The Particle Sampler Info node is a particle utility that lets you:
The Particle Sampler Info node provides all the functionality of the particle color mapper, transparency mapper, incandescence mapper, and age mapper. See Particle Sampler Info node and Create a Particle Sampler Info node.
Using the Particle Sampler Info node
The Particle Sampler Info node provides particle shape attributes to either a particle shader, texture, or texture placement node for use in software rendering.
When you use a Particle Sampler Info node, you connect one or more of its outputs to attributes of a particle shader or texture placement node. This tells the shader to get the per-particle information from the Particle Sampler Info node. It also tells the Particle Sampler Info node which attributes to get from the particle shape.
The Particle Sampler Info node has the following types of outputs:
You still have to add attributes to the particle shape, where applicable. The Particle Sampler Info node just gets attribute values, if they are present. For example, making a connection from the Particle Sampler Info node parentU to the shader tells the sampler info node to get parentU if it’s there, and use it in the shading. You still have to add parentU to the particle shape.
The Particle Sampler Info node has no association with any particular camera, unlike the samplerInfo node. The two nodes are similar in that both provide data to shaders to use in shading samples. They are different in that much of the data the samplerInfo node provides is camera-dependent.
Strategies for using the Particle Sampler Info node
There are two basic strategies for using the Particle Sampler Info node to control your particles:
The advantage of this strategy is two-fold: you can use any type of texture, and you can use the controls on the texture placement node.
The main advantage of this strategy is that it lets you control the per-particle attribute using expressions, ramps, or the Component Editor and see the result in the shading or texture node.
In addition to its many outputs for predefined attributes of the particle shape (such as position, radiusPP, and so on), the Particle Sampler Info node includes ten predefined outputs for user-defined attributes, which you can add to the particle shape.
Five of these are scalar and five are type; they are called userScalar1PP, userVector1PP, and so on.
If you connect one of these to a shading attribute, the Particle Sampler Info node looks for an attribute of the identical name on the particle shape, and fetches those values. For example, if you connect userScalar1PP to shader noise, then the Particle Sampler Info node looks for a userScalar1PP attribute on the particle shape.