When you use the shelf tools to set up your particle system, it creates a POP network node inside a geometry object. This lets you render the particle system directly (since Mantra always renders objects).
By default, Mantra replaces particles with tiny spheres. You can also render particles as points, or replace particles at render time with images (called sprites) or geometry.
Render particles as points
Select the object containing the particles.
In the parameter editor, click the Render tab, then click the Geometry sub-tab.
Turn on Render As Points.
You can still use the particles scale (
pscale) attribute to control the size of the points in the render.
Instance geometry on particles (particle replacement)
|Instance geometry on particles|
For specific parameter help see the Instance node help.
|Rotate the instanced geometry to an angular value|
|Rotate the instanced geometry using torque|
For specific parameter help see the Torque node help.
|Make the instanced geometry look at an object|
|Make the instanced geometry look at a plane|
Set the rendered appearance of particles
|Control the appearance of non-sprite particles|
|Display sprites in the viewport|
|Control the appearance of sprites|
Sprites always face the camera.
For specific parameter help see the Sprite node help.
If Resolve SHOP Path is on, the Sprite SHOP path is resolved relative to this node, and the
To see particle alpha in the 3D viewport, the particles must be displayed as sprites. By default particles are displayed as points.
Press D in the scene view to open the Display Options window.
Click the Particles tab and set Display particles as Sprites.
Close the window.
On the Ramp sub-tab of the Color tab, set the Lookup parameter to
You will need to use a shader that will read the Alpha attribute in order to render. For example, VEX Layered Surface.
When calculating motion blur, Mantra by default assumes the geometry of an object is unchanging, and blurs it as a whole. For a particle system obviously the points are moving, so you need to turn on velocity blur to use the velocity (
v) attribute of the points to blur them individually.
So, to enable motion blur on particles you must enable it on the object as well the render node.
|Enable velocity blur on an object|
Turn on Geometry velocity blur.
|Enable motion blur on a render node|
Rendering Attributes for Points and Particles
To change the rendering style of particle systems, use a Render POP.
You must re-simulate the POP network for any changes in the render POP to take effect.
The following attributes can be added to points, verticies, entire particle systems, and primitives: