Visibility group> Obscuring particles with a layer

Trapcode Particular is applied to a 2D layer and its particles live in their own 3D world. This means other layers in the composition won't automatically obscure the particles. The two Obscuration controls provide a way to insert a 3D layer into the particles' world.

Read our tutorial 'Using an Obscuration Layer' at the bottom of this page.

Technical notes:

- The Obscuration Layer cannot be a text layer. If you must use text, create the text in a pre-comp and load in that pre-comp.
- The Obscuration Layer must have 'Continuous Rasterize' switched off in the Timeline layer switches.
- The Obscuration Layer must have '3D' enabled in the Timeline layer switches.
- Obscuration does not work with semi-transparent layers.
- This obscuration is not anti-aliased so its effect can look a bit rough on the layer edges. In many cases, this issue doesn't matter because particles are small and move fast.

Obscuration Layer

The Obscuration Layer provides a way to insert a 3D layer into the particles' world. Any 3D layer in the comp can be used to obscure particles.

To do this, place the Obscuration Layer below the particle layer in the Timeline. Make sure its 3D switch is checked in the Timeline. Then select that layer in the Obscuration popup.

At left , the Obscuration Layer choose its layer. At right, the 3D switch is turned on for the source layer.

Left to right, before and after Obscuration Layer is enabled.

Also Obscure With

The Layer Emitter, Wall and Floor can be set up to obscure particles with this control. Make sure to place any layer that will obscure particles below the particle layer in the Timeline.

Tutorial: Using an Obscuration Layer

Create a new comp (Ctrl/Cmd-N), make it 640*480 at 30 fps. 5 seconds long. Name it 'Main'.

Create a new comp-sized Solid (Ctrl/Cmd-Y), and name it 'Particles'. Make sure to select Make Comp Size before clicking OK.

Apply Effect> Trapcode> Particular to the Solid.
To be able to navigate easily in the scene, create a composition camera. Select Layer>New>Camera and use the 28mm preset.
Now create the layer that will obscure particles. Create a 200*200 Solid that is red. Name it 'Obscure'. Switch the Solid to 3D by clicking the 3D layer switch in the Timeline. Make sure the Continuous Rastorize layer switch is turned off.

Go to Time 03:00 (3 seconds). This is what we have so far:

Try orbiting around the scene with the Unified Camera Tool (press 'C' to access). Notice that the particles always remain behind the Solid.
To fix this, let's move the 'Obscure' Solid layer below the 'Particles' Particular layer in the Timeline. Select the 'Particles' layer again. Now set Visibility> Obscuration Layer to the 'Obscure' layer.

Now try orbiting again and notice how the particles are correctly obscured by the Solid. You're finished!

Left to right, before and after Obscuration Layer is chosen.