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Creating a Pipeline

  1. Start MotionSampler by typing: 
    ms3

    
or by click-dragging down the Utilities menu in Alias until you get to MotionSampler and then releasing the mouse button.
    

    
A red outline appears attached to the cursor.
  2. Drag the outline to the where you want MotionSampler to be. Click the left mouse button. The MotionSampler window appears.
  3. Select File Retrieve Model. A File Browser appears.
  4. Use the File Browser to retrieve the Tutorial1.wire file. This file contains a sphere and a cube. These objects are tessellated into polygons and displayed.
  5. Select Scene View Scene or click on the following button to switch to a single view:

Adjusting the View

  1. Try to make the view similar to the view below so that it is not as orthogonal as the original view. To change the view, use either:

  2. Select Display Grid Options....

    The following window opens:

  3. Click the button beside Solid to create a solid, tiled floor and then click the Done button.
  4. Use the Floor button to move the floor up until it just meets the bottom of the sphere and cube.

    The Floor button appears as follows:

    You can tell when you have the floor in the right position because it will intersect the cube and sphere as follows:

Creating the Pipeline

This section of the tutorial shows you how to create a pipeline to control the X and Z position of the sphere with the mouse. A DAG sink, a Mouse source, a FloatJoin (to join three float parameters into a vector) and a couple of Offset modules are needed to scale the mouse coordinates correctly.

  1. Click the Pipeline button, which appears as follows:

    The MotionSampler window changes to appear as follows:

  2. Double-click the DAG module under the Sink Modules list at the bottom left of the Plug-in Module Library.

    A module tile called DAG appears in the upper left corner of the View/Edit area.

  3. Double-click the following modules to select them:

  • Move each tile by clicking with the cursor on the module's name label and dragging it to arrange the modules as shown below:

    Editing the DAG Sink Module

    The DAG sink module must have a related wire file. The sink module's name should be matched with the name of a dag node.

    1. Click the down arrow on the DAG module to display the menu as follows:

    2. Drag down until Rename... is highlighted and release the mouse button. The Rename Module window appears.

    3. Type sphere in the edit field to rename the sink module to the name of the node in the wire file.

    Connecting the Modules

    To connect the modules to each other and form a pipeline:

    1. Click-drag from the X outlet of the Mouse module to the F inlet of one of the Offset filters, and from the Y outlet to the F inlet of the other Offset.
    2. Connect the F outlet of the first Offset filter to the X inlet of the FloatJoin, and connect the other Offset filter's F outlet to the Z inlet of the FloatJoin.
    3. Connect the X outlet of the FloatJoin filter to the T (or translation) inlet of the DAG sphere sink.

    Your pipeline should appear as follows:

    Calibrating Mouse Motion

    The next step is to scale the motion coming from the Mouse source to match the wire file more appropriately.

    The Mouse source reports actual cursor position, so if you have a 1280x1024 monitor, these positions have a large range. The Offset modules are used to change this scaling.

    1. Select Edit from the first Offset filter's menu.

      The Module Text Editor appears displaying the Offset's parameters as follows:

    2. Change the scaling parameter to 0.01. This defines a reasonable range of motion without sending the sphere flying out of the view.

    If you are having trouble generating this pipeline, it has been stored as Tutorial1.pipe. You can load the stored pipeline by selecting Pipeline Retrieve Pipeline from the menu bar, and selecting Tutorial1.pipe from the File Browser. Retrieving the stored pipeline also clears out the pipeline you have been working on.

  • Click the OK button to close the Module Text Editor and apply the changes to the Offset module.
  • Make the same changes to the other Offset module.

    Sampling Motion

    1. Return to the single view window by clicking on the single view icon on the left side above the viewing area.
    2. Click the Sample button to place the system in live standby mode.

  • Move the mouse around and observe the sphere.

    As you move the mouse and the position of the sphere changes, you may need to zoom your view out to see it.

  • Exit sampling mode by pressing the F1 key.

    Because the mouse is defined as the motion capture device, it is inconvenient to click the Sample button each time you want to enter or leave sampling.

    The F1 key is the keyboard shortcut to toggle sampling on and off.

  • Use the view control buttons to change the view.
  • Press the F1 key if you want to start sampling the mouse's motion again.

    Recording and Playing Back Motion Data - Using the Shuttle Bank

    You have now done live motion sampling with MotionSampler. Next, you will record data and see how it can be played back, and how animation can be overlaid with previous work.

    The Shuttle Bank is like a VCR, with controls for forward, reverse, and stop. The knob in the slider above the VCR controls can be dragged.

    As you play forward or reverse, or as you drag the knob, the time displayed in the Current box changes. MotionSampler's current time settings are contained in the Shuttle Bank.

    1. Stop Sample mode either by clicking the Sample button, or by pressing the F1 key.
    2. Move to the beginning of the frame range by click-dragging the slider, by clicking in the Current edit field and entering 0, or by clicking the following button:

  • Press the F1 key return to Sample mode.
  • Press the F2 key to place the system in Record mode. The shuttle begins to move forward.
  • Move the mouse around for a second or two.
  • Press the F2 key again to stop Record mode.
  • Press F1 to stop Sample mode.
  • Return the shuttle back to frame 0 as in step 2 above.
  • Click the following button on the Shuttle Bank:

    The animation of the previous movements of the mouse are replayed.

    10. Press the following button to stop the playback:

    You can adjust the view with the view controls while playing back the animation.

    11. Select Playback Use Min/Max to set the shuttle's Start and End frames to be the duration of the animation.

    12. Select Oscillate in the Play menu next to the shuttle controls as follows:

    Now when you start playback, the animation replays continuously, first forward, then in reverse, and so on.

    You can also select Loop to replay the animation continuously forward.

    Recording onto Existing Animations

    You can record additional motion on top of this original animation.

    1. Stop the playback and click the following button to switch back to the Pipeline Editor:

    2. Select Rename from the DAG module's menu.
    3. Type cube instead of sphere to move the cube rather than the sphere.
    4. Return to View mode by clicking the following button:

  • Return to Sample mode by pressing F1. Now the motion of the mouse moves the cube instead of the sphere.
  • Press the F1 key to stop Sample mode.
  • Reset the shuttle to frame zero.
  • Press the F1 key to start Sample mode.
  • Press the F2 key to start Record mode.

    10. Move the mouse around.

    The sphere motion previously captured moves the sphere at the same time as you are moving the cube.

    11. Exit Record mode by pressing the F2 key and exit Sample mode by pressing the F1 key.

    12. Reset the shuttle to frame 0 and play back the result. Both the motion on the cube and sphere play back, with motion recorded separately on each.


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