The Decision Point and Photo Eye objects have several useful Pick List Behaviors. Pick Lists are pre-programmed FlexScript functions that simplify common tasks or behaviors in simulation models. Decision Points and Photo Eyes have nearly identical Pick Lists. The main difference between a Decision Point and Photo Eye is in the timing of Triggers. A Decision Point has Triggers that fire when an item arrives at or continues through the point on the conveyor. A Photo Eye has Triggers that fire when an item blocks or clears it. See Decision Point Type Settings and Photo Eye Type Settings for more information on respective Trigger behaviors.
You can add behaviors to a Decision Point or Photo Eye by double clicking on these objects in your simulation model, which opens the Properties dialog box. By default, the Properties dialog box will open to a Decision Point Type tab or a Photo Eye tab that will display various Triggers to which you can add behaviors, as shown in the following images:
You can add a behavior by clicking the Plus sign 
next to the Trigger.
Decision Points and Photo Eye Connections
Decision Points and Photo Eyes are independent objects in the simulation model. This means you can connect them to each other or to other objects in the model using standard input/output or center port connections. Many of the Pick List Behaviors, such as Area Restriction and Send Item, use this feature by default.
The Current and Conveyor Commands
When you add a Pick List Behavior to a Decision Point or Photo Eye, FlexSim will automatically populate the Pick List field with FlexScript commands. Sometimes you might see the command current in some of the commands. In this case, the current command is a reference to the Decision Point or Photo Eye. It is NOT a reference to the conveyor. This means that if you use a command like centerobject(current, 1) in a Pick List field, this will reference the object connected to the Decision Point or Photo Eye's center port 1, NOT the object connected to the conveyor's center port 1. You can use the conveyor command to refer to data and connections on the conveyor. See Basic Modeling Functions for more information on current and object referencing.
Behaviors
The following are some of the available Decision Point or Photo Eye Behaviors:
- Send Item - Can send items to different destinations (such as different conveyor lines) based on criteria you specify
- Stop/Resume - Can stop an item, delay an item, and can set conditions that can make a conveyor motor stop or restart
- Area Restriction - Can create an area that only allows a fixed number of items to flow through a restricted area on the conveyor at a time
- Movement - Can rotate, tilt, or move items at a particular point on a conveyor
- Set Conveyor Speed - Can change the speed of the conveyor based on certain conditions
The other sections in this chapter will discuss each of the available behaviors and their settings.
Certain conveyor objects, such as Decision Points and Photo Eyes can have either local settings or global type settings. That means that you can have settings that are unique to that particular object (local) or you can create a global Type for that kind of object that will allow you to import those settings to other objects of that kind. By default, all Decision Point and Photo Eye settings will be local only and will be labeled as "Custom" in the Type menu. To make the settings a global Type, see Adding and Renaming New Conveyor System Types.
