2010

Table Of Contents
6 In the Attribute Editor, select the BubblesShape tab, and then open the
Render Attributes section and set the following:
Particle Render Type: Spheres
Add Attributes For: Click the Current Render Type button.
Radius: 0.5
7 In the Add Dynamic Attributes section of the Attribute Editor, click the
Color button. A window appears that prompts you to choose whether to
add the attribute per object, per particle, or connected to a shader.
8 Turn on Add Per Particle Attribute, then click the Add Attribute button.
This adds an rgbPP attribute to the particle shape node for Bubbles.
Because youre adding this attribute as a per particle attribute, you can
give each particle a different color.
Using creation expressions to set a constant color
To set an attribute that doesnt change during the animation (the particle
color), youll use a creation expression. A creation expression executes when
you go to the start time. It doesnt execute while the animation plays. (For
emitted particles, a creation expression executes for a particular particle when
it is emitted.)
To create a creation expression
1 In the Per Particle (Array) Attributes section of the Attribute Editor,
right-click the rgbPP box and select Creation Expression from the pop-up
menu. Note that the shape node of Bubbles (BubblesShape) is displayed
in the Expression Editor.
When you use an expression to control particle attributes, make sure the
selected object in the Expression Editor is a particle shape node, not the
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