unreal.CompositePassDilation

class unreal.CompositePassDilation(outer: Object | None = None, name: Name | str = 'None')

Bases: CompositePassBase

Morphologically dilates or erodes selected channels of the layer input by a configurable pixel radius. Used to grow or shrink mattes before downstream compositing operations.

C++ Source:

  • Plugin: Composite

  • Module: Composite

  • File: CompositePassDilation.h

Editor Properties: (see get_editor_property/set_editor_property)

  • carry_rgb_with_alpha (bool): [Read-Write] When Alpha is selected, the alpha-winning neighbor’s RGB is copied into any color channels that aren’t explicitly in the Channels mask, so mattes grow/shrink visibly. Disable for strict “alpha only” semantics (RGB untouched).

  • channels (int32): [Read-Write] Channels the operation reads and writes. Defaults to all channels so a fresh Dilation Pass affects RGB and alpha together.

  • display_name (str): [Read-Write] The display name of the pass

  • is_enabled (bool): [Read-Write] Whether or not the pass is active.

  • size (int32): [Read-Write] Signed size: negative = erode (shrink), positive = dilate (expand), 0 = identity (pass disabled).

  • threshold (float): [Read-Write] In standard opacity space (0 = transparent, 1 = opaque): a channel’s value is treated as “off” at or below this threshold and “on” above it. Only used when Use Threshold is enabled.

  • use_threshold (bool): [Read-Write] When true, the operation only fires on pixels that are essentially off (at or below a small epsilon), thus only affecting matte edges.

property alpha_threshold: float

‘alpha_threshold’ was renamed to ‘threshold’.

Type:

deprecated

property carry_rgb_with_alpha: bool

[Read-Write] When Alpha is selected, the alpha-winning neighbor’s RGB is copied into any color channels that aren’t explicitly in the Channels mask, so mattes grow/shrink visibly. Disable for strict “alpha only” semantics (RGB untouched).

Type:

(bool)

property channels: int

[Read-Write] Channels the operation reads and writes. Defaults to all channels so a fresh Dilation Pass affects RGB and alpha together.

Type:

(int32)

property size: int

negative = erode (shrink), positive = dilate (expand), 0 = identity (pass disabled).

Type:

(int32)

Type:

[Read-Write] Signed size

property threshold: float

a channel’s value is treated as “off” at or below this threshold and “on” above it. Only used when Use Threshold is enabled.

Type:

(float)

Type:

[Read-Write] In standard opacity space (0 = transparent, 1 = opaque)

property use_threshold: bool

[Read-Write] When true, the operation only fires on pixels that are essentially off (at or below a small epsilon), thus only affecting matte edges.

Type:

(bool)