# Postprocessing Effects¶

## Motion Blur¶

The motion blur effect can be used to improve the realism of an interactive scene. It is displayed as picture blurring when the camera or objects move.

### Activation¶

Activate the Motion Blur panel on the Render tab.

Factor
Effect appearance ratio. The higher this value is the stronger is the motion blur.
Decay Threshold
Blur fade-out ratio. The higher this value is the more distinct is the effect. The default value is 0.01.

## Depth of Field¶

The depth of field effect (DOF) can be used to accentuate a part of a scene. It is displayed as picture blurring nearer and further from the camera focus.

### Activation¶

1. Select an active camera and go to its settings panel Camera (Object Data).

2. Then two options are available:

• Select an object to use as the camera’s focus in the Focus option of the Depth of Field panel. In this case moving away or approaching this object will cause a corresponding correction of the camera focus.
• Set a non-zero value for the Distance on the same panel (in Blender units = meters). In this case the camera focus will be located at this distance from the camera and will move together with it.

Focus
Sets the focal object. By default, this field is empty.
Distance
This parameter defines the focal distance. Available only if the Focus parameter hasn’t been set beforehand (if the corresponding field is empty). Set to zero by default.
Front Start

This sets the distance (in meters) from the focus to the nearest plane (relative to the camera) behind which blurring effect starts to occur. The default value is 1.0.

This parameter is available only if the High Quality (Bokeh) parameter is enabled.

Front End
This sets the distance from the camera and the nearest plane (relative to the camera) behind which blurring effect reaches maximum strength (defined by the Power value). Default value is 5.0.
Rear Start

This sets the distance from the focus to the furthest plane (relative to the camera) behind which blurring effect starts to occur. The default value is 1.0.

This parameter is available only if the High Quality (Bokeh) parameter is enabled.

Rear End
This sets the distance from the camera to the furthest plane (relative to the camera) behind which blurring reaches maximum strength (defined by the Power value). Default value is 5.0.
Power
Blurring ratio. The value of this parameter can vary from 0.1 to 10. The default value is 2.0.
High Quality (Bokeh)

This enables high quality rendering of the depth of field effect. Activating this option:

• Enables bokeh effect and makes available the Bokeh Intensity parameter for adjusting the strength of the effect.
• Enables the Front Start and Rear Start parameters for setting soft transition between the distance from camera where the effect start to occur and the distance where it reaches its full strength.
• Enables Foreground Blur parameter that is described below.

The parameter is disabled by default.

Bokeh Intensity
This value sets the strength of the bokeh effect. It can vary from zero to 1.0. Set to 0.3 by default.
Foreground Blur
Enabling this option makes the engine to blur the silhouettes of the foreground objects, improving the quality of the effect at the cost of slight performance decrease. Disabled by default.

## Screen-Space Ambient Occlusion¶

The screen-space ambient occlusion (SSAO) effect can be used to fake complex light reflections from objects. The basis of this effect is that the space between close objects is less accessible for diffused light and hence is darker.

### Activation¶

Activate the Ambient Occlusion SSAO panel under the Render tab and set the Render Shadows parameter to AUTO or ON on the Render > Shadows panel.

The spherical sampling radius multiply factor when transferring from the internal sampling ring to the external one. The default value is 3.0.
Use Hemisphere
Use Blur Depth Test
Use edge-preserving blur to SSAO if flag will be turned on. Otherwise, it uses blur which averages a 4x4 rectangle around each pixel.
Influence of depth difference between samples on blur weight. It uses with Use Blur Depth Test activated flag. The default value is 1.0.
Influence
SSAO appearance factor. The default value is 0.7.
Distance Factor
Factor of SSAO decay with distance. The default value is 0.0 (i.e. no decay).
Samples
Number of samples (the more samples there are the better is the quality but the poorer is the performance). The default value is 16.

## God Rays¶

The god rays effect (aka crepuscular rays) simulates well-known natural phenomenon - the shining of illuminated air parts.

### Activation¶

Activate the God Rays panel under the Render tab.

Intensity
The effect appearance factor. The default value is 0.7.
Maximum Ray Length
Rays length factor. Defines the step between samples of radial blurring. The default value is 1.0.
Steps Per Pass
Number of steps per single sample. The default value is 10.0.

## Bloom¶

Bloom appears when a picture has elements with a very different brightness. A glowing halo is created around the bright details.

### Activation¶

Activate the Bloom panel under the Render tab.

Use calculation of adaptive average luminance. Enabled by default.
Intensity
Bloom intensity. Set to 1.0 by default.
Blur
Bloom blurriness factor. Set to 4.0 by default.
Edge Luminance
The boundary value of an element’s relative brightness above which the bloom effect appears. Set to 1.0 by default.

## Outlining¶

As a result of the outline glow effect, a luminous colored halo will be displayed around the object.

### Activation¶

The outlining is activated programmatically via API. Different animation models can be applied such as constant glow, fading out glow, pulsatory glow and any other. In order to enable the outlining effect on a certain object, make sure that the Render > Object Selection panel’s Enable property is set to ON or AUTO.

On the Object > Selection and Outlining panel:

Enable Outlining
Permit using the outline glow effect on this object.
Duration
Duration of glow animation, seconds. The default value is 1.
Period
Repeat period of glow animation, seconds. The default value is 1.
Relapses
The number of iterations of glow animation. If zero, animation is repeated forever. The default value is 0.
Outline on Select
Activate glow animation upon selecting the object. In this case the Selectable option must be enabled. In case of a user-defined glow animation model, this option must be disabled in order to avoid conflict.

On the Render > Object Outlining panel:

Factor
When this parameter decreases so does the thickness and the brightness of the halo around the object. The default value is 1.

The Render > Object Outlining settings are taken as default when the glow effect is initiated via API.

## Glow¶

Effect of halo which is observed around emissive objects due to light scattering in the atmosphere and inside the human eye.

### Activation¶

Add a B4W_GLOW_OUTPUT node to a node material. The Enable Glow Materials option on the Render > Glow Materials panel should be set to ON or AUTO.

Intensity of glow obtained through the smaller mask. The default value is 2.0.
Width of glow obtained through the smaller mask. The default value is 2.0.
Intensity of glow obtained through the larger mask. The default value is 2.0.
Width of glow obtained through the larger mask. The default value is 6.0.
Render Glow Over Transparent Objects
Render the glow effect over transparent objects.

## Anti-Aliasing¶

Anti-aliasing is used to reduce undesirable rendering artifacts (poor pixelization).

### Activation¶

Select quality profile using AA Quality menu located on the Render > Anti-Aliasing panel.

• None - disable anti-aliasing,
• Low, Medium, High - enable anti-aliasing with the given quality profile.

Medium profile is used by default.