Description
This node is designed to compute a dynamic transformation matrix to modify the position of a 3D object in your 3D scene in sync with it’s real life counterpart in the real life scene.
It was originally designed to work with the Kinemotion tracking system (as well as third party tracking systems such as Blacktrax) but this functionality has since been directly built-in to the Kinemotion panel for users using the Kinemotion tracking kit. It can still be used with other third-party tracking systems.
Additional ressources can be found on this tutorial page.
Properties
General
Click on the Add Point button to add points into the table. You need a minimum of 3 points to compute a transformation matrix.
For each point, set the local coordinates for each tracking led, which will be the distance between the center of your object and the physical position of each leds (in real life).
You can choose to select the tracking leds either by Id or by tag (for Blacktrax systems)
Minimum Points: Set the minimum number of points required for a transformation to be valid. If the number of points detected is below this value, the transformation will be flagged as invalid (e.g. FALSE on its Valid output)
Default : 3
Error allowed: Sets the tolerance for each tracking led. Higher values accept more error in the tracking position. Lower values require a very precise measurment for the tracking led’s position to be considered valid.
Default : 2.0
Reject bad points: Toggle to drop/ignore tracking leds for which the error is higher than the allowed value.
Default : ON
Filter
Enable Filter: Toggle to enable a filter to smooth the movement applied by the transformation matrix. This is done by applying algorithms to guess the position of the object in between frames.
Default : ON
Auto dt: Toggle to activate an automatic computation of the delta time between two frames of measurement by the tracking system.
Default : OFF
dt (s): Manually set the delta time between two frames of measurement by the tracking system.
Default : 0.008
delay (s): Manually set a value to compensate for the delay in displaying the output image in the video projector system.
Default : 0.0
Filter Method: Set the algorithm to use for filtering. Choices are : Median or Kalman
Default : Median
Alpha: Only active whenFilter Methodis set to Median.
Default : 0.99
Inputs
| Name | Type | Description |
|---|---|---|
| Array | Array | Array on which to apply the transform |
Outputs
| Name | Type | Description |
|---|---|---|
| Transform | Matrix4×4 | Displays the values of the transformation matrix |
| X | Float | Outputs the X position to the 3D object |
| Y | Float | Outputs the Y position to the 3D object |
| Z | Float | Outputs the Z position to the 3D object |
| Sx | Float | Outputs the X scale to the 3D object |
| Sy | Float | Outputs the Y scale to the 3D object |
| Sz | Float | Outputs the Z scale to the 3D object |
| RotX | Float | Outputs the X rotation to the 3D object |
| RotY | Float | Outputs the Y rotation to the 3D object |
| RotZ | Float | Outputs the Z rotation to the 3D object |
| Valid | boolean | True if the transformation matrix is active and being applied. False if it is not. |
Example
For a use case of this node, check this tutorial page.
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