Venapps are created and controlled using .vcd or Vensim Custom Definition files. These files define the appearance and behavior of the Venapp using a simple scripting language that is outlined below.
To build a Venapp, you create a .vcd file using the Venapp Editor, Vensim's Text Editor or another editor of your choice. To run a .vcd file, you load the file into the Text Editor, and select the Run Venapp item from the File menu. This item is available only on files having extension .vcd.
When you execute the File>Run Venapp command, Vensim makes a copy of the model you are currently working with along with the associated settings (loaded runs, selected variables and so on). This makes it simple to work on a screen with a quick turnaround time. The fully developed Venapp should, however, load the appropriate model, runs, toolset and custom graph definition, as part of its setup process. Failure to do so may prevent the Venapp from working properly.
You can exit from a Venapp by using an MENU>EXIT command inside the Venapp, or by selecting the close option from the Venapp window menu (or double clicking on the upper left hand corner of the window or clicking the right hand corner under Windows).
To start a Venapp from Windows — without going through the workbench and an editor — you can invoke Vensim with the name of a .vcd file (including the extension). Vensim will load an empty model in the directory you specify, then execute the .vcd file. To work properly, the .vcd file must have a LOADMODEL command.
Note that when starting a Venapp in this manner it might be desirable to use an alternative vensim.ini file (for example to suppress warnings). To do this, just include the name of the alternative .ini file in the command used to start the Venapp (use quotes if there are spaces in directory names). For example
c:\Program Files\vensim\\vensim.exe "c:\My game\game.ini" "c:\My Game\pipeline.vcd"
If you load a .vcd file using the Filel>Open Model command on the Workbench, an empty model in the appropriate directory will be loaded and the .vcd file will be executed. Again, you need to have a LOADMODEL command in the .vcd file.
