Creating a coordinate system
 
 
 

MatchMover manages a set of user-defined coordinate systems with respect to the cameras and 3D points in the Workspace. If no coordinate system is specified, MatchMover chooses an arbitrary one. You can define a coordinate system in order to facilitate the manipulation of your exported project in a 3D package. If no point relations have been set up, MatchMover aligns the coordinate system on the computed position of the camera for the first frame; the default is the camera looking towards Z and Y as Up axis, but this changes according to your project's 3D parameters if you selected a different up axis.

NoteYou can bypass this section of the lesson by openningShot_coordsys.mmf. This file can be found in the Tutorials/Supervised_Shotdirectory. You can then proceed to Add a 3D object.

Open the file for the lesson

To ensure this lesson works as described, do the following:

  1. Ensure that it is set to Full mode.

    To set MatchMover to Full mode, select Full from the MatchMover toolbar.

  2. Ensure that MatchMover is set to 3D mode.

    To switch MatchMover to 3D mode, click the 3D space icon that is located in the top left of the Workspace view. If a 2D space icon appears instead, then MatchMover is already in 3D mode.

  3. If you have not already done so, copy the Tutorial folder from its installation location to your a project directory.
  4. Open the scene file named Shot_solved.mmf. This file is in the Tutorials directory that you copied from the MatchMover installation directory to a local directory: Tutorials\Supervised_Shot\Shot_solved.mmf.

Setting up the coordinate system

To set up the coordinate system

  1. In the Project window, right-click the Coordinate Systems folder and select New Coordinate System from the pop-up menu.

    A grid and coordinate indicators appear in the Workspace.

  2. In the Parameters window, click the Coord 01 tab.

    For your new coordinate system values, you will use Track 05 as the origin. This point is the center of the grid and floor of the scene.

  3. In the General section, select Track 05 from the Origin list.

  4. To set the grid value, in the General section, do the following:
    • In the Distance field, type 20.00.

      This value defines the distance between two points in the scene.

    • From the From list, select Track 07.
    • From the To list, select Track 09.

    These two points provide tracking locations in the corners of the room, making them well suited for defining the boundaries of the coordinate system.

  5. Click the Axis 1 tab and do the following:
    • Select Y from the X, Y, and Z list.
    • Select normal to 3 points from the list to the right of Y.
    • For the three points, select Track 03, Track 04, and Track 05 from the lists located under Y.

    These settings create a Y-based coordinate system using three points that are located on the ground of the scene.

  6. Click the Axis 2 tab and do the following:
    • Select Z from the X, Y, and Z list.
    • Select through 2 points from the list to the right of Z.
    • For the two points, select Track 01 and Track 02 from the lists located under Z.

    These settings create a Z-axis as the second axis which is based on the crosses on the wall of the scene background.

  7. Click Apply Coordinate System to validate your coordinate settings.

    The defined coordinate system appears in the Workspace.

Add a 3D object

Now that you have defined a 3D coordinate system in MatchMover, you can import an object into the Workspace and check its behavior in the scene.

NoteYou can bypass this section of the lesson by openningShot_object.mmf. This file can be found in the Tutorials/Supervised_Shotdirectory.

To add a 3D object

  1. Select 3D Scene > New Primitive > Pyramid or click the from the primitive list located on the Toolbar.

    The pyramid primitive appears in the Workspace at the origin of the coordinate system. A Pyramid tab appears in the Parameters window displaying the pyramids position and scale.

    The pyramid is too large for the scene. You can make the pyramid smaller by using MatchMover’s scaling tools.

  2. If the pyramid is not selected, select it now by clicking it in the Workspace or by clicking Pyramid in the Project window under the 3D Scene folder.

  3. Press the Tab key to select the scaling tools.

    The scaling tools appear as a series of light blue, dark blue, green, and red cubes surrounding the pyramid.

  4. Click-drag one of the light blue cubes inward until the Scale X, Y, and Z values are 0.48, or until the base of the pyramid is on the grid.

    Notice that as you drag the cursor, the X, Y, and Z values are scaled uniformly.

  5. Play the sequence in PingPong mode.

    Notice that the tip of the pyramid is out of the camera view. You can use the move tool to change the pyramid’s position so that it remains in the camera view throughout the sequence.

  6. Select the dark blue arrow and move the pyramid along the Z-axis toward the front of the scene until its Pos Z value is about -4.20.
  7. Play the sequence in PingPong mode.

    Notice that the pyramid remains in the camera view throughout the sequence.

    You can now export the sequence and verify its tracking quality in your favorite 3D animation or compositing program.

  8. Select File > Export to export the scene to a file format supported by your 3D animation or compositing program.

    The Export window appears.

  9. In the Export window, do the following:
    • Type a name for your exported file.
    • From the File type list, select a format for you exported file.

      For example, to open your tracked image sequence in Maya, select Maya (*.ma).

    • Click Save.

    The image sequence is exported to the specified file format.