Manual 3-D VRML Recording with MATLAB

This topic describes how to manually record a 3-D animation using the MATLAB® interface for a virtual world that is associated with a Simulink® model. In this example, the timing of the animation file derives from the simulation time. One second of the recorded animation time corresponds to one second of Simulink time. You create and record the animation file by interactively starting and stopping the recording from the MATLAB Command Window.

This procedure uses the vrplanets example. It describes how to create a VRML animation filename with the default name format.

  1. Run the Simulink model for vrplanets. In the MATLAB window, type

    vrplanets
    

    The Simulink model appears. Also by default, the Simulink 3D Animation™ Viewer for that model is loaded and becomes active. If the viewer does not appear, double-click the Simulink® 3D Animation block in the Simulink model.

  2. To work with the virtual world associated with vrplanets from the MATLAB interface, retrieve the virtual world handle. Use the vrwhos command. Type

    vrwhos
    

    If the result shows that only one vrworld object is in the workspace, assign its handle directly to a variable. Type

    myworld = vrwho;
    

    If multiple virtual worlds are listed, you must select which of these virtual worlds you want to manipulate. To select the virtual world, you can use indexing or a selection method using a string comparison of virtual world descriptions. For the indexing method, type

    worlds = vrwho;
    myworld = worlds(1);
    

    For the string comparison method, type

    worlds = vrwho;
    myworld = 
    worlds(strcmp('Planets',get(worlds,'Description')));
    
  3. To have the Simulink 3D Animation software manually record the animation, set the RecordMode property to manual. Type

    set(myworld,'RecordMode','manual');
    
  4. Direct the Simulink 3D Animation software to record the animation to a VRML format file. Type

    set(myworld,'Record3D','on');
    
  5. Run the Simulink model. From the Simulation menu, select Mode > Normal, then click Simulation > Run. Alternatively, if you are using the Simulink 3D Animation default viewer, you can run the Simulink model with one of the following from the viewer.

    • From the menu bar, select the Simulation menu Start option to start or stop the simulation.

    • From the toolbar, click Start/pause/continue simulation to start the simulation.

    • From the keyboard, press Ctrl+T to start the simulation.

  6. As the simulation runs, start recording the animation by setting the virtual world Recording property. Type

    set(myworld,'Recording','on');
    

    This turns on the recording state.

  7. When you want to stop the recording operation, type

    set(myworld,'Recording','off');
    

    The Simulink 3D Animation software stops recording the animation. The Simulink 3D Animation software creates the file vrplanets_anim_1.wrl in the current working folder. If the simulation stops before you stop recording, the recording operation stops and creates the animation file.

  8. Stop the simulation. You can use one of the following from the viewer.

    • From the menu bar, select the Simulation menu Stop option to stop the simulation.

    • From the toolbar, click Stop simulation to stop the simulation.

    • From the keyboard, press Ctrl+T to stop the simulation.

    You do not need to manually stop the recording before stopping the simulation. If you do not manually stop the recording, the recording operation does not stop and create the animation file when the simulation stops.

  9. Close and delete the objects if you do not want to continue using them.

Was this topic helpful?