Test Object

Usage  |  Controls

The Test Object node can be used to insert a geometric model into the scene to test the quality of the camera track. Any OBJ, FBX or Alembic file can be used, and PFTrack comes with a small number of sample objects included.

Test objects can be keyed against a blue or green screen, and a stereo anaglyph can also be generated for stereo camera pairs. The test object node can have multiple inputs (each containing a camera).

Usage

Test Objects that are available to be inserted into the scene are listed in Available objects. Additional objects can be added from OBJ, FBX or Alembic files.

Objects will also be loaded automatically from the user's Documents directory at objects (the location of this directory can be changed in the preferences window)

By default when an object is inserted into the scene it is scaled to unit size and its origin relocated to be at its centre. However, both of these can be controlled by the relevant tick-boxes.

Objects present in the scene are detailed in the Scene Objects list. Select an object to interact with it. Interaction modes allow the object to be positioned, rotated and scaled.

Each object inserted into the scene also has a relative scale factor displayed in the Scene Objects list. This value defaults to 1.0 and will change as the object is scaled using the scale manipulator. This can be used to help assess the relative scales of test objects at different locations in the frame when positioning objects in a third-party application.

Controls

Available objects

Re-scale: When enabled, an object is re-scaled to unit size when added to the scene.

Re-centre: When enabled, an object is re-centred to its middle when added to the scene.

Import: Display a file browser allowing additional OBJ, FBX or Alembic objects to be imported.

Remove: Remove the selected object from the list of available objects.

Add to scene: Add the selected object to the scene. Objects can also be added by double clicking on their entry in the list.

Scene objects

Interaction mode: Select the interaction mode for the selected scene object. Options are:

- Place at selected feature: Position the object at the tracker identified by left clicking in the Cinema window.

- Fly: Rotate and translate the object relative to the camera. Holding the Alt/Option key and clicking and dragging with the left mouse button will rotate the object. Using the right mouse button will translate the object in the camera plane, and the middle mouse button will move the object further or closer to the camera (Note: the middle mouse button will not change the scale of the object).

- Translate, Rotate, Scale: Translate, rotate or scale the object using manipulators.

- Set Origin: Choose an object vertex to become the object's origin point. This allows to control the centre of rotation and scale and provides finer control over the object positioning when Positioning mode is Origin.

Positioning mode: This menu is used to select the positioning mode when using the Place at selected feature interaction mode. Options are:

- Origin: Position the object's origin at the selected feature.

- Y-min: Position the object above the selected feature.

- Y-max: Position the object below the selected feature.

Coordinate system: This menu is used to specify the coordinate system of the original object that has been imported.

Duplicate: Duplicate the selected scene object.

Delete: Delete the selected scene object from the scene.

Colour keyer

The colour keyer can be enabled to help visualise test objects for green or blue-screen shots. The key obtained from a blue or green-screen shot can be visualised by enabling the alpha channel in the Cinema window.

Channel: The blue or green channel to key from. Auto will attempt to estimate whether a blue or green screen is being used.

Gain: The scale of the initial alpha values before adjusting for the black or white-points.

Black point: The alpha value obtained from the blue or green screen image that will be mapped to black in the key

White point: The alpha value obtained from the blue or green screen image that will be mapped to white in the key. If the key contains mid-range alpha values pixels covered by the green or blue screen, they can often be removed by decreasing the white-point parameter.

Enable: When enabled, the keyer will mask the rendering of test objects by the key. Note that the colour keyer can only be enabled on platforms that support GPU rendering.

Stereo

When cameras have been attached to two inputs, a stereo anaglyph of the background image and test objects can be rendered and viewed using coloured glasses. The anaglyph menu can be used to choose between a red/cyan or a blue/yellow anaglyph.

Display

Render style: Controls how the test object is rendered.

Show trackers: When enabled, trackers will be displayed in the Cinema window.

Show ground: When enabled, the ground plane will be displayed in the Cinema window.

Show horizon: When enabled, the horizon line will be displayed in the Cinema window.

Show bounds: When enabled, the bounding box of moving tracker groups will be displayed.

Show paths: When enabled, the path of moving tracker groups will be displayed

Bake objects: When enabled, objects will be rendered directly into the copy of the background image stored in memory, rather than as an overlay in the Cinema window. This allows the raster data and test objects to be exported as a clip by an Export node. Note that when either the keyer or the stereo anaglyph are enabled, objects are always baked into the background image.

Darken footage: When baking objects darken the background footage so that the overlays such as objects and trackers are more readily visible.

Default Keyboard Shortcuts

Keyboard shortcuts can be customised in the Preferences.

Add To Scene	Shift+A
Place at selected feature	Shift+P
Fly	Shift+F
Translate	Shift+T
Rotate	Shift+R
Scale	Shift+S
Duplicate	Shift+D
Delete	Del
Enable Keyer	Shift+K
Show Trackers	Ctrl+T
Show Ground	Ctrl+G
Show Horizon	Ctrl+H
Show Bounds	Ctrl+B
Show Paths	Ctrl+P
Bake Objects	Ctrl+K
Darken Footage	Ctrl+D
Next Clip	C