Using different Timer compounds, you can set up particle events to happen when a certain time limit has been reached. You set a condition that will start a timer. The timer runs its course according to the time you’ve specified. Then when the time is up, the particle event happens and the particles change state.
You can set up particle timers either with or without using the State compounds. Both methods are described here.
Using Particle Timers in a State System
You can create the same effect as previously described using the state system.
To set up a particle timer using a state system
1. Create a particle simulation—see Creating ICE Particle Emissions.
2. In the ICE view, click the Task tab on preset manager on the left and select Particles.
3. Drag a State Machine compound from the States group into the ICE view and plug it into a port on the ICETree node.
4. Disconnect the Simulate Particles node from the ICETree node.
5. Drag two State compounds from the States group into the ICE view and plug each of them into consecutive Execute State ports of the State Machine compound.
6. Drag the Start Timer compound from the Timers group into the ICE view and plug it into the Execute on Trigger port of the first State compound. This compound starts a timer when a trigger value is reached (see next step) and lets it run for the amount you specify.
In the Start Timer property editor, give this timer a name and set the amount of time (in seconds) that you want the particles to be in their first state.
7. Drag a Test compound from the Conditionals group to act as the trigger for the timer to start. Plug it into the Trigger port of the first State compound.
In our example, the Test Particle Position is used so that when the particles reach a certain position value in Y, the Start Timer begins counting.
8. Drag the Test Timer compound from the Timers group into the ICE view and plug it into the Trigger2 port of the first State node. This acts as a trigger for activating the second state of the particles: when the time value defined in the Start Timer compound has been reached, the trigger is pulled.
9. Drag some compound or node to set up the state of the particles for when the timer value is reached, such as a Set compound. Plug it into an Execute port of the second State node.
In our example above, the Set Particle Color compound is used to change the particle color when the Test Timer trigger value is reached.
Using Particle Timers with If Nodes
To set up a particle timer
1. Create a particle simulation—see Creating ICE Particle Emissions.
2. From the preset manager, drag two If nodes from the Tool > Execution group into the ICE view and plug them into consecutive ports on the ICETree node.
Note that you can use nodes or compounds other than the If node: the criteria is that the node needs to cause an execution.
3. Switch to the Task > Particles tab in the preset manager.
4. Drag the Start Timer compound from the Timers group into the ICE view and plug it into the If True port of the first If node. This compound starts a timer when a trigger value is reached (see next step) and lets it run for the amount you specify.
In the Start Timer property editor, give this timer a name and set the amount of time (in seconds) that you want the particles to be in their first state.
5. Drag a Test compound from the Conditionals group to act as the trigger for the timer to start. Plug it into the Condition port of the first If node.
In our example, the Test Particle Position is used so that when the particles reach a certain position value in Y, the Start Timer begins counting.
6. Drag the Test Timer compound from the Timers group into the ICE view and plug it into the Condition port of the second If node. This acts as a trigger for activating the second state of the particles: when the time value defined in the Start Timer compound has been reached, the trigger is pulled.
7. Drag some compound or node that makes the particles change when the timer value is reached, such as a Set compound. Plug it into the If True port of the second If node.
In our example above, the Set Particle Color compound is used to change the particle color when the Test Timer trigger value is reached.
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