control (UI)

Knob (Scripting)

Default Value

Function

ReadGeo Tab

file

file

none

Enter the file path and file name or use the folder icon to browse to the required location.

cache locally

cacheLocal

auto

Sets the localization attributes for the read files. Copies of the files are stored in the local folder specified in Preferences > Localisation > localisationcache for faster access times:

• always - always cache the files associated with this ReadGeo node, even if other files aren’t localized.

• auto - cache the files associated with this ReadGeo node as long as they’re located in the directory specified in Preferences > Localisation > autolocalise, otherwise they’re not cached.

• never - caching is never allowed for files associated with this ReadGeo node.

abc Options - These controls are only shown if you have imported an .abc file.

read on each frame

read_on_each_frame

enabled

When enabled, ReadGeo bakes each object's transform into the mesh points and preserves the animation.

This should be enabled for animated objects.

sub frame

sub_frame

enabled

When enabled, objects are read on sub frames.

This should be enabled for rendering motion blur, and disabled for faster UI interactions.

lock frame

lock_frame

1

When read on each frame is disabled, the object is read at this frame.

frame rate

frame_rate

24

The frame rate (frames per second) to use to sample the animation.

render points as

point_render_mode

point clouds

Determines how point primitives are rendered:

• point clouds - Render primitives as Nuke point clouds.

• particles - Render primitives as Nuke particles.

use geometry colors

use_geometry_colors

disabled

When enabled, apply geometry color attributes read from .abc files and apply them to the Nuke geometry.

NOTE:  When disabled, this control can cause differences in rendered output when compared to previous versions of Nuke. If this occurs, enable use geometry colors in the ReadGeo properties panel.

fbx Options - These controls are only shown if you have imported an .fbx file.

animation stack

fbx_take_name

-------

The take you want to use from the FBX file. FBX files support multiple takes in one file. Usually, one of the takes is a default take with no animation.

node name

fbx_node_name

-------

The mesh node you want to import from the .fbx file.

Point cloud nodes are not listed.

frame rate

frame_rate

24

The frame rate (frames per second) to use to sample the animation curves. To use this rate rather than the one defined in the FBX file, check use frame rate.

use frame rate

use_frame_rate

disabled

When enabled, the frame rate defined above is used to sample the animation curves.

When disabled, the frame rate defined in the FBX file is used to sample the animation curves.

object type

object_type

Mesh

Select the object type:

• Mesh - Import a single mesh or all the meshes (or NURBS curves/patch surfaces converted to meshes) from the FBX file.

• Point Cloud - Import a point cloud from the FBX file.

all objects

all_objects

disabled

When enabled, ReadGeo imports all the meshes in the FBX file rather than just one. This overrides whatever you have selected under node name.

read on each frame

read_on_each_frame

enabled

When enabled, ReadGeo bakes each object's transform into the mesh points and preserves the animation.

This should be enabled for animated objects.

read transform from file

read_from_file

enabled

When enabled, transform properties are imported from the FBX file and, while you can view them and use them in expressions, you cannot modify them. Whenever you reload the script, the transform properties are re-read from the FBX file to ensure they match the file content.

When disabled, you can modify the transform properties imported from the FBX file using the transform controls, and your changes are kept even if the script is reloaded.

Note that geometry data is always read from the FBX file.

obj Options - These controls are only shown if you have imported an .obj file.

update mode

update_mode

all

Sets the update mode for the OBJ geometry:

• all - loads all geometry groups for each frame.

• point-cloud - loads only point and point attributes group data at each frame. The primitives frame control specifies which frame in the sequence contains the primitive and vertex attribute group data.

primitives frame

full_geometry_frame

1

When update mode is set to point-cloud, sets which frame in the sequence contains the primitive and vertex attribute group data.

read texture w coord

read_texture_w_coord

enabled

When enabled, w coordinates are read along with uv coordinates, where present.

TIP:  Occasionally, w values contain garbage, so you may want to disable this control to use a value of 1 instead.

reload

reload

N/A

Click to reload the geometry from disk, overwriting any changes.

display

display

textured

Adjust the display characteristics of the object. These settings don’t affect the render output of the scene; these are for display purposes only in the 3D Viewer.

• off - hides the 3D geometry object.

• wireframe - displays only the outlines of the object’s geometry.

• solid - displays all geometry with a solid color.

• solid+wireframe - displays the geometry as solid color with the object’s geometry outlines.

• textured - displays only the surface texture.

• textured+wireframe - displays the wireframe plus the surface texture.

selectable

selectable

enabled

When enabled, you can make selections as normal in the Viewer. When disabled, points cannot be selected or changed.

render

render_mode

textured

Sets how the object will render. This control is independent from the display selection, but has the same settings.

cast shadow

cast_shadow

enabled

When enabled, the object can cast shadows.

receive shadow

receive_shadow

enabled

When enabled, and a material shader has been added to the geometry, the object can receive shadows.

frame range

frame_first

1

Sets the start frame for the frame range displayed in the Viewer when the Timeline range is set to Input. This can be used to display the offset used in the TimeOffset node.

frame_last

1

Sets the end frame for the frame range displayed in the Viewer when the Timeline range is set to Input. This can be used to display the offset used in the TimeOffset node.

file_menu

N/A

Select to import or export a channel file:

• Import chan file - import a channel file and transform the object according to the transformation data in the channel file. Channel files contain a set of Cartesian coordinates for every frame of animation in a given shot. You can create and export them using Nuke or 3D tracking software, such as 3D-Equalizer, Maya, or Boujou.

• Export chan file - export the translation parameters that you’ve applied to the object as a channel file. This is a useful method of sharing setups between artists.

snap_menu

N/A

• Match selection position - the object is snapped to a new position depending on the points selected.

• Match selection position, orientation - the object is snapped to a new position and orientation depending on the points selected.

• Match selection position, orientation, size - the object is snapped to a new position, orientation, and size depending on the points selected.

transform order

xform_order

SRT

Sets the operation order for scale (S), rotation (R), and translation (T). The possible operation combinations are SRT, STR, RST, RTS, TSR, TRS.

rotation order

rot_order

ZXY

Sets the order of rotation. The possible axial combinations are ZXY, XYZ, XZY, YXZ, YZX, ZXY, ZYX.

translate

translate

0, 0, 0

Lets you translate the object along the x, y, and z axes. You can also adjust translate values by clicking and dragging the object in the 3D Viewer.

rotate

rotate

0, 0, 0

Lets you rotate the object around the x, y, and z axes. you can adjust rotate values by holding down Ctrl/Cmd and dragging in the 3D Viewer.

scale

scaling

1, 1, 1

Lets you scale the object on the x, y, and z axes.

uniform scale

uniform_scale

1

Lets you scale the object simultaneously on the x, y, and z axes.

skew

skew

0, 0, 0

Lets you skew the object on the x, y, and z axes.

pivot

pivot

0, 0, 0

When you make changes to a 3D object’s position, scaling, skewing, and rotation, these occur from the location of the object’s origin point or pivot. The pivot x, y, and z controls allow you to offset the pivot point and move it anywhere you like - you can even move it outside of the object. Subsequent transformations applied will then occur relative to the new pivot point location.

You can also hold down Ctrl/Cmd+Alt and drag the pivot point to a new location in the 3D Viewer.

Local Matrix

specify matrix

useMatrix

N/A

Enable this to specify matrix values for the object you’re transforming as an alternative to setting transform, scale, skew and pivot values above.

matrix

matrix

N/A

The matrix displays values from the object’s transform, rotate, scale, skew, and pivot controls.

Check specify matrix and copy or drag-and-drop matrix values from another object to apply those values, for example, if you wanted to align objects in a scene.

Scenegraph Tab - This tab is only shown if you have imported an .abc file.

scene view

scene_view

N/A

Displays the mesh nodes in the scene. The point cloud nodes are not listed.

By default, only meshes imported into this ReadGeo node are shown. To view all meshes that exist in the Alembic file, enable view entire scenegraph.

The icons on the right indicate the state of each item in the list:

• A blank space - The item isn’t loaded into this ReadGeo node.

• A yellow circle - The item is loaded into this ReadGeo node, and is a parent item. This icon turns orange if you select the item in the list.

• A yellow bar - The item is loaded into this ReadGeo node, and is a child of a parent item somewhere further up the tree. This icon turns orange if you select the item in the list.

view entire scenegraph

all_objects

disabled

When disabled, only meshes imported into this ReadGeo node are shown.

When enabled, all meshes that exist in the Alembic file are displayed. This allows you to add to or remove from the imported items list by clicking on the icons on the right. Alternatively, you can choose Select or Deselect from the right-click menu.

To select or deselect multiple items, press Ctrl/Cmd or Shift while clicking them.
ClosedStep-by-Step Guides

Importing Geometry from OBJ Files

Importing Geometry and Point Clouds from FBX Files

Importing Geometry and Point Clouds from Alembic Files

ClosedVideo Tutorials
Closed3D Workspace Overview - Step Up to Nuke Tutorial 11

3D Workspace Overview - Step Up to Nuke Tutorial 11 from The Foundry on Vimeo.

ClosedTranscription

Nuke is not limited to a 2D space, in fact, it has a complete 3D environment built right in. For example, here is a 3D ship and a 3D sphere. In order to see the 3D environment, go to the View menu where it says 2D and switch that to 3D, and there’s the environment. In order to change the view, which is the default camera, you can use the Alt or your Option key, along with your mouse buttons. For example, Alt and left mouse button scrolls, Alt and middle mouse button zooms, and Alt and right mouse button orbits.

Let’s see what we have in the scene. There is a 3D Camera, a Spotlight, a Point light, a primitive Sphere, an imported spaceship, and a large primitive Card in the background. Let’s take a look at the node network, and you can see what we need to make a 3D scene happen. The node with the most connections is the Scene node. The Scene node groups together lights and geometry in order to pass them on to a render node. In order to render the scene so it becomes 2D, you need to have some sort of render node. In this case, there is a ScanlineRender node. Connected to the ScanlineRender is a 3D Camera. Connected to the Scene node are two lights - there is the Spotlight and the Point light. If I open up the properties on the Spotlight, you can see common options like color and intensity and, in the case of the Spotlight, cone angle. There are also two pieces of primitive geometry here - there is the Sphere and the Card. This will be a good time to note that 3D nodes have a rounded, pill-like shape, as opposed to the rectangular 2D nodes.

You can create a light or a primitive piece of geometry through the 3D menu. You can make your Point or your Spot, plus a Direct and a few specialized lights, like the one that’s called Light, which you can use to import lights from other programs, like Maya. There is also the Geometry menu, which has the primitives such as Card, or other shapes, like Cube and Cylinder. You can transform lights and geometry. For example, if I open up the Sphere, you will see there is a translate, rotate, and scale property. Once this is open, you will also see there is a transform handle. If you click+drag the handle along the axis, you can move it in that direction, for example, Y. Of course, you can also enter values into the properties panel. Lights also have their own set of transforms. Now, one new feature is the fact that lights can cast shadows right here in the 3D environment. For example, if I go to the Spotlight and go to the Shadows tab, you will see there is a place to click on cast shadows. Let’s go back to the 2D view. You can see the shadow of the Sphere right here on the spaceship. Now, aside from shadows of course, you can animate all of these properties. You can animate the light, changing over time, as well as the geometry. There are also animation buttons beside all of these properties. You can key these as you would any other node inside Nuke.

You will notice that the two pieces of geometry have shaders connected to their img pipes. These are necessary for the surfaces to be lit correctly. The Sphere has a Phong, which is similar to the one you might have in a program like Maya. The Card has an Emission shader, which has the emissive component or the ambient color component. Now, in terms of the spaceship, it has to be imported through a ReadGeo node. ReadGeo node has a place to bring in the file, and this supports .fbx files, or .obj files, or alembic files, .abc. If there is animation in the file, Nuke will recognize it. For example, with the .fbx file, it might have multiple takes. Nuke will recognize that and you can choose the animation take. So, if I go back to the 3D view, scrub the timeline, and we will see the ship is pre-animated, and this animation was created in Maya. There is also a material connected to the img pipe of the ReadGeo. Now, because the UV texture space came through the .fbx file, in order to map the geometry, you just need to bring in the texture bitmaps through Read nodes, and connect to a shader. For example, here is the diffuse map connected through the mapD, or map diffuse. There is a specular map connected through the mapS, or map specular. Lets go back to the 2D view.

Now, if anything is animated, you can also activate motion blur. To do that, you go to the render node and, for example, with the ScanlineRender, go to the MultiSample tab and change samples to a higher number like 8. At that point, the motion blur will appear, as you can see right here. The higher the samples number, the higher the quality.

So, there is a brief introduction to Nuke’s 3D environment. Keep in mind that any node you need to create for this you can find through the 3D node menu. This includes all your shaders, geometry, lights, Scene nodes, and cameras. Aside from animating lights and geometry, you are also free to animate cameras. They have their own set of transforms. In any case, I would suggest exploring this component of Nuke.

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