Card3D

The Card3D node lets you apply the same geometric transformations possible with the Transform node, but gives you an additional axis of operation, z. It transforms the image as though it was printed on a flat card and placed in front of the camera. The Card3D node’s transformations are not truly 3D, but rather what is sometimes called “2.5D” - meaning that you can move an element back on the z axis, but doing so does not convey the sense that it is behind or in front of another element. 2.5D transformations are useful for tasks like “cheating” the perspective of an element or “faking” a camera zoom.

Inputs and Controls

Connection Type

Connection Name

Function

Input

axis

An optional Axis node that works as null object to which the card can be parented. If connected, you can use the Axis transformation controls to control the Card3D node. Rotating the Axis node, for example, rotates the Card3D node. This can be useful if you want to control several nodes using the same Axis node.

cam

An optional Camera node used for viewing the card.

unnamed

The image to place on the card.

Control (UI)

Knob (Scripting)

Default Value

Function

Card3D Tab

file_menu

N/A

The File Menu lets you:

Import chan file - Import a channel file and move the card according to the transformation data in that 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 transformation data you have applied to the card as a channel file. This is a useful method of sharing setups between artists.

snap_menu

N/A

The Snap Menu lets you:

Match selection position - match the position of the card to any vertices you have selected on a 3D geometry object in the Viewer.

Match selection position, orientation - match the position and orientation of the card to any vertices you have selected on a 3D geometry object in the Viewer.

Match selection position, orientation, size - match the position, orientation, and size of the card to any vertices you have selected on a 3D geometry object in the Viewer.

To select vertices in the Viewer, you need to attach a 3D object to the Viewer and press Tab to activate the Viewer’s 3D mode. Then, click to activate the Vertex selection tool, and select vertices on the object by dragging a marquee over them.

transform order

xform_order

SRT

Select the order by which Nuke executes scales, rotations, and translations (S signifies scale, R rotation, and T translation). The order can affect the outcome.

rotation order

rot_order

ZXY

Select the order by which Nuke executes rotation on individual axes (X, Y, and Z).

translate xyz

translate

0, 0, -1

Translates the card on the x,y, and z axes.

Alternatively, you can drag on any axis on the transformation overlay in the Viewer.

rotate xyz

rotate

0, 0, 0

Rotates the card on the x, y, and z axes. This is useful for cheating the perspective.

Alternatively, you can press Ctrl/Cmd while dragging on any axis on the transformation overlay in the Viewer.

scale xyz

scaling

1, 1, 1

Scales the card on the x, y, and z axes.

Setting one of these to a negative value reverses the input image along that axis.

uniform scale

uniform_scale

1

Scales the frame simultaneously on x, y, and z. This effectively gangs the scale xyz values.

skew xyz

skew

0, 0, 0

Skews the card on the x, y, and z axes.

pivot xyz

pivot

0, 0, 0

When you make changes to the card’s position, scaling and rotation, these occur from the location of the card’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 card. Subsequent local transformations will then occur relative to the new pivot point location.

You can also position the pivot point by pressing Ctrl/Cmd+Alt while dragging in the Viewer.

Local matrix

specify matrix

useMatrix

disabled

Enable this control 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.

geometry

lens-in focal

lens_in_focal

1

The focal length of the camera that took the picture on the card. The card is scaled to the correct size so that at distance Z, the card fills this field of view.

lens-in haperture

lens_in_haperture

1

The horizontal aperture of the camera that took the picture on the card. The card is scaled to the correct size so that at distance Z, the card fills this field of view.

render params

output format

format

root.format

Select the format to which you want to output the sequence. If the format does not yet exist, you can select new to create a new format from scratch. The default setting, root.format, resizes the image to the format indicated on the Project Settings dialog box.

filter

filter

Cubic

Select the filtering algorithm to use when remapping pixels from their original positions to new positions. This allows you to avoid problems with image quality, particularly in high contrast areas of the frame (where highly aliased, or jaggy, edges may appear if pixels are not filtered and retain their original values).

Impulse - remapped pixels carry their original values.

Cubic - remapped pixels receive some smoothing.

Keys - remapped pixels receive some smoothing, plus minor sharpening (as shown by the negative -y portions of the curve).

Simon - remapped pixels receive some smoothing, plus medium sharpening (as shown by the negative -y portions of the curve).

Rifman - remapped pixels receive some smoothing, plus significant sharpening (as shown by the negative -y portions of the curve).

Mitchell - remapped pixels receive some smoothing, plus blurring to hide pixelation.

Parzen - remapped pixels receive the greatest smoothing of all filters.

Notch - remapped pixels receive flat smoothing (which tends to hide moire patterns).

Lanczos4, Lanczos6, and Sinc4 - remapped pixels receive sharpening which can be useful for scaling down. Lanczos4 provides the least sharpening and Sinc4 the most.

clamp

clamp

disabled

When using filters that employ sharpening, such as Rifman and Lanczos, you may see a haloing effect. If necessary, check clamp to correct this problem.

black outside

black_outside

enabled

This renders as black pixels outside the image boundary, making it easier to layer the element over another. If you uncheck this control, the outside area is filled with the outermost pixels of the image sequence.

In most cases, you should keep black outside checked. However, you may want to turn this off for camera shake, or if you want to texture-map or intersect the output with a similar shape.

Note:  Enabling black outside also adds a solid alpha covering the input image area if no alpha is present.

motionblur

motionblur

0

Sets the number of motion blur samples. A value of 1 should produce reasonable results for most sequences.

Increase the value to produce more samples for higher quality, or decrease it to shorten the processing time. The higher the value, the smoother the result.

shutter

shutter

0.5

Enter the number of frames the shutter stays open when motion blurring. For example, a value of 0.5 corresponds to half a frame. Increasing the value produces more blur, and decreasing the value less.

shutter offset

shutteroffset

start

This value controls how the shutter behaves with respect to the current frame value. It has four options:

centred - center the shutter around the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 29,5 to 30,5.

start - open the shutter at the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 30 to 31.

end - close the shutter at the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 29 to 30.

custom - open the shutter at the time you specify. In the field next to the dropdown menu, enter a value (in frames) you want to add to the current frame. To open the shutter before the current frame, enter a negative value. For example, a value of - 0.5 would open the shutter half a frame before the current frame.

shuttercustomoffset

0

If the shutter offset control is set to custom, this field is used to set the time that the shutter opens by adding it to the current frame. Values are in frames, so -0.5 would open the shutter half a frame before the current frame.

Step-by-Step Guides

Applying Core Transformations in 2.5D