Trapcode Particular

Using Curves

There are six curves in Trapcode Particular. The controls are: Emission over Parent Life, Velocity over Life, Color over Life, Size over Life, Opacity over Life, and Blend Mode over Life.


Graph Basics

In each instance of the curve, the controls behave in a similar way. The vertical axis of all curves is used to indicate the amount of an attribute. The horizontal axis is used to determine where those values fall in time, the left side controlling the beginning of the animation, and the right side of the graph controlling the end of the animation.

For example, in the Size over Life curve, if we drew a line that started on the bottom left (which indicates a small size value at the beginning of our animation) and ended at the upper right corner (which indicates a large size value at the end of the animation), our particle size would get larger over time.


Animating Curves

Curves in Particular can now be animated. You can create two completely different Curves, and Particular will interpolate between them over time. Simply click the stopwatch next to the Curve to record the current shape of the Curve graph, and then animate this as you would any other After Effects property.


Curves Presets

In the upper right corner of the curve interface, you’ll find a Presets drop down with many common curve types. While you get the most control from drawing your own curves in the graph (discussed below), using the curve presets can provide a faster shortcut to common curve shapes, or provide a jumping off point that you can customize with your own drawing. Note that the presets become significantly more powerful when using the other interface controls in the curve (discussed below).

There are six preset shapes to choose from:

  1. the top preset resets the curve, as it sets the attribute to be at full value for the life of the particle.
  2. this preset creates a diminishing value over time
  3. this preset causes a quicker initial increase in value and then a slower reduction
  4. this preset causes a smooth rise and a smooth reduction in value
  5. this preset causes the value to have an eased, but sudden reduction around the middle of the life of the particle
  6. this preset creates a similar effect to preset #5, but the reduction in the middle of the particle’s life is slightly more gradual, and the end of the life has several “spikes” of a high value. This preset is often used for Opacity over Life, as it can create a sparkle right before the particle dies.


Drawing Curves Manually

You can also create curves by manually drawing them in with your mouse in the main curve window. Simply click and drag in the graph area with the pencil tool, and wherever you click will become the value for that attribute at that place in time in the life of the particle.


Adjust the Curve

When manually drawing curves, you have two tools: a pencil (default), and a pen. The pencil allows you to draw the path as you would like. The pen tool allows you to set bezier control points on a curve, and then adjust those points to achieve the desired curve in the graph. Note that simply selecting the pen tool will also instantly apply a significant amount of smoothing to your curve.

These tools can also be used in tandem. For example, a curve can be quickly drawn manually with the pencil, and then by clicking the pen tool, the rough curve becomes smoother and easier to adjust.



In the upper right hand corner of the graph, the left-facing arrow allows you to undo the last action performed in the curve. After undoing an action, the arrow will face to the right and will allow you to redo the action just undone.



In the far right corner of the graph is the circular arrow, which is the Reset button. This button allows you to reset the curve control to get a fresh start.



The right side of the interface has Copy and Paste buttons that you can use to mimic behaviors in various curves throughout Particular, and even in other instances of Particular in other compositions in After Effects. Simply click the Copy button, and then in another curve, click the Paste button.




If you are using the pencil, you can click the smooth button to smooth out your results. This feature is gradually iterative, meaning that each time you click it, the curve result gets smoothed slightly.







Next to the Smooth button is the Randomize button.

This usually creates an extremely random result in the curve that would typically be very difficult to create manually.



Flip Curve

To the right of the Randomize button, we find the Flip Curve button.


By clicking the Flip Curve button, the curve is flipped along the horizontal axis. This causes the results from the birth and death of the particle to be reversed.