Screen Emitter
Updated: 4 Dec 2023
Emit particles from objects within the screen space.
Screen Emitter
Method #
This node emits particles only from objects within the cameras view. Useful for efficiently emitting particles across a large dynamic scene, or creating apparent point clouds from meshes in the camera view. Particles can be emitted from other layers by adding a Render Layer node as an input to this node.
The transformation values of this node will be inherited by its children. Furthermore, Affectors, Shading, and Rendering nodes will only be effective to the particles emit by this emitter.
Parameters
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
Parameter Details Position X
The objects position along the local x-axis.
Position Y
The objects position along the local y-axis.
Position Z
The objects position along the local z-axis.
Rotation Heading
The objects rotation around the local y-axis.
Rotation Pitch
The objects rotation around the local x-axis.
Rotation Bank
The objects rotation around the local z-axis.
Scale X
The objects scale along the local x-axis.
Scale Y
The objects scale along the local y-axis.
Scale Z
The objects scale along the local z-axis.
Control the inheritance of the transforms from the parent.
Parameter Details Position
Toggle inheritance of the Position from the parent.
Rotation
Toggle inheritance of the Rotation from the parent.
Scale
Toggle inheritance of the Scale from the parent.
World Position Only
Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties.
Inherit Time
Toggle inheritance of time from the parent.
These properties control the core behaviours of the node.
Parameter Details Flip Image
Flip the image input vertically.
Luminance Offset Scale
Bias the particles in depth by the luminance of the source pixel.
Use Thickness
Toggle whether emit the particles on a 2d plane, or in three dimensions.
Thickness
Change the thickness of the three dimensional area the particles can spawn in. Only functions if ‘Use Thickness’ is on.
Pixel Cull/Thickness Mode
Change how the depth of the particle generation is calculated.
- Alpha Channel : lower alpha values will have greater depth.
- Luminescence : darker parts of the image will have greater depth.
- Luminance * Alpha Channel : luminance values are multiplied by alpha values and lower values after which are given greater depth.
Alpha Threshold
Limit where the particles will spawn based on their source alpha.
Image Colour Adaption
How much the particle colours adapt to the image colours.
Particle Use Image Alpha
Toggle whether particles use the image alpha.
Emission Velocity Normal Direction
How great a velocity the particles are given in the normal direction of the object when spawned.
Limit Emissions Per Pixel
Toggle whether the number of particles that can be emitted per pixel can be limited.
Max Emissions Per Pixel
The maximum number of particles that can emit per pixels. Only functions if “Limit Emissions Per Pixel” is true.
Emission Area Min
Control the minimum area that the particles will be emitted.
Emission Area Max
Control the maximum area that the particles will be emitted.
These properties control how the particles are emit from the node, and their core life properties.
Parameter Details Emitter Active
Change whether the emitter is on or off.
Randomness
How much randomness is added in the particles movement.
Life
Control how low long each particle exists for.
Life Randomness
Control the randomness for the life of each particle.
Emission Rate
What percentage of the particles are emitted from the emitter per second.
Max Particle Count
Set a maximum particle count for the emitter.
Respawn Enabled
Toggle whether a particle can respawn.
Tints the particles colours from the emitter. To enable, add an colour ramp input to this node.
Parameter Details Colour Selection Mode
Choose how the input colour affects the particles.
- Input Colour : The first colour input is the only colour output.
- Selected Single Colour : Uses the colour selection parameter to decide which colour to use.
- Emission Time : Colour is selected based on time at which the particle is emitted.
- Random Colour : the colour is selected randomly at the particles creation.
Colour Selection Parameters
A number used to select the colour output.
These properties allow the motion vectors from an input optical flow node to move the emitted particles.
Parameter Details Motion Vector Effect
Scales effect of motion vectors on the motion of the particles.
Time Offset
Offset the time the
These properties control the material the particles use for emission.
Parameter Details Colour
RGB colour of particles.
Diffuse
Control how much the light is scattered from the surface of the object.
Emissiveness
Control how much light is emitted by the particle.
Life Colour Affecter Weight
Controls how much the result of any Life Colour Shading nodes are blended with the particle’s colour.
Particle Scale
Scale the size of the particle.
Dof Amount
How much depth of field effects the particles material.
Density
The density, for use in some simulations.
Temperature
The density, for use in some simulations.
Cooling Rate
The cooling rate, for thermal dynamics simulations.
Density Decay
Control the rate of decay in the density.
Fade In Time
What percentage through the particles life span the particle fades in.
Fade Out Time
What percentage through the particles life span the particle fades out.
Inputs
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
| Parameter | Details |
|---|---|
| Position X | The objects position along the local x-axis. |
| Position Y | The objects position along the local y-axis. |
| Position Z | The objects position along the local z-axis. |
| Rotation Heading | The objects rotation around the local y-axis. |
| Rotation Pitch | The objects rotation around the local x-axis. |
| Rotation Bank | The objects rotation around the local z-axis. |
| Scale X | The objects scale along the local x-axis. |
| Scale Y | The objects scale along the local y-axis. |
| Scale Z | The objects scale along the local z-axis. |
Control the inheritance of the transforms from the parent.
| Parameter | Details |
|---|---|
| Position | Toggle inheritance of the Position from the parent. |
| Rotation | Toggle inheritance of the Rotation from the parent. |
| Scale | Toggle inheritance of the Scale from the parent. |
| World Position Only | Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties. |
| Inherit Time | Toggle inheritance of time from the parent. |
These properties control the core behaviours of the node.
| Parameter | Details |
|---|---|
| Flip Image | Flip the image input vertically. |
| Luminance Offset Scale | Bias the particles in depth by the luminance of the source pixel. |
| Use Thickness | Toggle whether emit the particles on a 2d plane, or in three dimensions. |
| Thickness | Change the thickness of the three dimensional area the particles can spawn in. Only functions if ‘Use Thickness’ is on. |
| Pixel Cull/Thickness Mode |
Change how the depth of the particle generation is calculated.
|
| Alpha Threshold | Limit where the particles will spawn based on their source alpha. |
| Image Colour Adaption | How much the particle colours adapt to the image colours. |
| Particle Use Image Alpha | Toggle whether particles use the image alpha. |
| Emission Velocity Normal Direction | How great a velocity the particles are given in the normal direction of the object when spawned. |
| Limit Emissions Per Pixel | Toggle whether the number of particles that can be emitted per pixel can be limited. |
| Max Emissions Per Pixel | The maximum number of particles that can emit per pixels. Only functions if “Limit Emissions Per Pixel” is true. |
| Emission Area Min | Control the minimum area that the particles will be emitted. |
| Emission Area Max | Control the maximum area that the particles will be emitted. |
These properties control how the particles are emit from the node, and their core life properties.
| Parameter | Details |
|---|---|
| Emitter Active | Change whether the emitter is on or off. |
| Randomness | How much randomness is added in the particles movement. |
| Life | Control how low long each particle exists for. |
| Life Randomness | Control the randomness for the life of each particle. |
| Emission Rate | What percentage of the particles are emitted from the emitter per second. |
| Max Particle Count | Set a maximum particle count for the emitter. |
| Respawn Enabled | Toggle whether a particle can respawn. |
Tints the particles colours from the emitter. To enable, add an colour ramp input to this node.
| Parameter | Details |
|---|---|
| Colour Selection Mode |
Choose how the input colour affects the particles.
|
| Colour Selection Parameters | A number used to select the colour output. |
These properties allow the motion vectors from an input optical flow node to move the emitted particles.
| Parameter | Details |
|---|---|
| Motion Vector Effect | Scales effect of motion vectors on the motion of the particles. |
| Time Offset | Offset the time the |
These properties control the material the particles use for emission.
| Parameter | Details |
|---|---|
| Colour | RGB colour of particles. |
| Diffuse | Control how much the light is scattered from the surface of the object. |
| Emissiveness | Control how much light is emitted by the particle. |
| Life Colour Affecter Weight | Controls how much the result of any Life Colour Shading nodes are blended with the particle’s colour. |
| Particle Scale | Scale the size of the particle. |
| Dof Amount | How much depth of field effects the particles material. |
| Density | The density, for use in some simulations. |
| Temperature | The density, for use in some simulations. |
| Cooling Rate | The cooling rate, for thermal dynamics simulations. |
| Density Decay | Control the rate of decay in the density. |
| Fade In Time | What percentage through the particles life span the particle fades in. |
| Fade Out Time | What percentage through the particles life span the particle fades out. |
| Name | Description | Typical Input |
|---|---|---|
| Render Layer | Layer to render the particles from. | Render Layer |
| Colour Control | Control the colours of the particles on emission. | Colour Ramp |
| Transform Modifiers | Apply the transforms of another node to this node. | Null |
| Target Node | Modifiy the rotations of the node to always direct the z axis towards the input. | Null |
| Local Transform Override | Apply the transforms of another node to this node, relative to its parent. | Null |
