User Manual

For simple, fast-rendering particle systems, it is recommended to leave the Automatic Pre-Roll
option on. For slower particle systems with long time ranges, it may be desirable to only
Pre-Roll manually, as required.
Only Render in Hi-Q
Selecting this checkbox causes the style of the particles to be overridden when the
Hi-Q checkbox is deselected, producing only fast rendering Point-style particles. This is
useful when working with a large quantity of slow Image-based or Blob-style particles.
To see the particles as they would appear in a final render, simply enable the
Hi-Q checkbox.
View
This drop-down list provides options to determine the position of the camera view in a
3D particle system. The default option of Scene (Perspective) will render the particle
system from the perspective of a virtual camera, the position of which can be modified
using the controls in the Scene tab. The other options provide orthographic views of
the front, top, and side of the particle system.
It is important to realize that the position of the onscreen controls for Particle nodes is
unaffected by this control. In 2D mode, the onscreen controls are always drawn as if the
viewer were showing the front orthographic view. (3D mode gets the position of
controls right at all times.)
The View setting is ignored if a Camera 3D node is connected to the pRender node’s
Camera input on the node tree, or if the pRender is in 3D mode.
Conditions
Blur, Glow, and Blur Blend
When generating 2D particles, these sliders apply a Gaussian blur, glows, and blur blending to
the image as it is rendered, which can be used to soften the particles and blend them. The
result is no different than adding a Blur after the pRender node in the node tree.
Sub-Frame Calculation Accuracy
This determines the number of sub-samples taken between frames when calculating the
particle system. Higher values increase the accuracy of the calculation but also increase the
amount of time to render the particle system.
Pre-Generate Frames
This control is used to cause the particle system to pre-generate a set number of frames before
its first valid frame. This is used to give a particle system an initial state from which to start.
A good example of when this might be useful is in a shot where particles are used to create the
smoke rising from a chimney. Set Pre-Generate Frames to a number high enough to ensure that
the smoke is already present in the scene before the render begins, rather than having it just
starting to emerge from the emitter for the first few frames.
Kill Particles That Leave the View
Selecting this checkbox control automatically destroys any particles that leave the visible
boundaries of the image. This can help to speed render times. Particles destroyed in this
fashion never return, regardless of any external forces acting upon them.
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