To do these exercises you must run DX and the particle program. If you use this launcher, then you will have open the Sequencer and Image windows. Click on the Windows menu of the Image window and select the Open VIsual Program Editor (VPE) item. The program source should appear.

Remember that you can get help in DX on any module by selecting the "context sensitive help" item from the help menu, then clicking the left mouse button on a module.

• Add a caption.
  1. Add an input tab to the Collect module by selecting it with a mouse click, then typing control-A.
  2. Add a Caption module by:
     1. Clicking on the Annotation Catagory at the upper-left side of the VPE.
     2. Clicking on the Caption item of the list in the lower-left side of the VPE.
     3. Clicking to the right side of the Collect module to place the new Caption module.
  3. Connect the output tab of the Caption module to the new input of the Collect.
  4. Double-Click the Caption module and type a test caption into the "string" field.
  5. Execute the program by selecting the Execute Once item from the Execute menu.

  The program should now look like this, (with the Caption dialog box open) and will generate an image with a caption. You can change the position of the caption in the image by modifing the position parameter which defaults to the bottom-center of the image.

• Make a caption which shows the time step.
  1. Add an input tab to the Collect module by selecting it with a mouse click, then typing control-A.
  2. Add Caption and Format modules by:
     1. Clicking on the Annotation Catagory at the upper-left side of the VPE.
     2. Clicking on the Caption item of the list in the lower-left side of the VPE.
     3. Clicking to the right side of the Collect module to place the new Caption module.
     4. Clicking on the Format item of the list in the lower-left side of the VPE.
     5. Clicking above the just-added Caption module to place the new Format module.
  3. Connect the output tab of the Caption module to the new input of the Collect.
  4. Connect the output tab of the Format module to the first input of the Caption.
  5. Connect the output tab of the Sequencer module to the second input of the Format.
  6. Double-Click the Format module and type "Time Step=%d" into the "template" field.
  7. Execute the program by clicking on the foward play button on the Sequencer.

  The program should now look like this, and will generate an image with a time-varying caption.

• Change the color of the disks.
  1. Disconnect the wire connecting the Glyph and Collect modules by clicking on the end attached to the collect module and dragging the wire off.
  2. Add a Color module by:
     1. Clicking on the Transformation Catagory at the upper-left side of the VPE.
     2. Clicking on the Color item of the list in the lower-left side of the VPE.
     3. Clicking to the left side of the Collect module to place the new Color module.
  3. Connect the output tab of the Glyph module to the first input of the Color module.
  4. Connect the output tab of the new Color module to the input of the Collect.
  5. Double-Click the Color module and type a color name (e.g. "red") into the "color" field.
  6. Execute the program by selecting the Execute Once item from the Execute menu.

  The program should now look like this, (with the Color dialog box open) and will generate an image with red disks.

• Make the particles look spherical.
  1. Double-Click the Gylph module and type "sphere" into the "type" field.
  2. Execute the program by selecting the Execute Once item from the Execute menu.

  The glyph dialog box should now look like this, and will generate an image with red disks.

• Add an interactor to set particle diameter.
  1. Add an input tab to the Compute module by selecting it with a mouse click, then typing control-A.
  2. Add an Scalar module by:
     1. Clicking on the Interactor Catagory at the upper-left side of the VPE.
     2. Clicking on the Scalar item of the list in the lower-left side of the VPE.
     3. Clicking to the right side of the Compute module to place the new Scalar module.
  3. Connect the output tab of the Scalar module to the second input of the Compute.
  4. Double-Click the Scalar module to open a new control panel.
  5. On the control panel set the desired radius (e.g. 0.1)
  6. Double-click the Compute module and change the "expression" to "b" (that is, make the output equal to input b).
  7. Execute the program by clicking on the foward play button on the Sequencer. As the program steps forward change the interactor in the control panel.

  The program should now look like this, and will generate an image with larger disks (if the interactor is set to 0.1).