If you want to control transparency with the Billboard shader (for 2D), you can attach the Shape shader to it and set the Falloff (transparency) controls with it (see Rendering Particle Shapes).
Setting the Particle Transparency
You can create transparent particles using the Billboard, Blob, and Sphere shaders by setting the alpha value in different places, such as from the particle color, the particle color shader, or the particle gradient shader.
As well, you can load the Raytracing > Transparency or Opaque shaders in the render tree and plug them into the Color input of the Billboard/Blob/Sphere shader.
To use the alpha value from the particle type’s color
1. On the particle’s Particle Type > Color property page, set the Alpha value for the level of transparency you want.
2. On the Shading Properties page in the Billboard/Blob/Sphere shader’s property editor, set the Ambient - Type to Use % of Base Color.
3. Set the % of Base to 100% or more to see the effect better.
See Setting the Ambient and Specular Colors for more information.
To use the alpha value from the Particle Color shader
1. In the render tree, select the particle type from the drop-down list.
2. Load the Particle Color shader by choosing Nodes > Texture > More in the render tree. Then open the Particle_Old folder and select Particle_Color.
3. Plug this shader into the Color input of the Billboard/Blob/Sphere shader to override the particle type’s alpha value.
4. In the Particle Color shader’s property editor, select Override Particles - Alpha only (you can deselect RGB if you don’t want to override the particle type color) and set the New Color - Alpha value to the level of transparency you want.
See Rendering the Particle Color for more information.
To use the alpha value from the Particle Gradient shader
1. In the render tree, select the particle type from the drop-down list.
2. Load the Particle Gradient shader by choosing Nodes > Texture > More in the render tree. Then open the Particle_Old folder and select Particle_Gradient.
3. Plug this shader into the Color input of the Billboard/Blob/Sphere shader to override the particle type alpha value.
4. In the Particle Gradient shader’s property editor, select Alpha and set the alpha value and the gradient control to the level of transparency you want.
See Creating Particle Color Gradients (Ramps) for more information.
To use the Transparency shader
1. In the render tree, select the particle type from the drop-down list.
2. Load the Transparency shader by choosing Nodes > Raytracing > Transparency.
3. Plug this shader into the Color input of the Billboard/Blob/Sphere shader to override the particle type alpha value.
4. Set the Transparency shader values to an appropriate level of transparency.
To make the particles reflective
1. In the render tree, select the particle type from the drop-down list.
2. Load the Reflection shader by choosing Nodes > Raytracing > Reflection_Diffuse.
3. Deactivate the Apply Shading option on the Shading Properties page in the Billboard/Blob/Sphere shader’s property editor. This lets the Reflection shader take care of color shading too.
4. Plug this shader into the Color input of the Billboard/Blob/Sphere shader.
Set the Reflection shader values to an appropriate level.
Static Blur (Interparticle Transparency)
With the Blob and Sphere (3D) shaders, you can set the interparticle transparency by selecting the Static Blur option on their Rendering Properties page. This value modifies the alpha channel by the distance between the in and out hit points. It makes the particles transparent on the edges and fully opaque through the center.
With the Sphere shader, overlapping particles accumulate so the blur is less obvious if many particles overlap. The Blob shader brings all particles together into one mass when they get close enough to each other, so individual particles don’t really overlap.
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If you want to control transparency with the Billboard shader (for 2D), you can attach the Shape shader to it and set the Falloff (transparency) controls with it (see Rendering Particle Shapes). |
You can set the Width, which increases the diameter of each particle by this number of units.
The Falloff rate controls how the transparency decreases as it gets further from the particle center. The rate of falloff increases with larger values.
The transparency is greatest when the particle’s normal is perpendicular to the viewing direction. The transparency is not modified when the normal is coincident.
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Using the Textured display mode, you can see the transparency and color burn values for the particles. For more information, see Selecting a Display Type. |
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