4.3   Specifying Parameters

After selecting an operator, its parameters are displayed in the operator window. They are grouped by iconic and control parameters. The icons next to the parameter names denote the parameter type: Input vs. output (see figure 4.3). The semantic type is displayed to the right of the parameters. Parameters are specified in the text fields. The first parameter gets the input focus.

Figure 4.3: Specifying parameters.

Iconic output parameter

Control input parameter

Semantic type

Data type

File selection dialog

Enter Clip into the text field Image. The image will be stored in this variable. Next, enter 'clip' into the text field FileName. You can press Tab to go to the next input field. Pressing Shift+Tab takes you back to the previous field. This way you can enter all parameters without using the mouse.

Click OK to add the operator to the current program and execute it. This will do the following:

• An operator call is added as the first line of the current program.
• The IC is advanced, so that additional lines will be added after the inserted line.
• The character * is added to the window title to indicate unsaved changes in the current program. The current procedure (main) is also marked with * in the program window.
• The program line is executed and the PC is advanced. To be more precise: All the lines from the PC to the IC are executed which makes a difference when adding program lines in larger programs.
• The image is displayed in the graphics window.
• The status bar is updated, and the execution time of the operator read_image is displayed and the format of the loaded image is reported.
• The output variable Clip is created and displayed in the variable window.
• The operator window is cleared and ready for the insertion of the next operator.