Modifying the Particle Emitter in the Dashboard


You've created particles with a simple click of the Make Particles button; now let's take a look at the Emitter Dashboard and make a few adjustments. To understand the emitter parameters, you need to understand that particles are considered living objects within your project. They are born and have a pre determined life span; you can control their "birthrate" and when they "die." Let's take a look.

1.

Press D to open the Emitter Dashboard.

The Emitter Dashboard includes six parameters that you can adjust. You control three of the parameters by sliders. You control the other three by dragging the parameters within the Emission Control display.

The Birth Rate slider adjusts how many particles are born (created) every second.

The Life slider adjusts how many seconds the particles live.

The Scale slider adjusts the scale (size) of the particles, based on the size of the original object. If the scale is 100 percent, the particles are the same size as the original object. If the scale is 50 percent, the particles are half the size of the original object.

The Emission Control display in the lower half of the Emitter Dashboard allows you to manipulate three particle system parameters: Emission Range, Emission Angle, and Speed.

2.

On the Emitter Dashboard, drag the Birth Rate slider toward the left until the Birth Rate value is 5.

There are now only five AquaBall particles born every second. The default number of particles born per second is 30. Now let's adjust the Life parameter.

3.

On the Emitter Dashboard, drag the Life slider toward the left to around 2 seconds.

The AquaBall particles now disappear 2 seconds after they are born, which makes them look like they are popping before they reach the edges of the frame.

Let's extend the particles' lives so that the AquaBalls can reach beyond the edges of the frame and we don't have to witness their demise.

4.

Drag the Life slider to around 4 seconds.

The AquaBalls move in all directions from the center of the frame and have enough time to exit the frame before they reach the end of their lives.

5.

Drag the Scale slider toward the left to change the scale of the particles to around 50, which is 50 percent of the original object's size.

NOTE

The precision of the Dashboard sliders is limited, so you may not be able to set the exact number you are aiming for. For example, 51 may be as close to 50 percent as you can get in the Dashboard. To set exact parameter values, you'll need to change the parameters in the Inspector.


Now let's take a closer look at the Emission Control parameters.

Working with the Emission Control Parameters

What is emission control, anyway? A particle emitter works like a deluxe massage-style showerhead. If you've ever used one of those, you know that you can adjust the rate and angle, or shape, of the water flow by turning the dial around the nozzle of the showerhead. The same principle applies to an emitter. You can use the Emission Control display to adjust the range, angle, and speed of the flow of particles from the emitter.

You can adjust the Emission Control parameters similar to the way you adjust the Throw parameters in the Dashboard. Let's start by adjusting the emission range.

The emission range for the flow of particles functions like the flow settings on a massage showerhead. In spray mode, the showerhead sprays a steady flow of water from the entire diameter of the showerhead (360 degrees). If you adjust the dial on the showerhead, you can change the flow of water to the deep massage mode that focuses the water to a narrow stream from one particular spot on the nozzle.

You change the emission range by dragging the two points on the outer ring of the graphical control. The wider the range, the wider the flow of particles. The narrower the range, the more focused the flow of particles. By default, the particle flow is the full 360-degree range, which means that particles flow outward in all directions from the emitter. The number of arrows visible within the control decreases as you decrease the emission range.

Let's adjust the emission range to narrow the flow of AquaBall particles to a single stream flowing toward the right.

1.

Drag the points on the outer ring toward the right center edge of the ring to restrict the flow of particles to a single stream flowing toward the right.

The number of arrows in the Emission Control display is determined by the angle of the emission range. Since the emission range is limited to a single stream of particles, only one arrow appears in the graphical display. The length of the arrow or arrows in the Emission Control display determines the speed of the particle flow. The longer the arrow, the faster the particles move. Let's speed up the flow of particles.

2.

Drag the arrow toward the edge of the outer ring in the graphical control to make the arrow longer and the speed of the particles faster.

Adjusting the angle that the arrow or arrows are pointing modifies the angle of the particle flow.

Let's move the angle of the particles counterclockwise so the particles flow toward the upper right of the frame.

3.

Drag the arrow counterclockwise until the particles flow toward the upper-right corner of the frame.

4.

Press Cmd-S to save your progress.

Now that you've modified the particle emitter in the Dashboard, let's look at some of the parameters in the Inspector.



    Apple Pro Training Series Getting Started with Motion
    Apple Pro Training Series: Getting Started With Motion
    ISBN: 0321305337
    EAN: 2147483647
    Year: 2005
    Pages: 283
    Authors: Mary Plummer

    flylib.com © 2008-2017.
    If you may any questions please contact us: flylib@qtcs.net