Create Fluid Mask (CreateFluidMask) - ComfyUI-KJNodes

The Create Fluid Mask node, implemented based on a stable fluid dynamics algorithm, simulates the diffusion process of dye in a fluid by setting multiple inflow points and controlling their physical properties such as velocity and radius.

The Create Fluid Mask node is a tool for generating dynamic fluid effect masks. By simulating fluid motion, it creates a sequence of black-and-white images that change over time and possess a natural sense of flow. This node primarily serves image processing and generation workflows that require dynamic or organic-shaped masks.

Node Functionality

This node is implemented based on a stable fluid dynamics algorithm. It simulates the diffusion process of dye in a fluid by setting multiple inflow points and controlling their physical properties such as velocity and radius. It outputs an image sequence and corresponding mask data with a specified number of frames, width, and height. All parameters can be adjusted within defined integer ranges, and the core calculations rely on mathematical functions from the SciPy library.

Node Parameter Description - Create Fluid Mask

Control Parameters (Parameters)

Parameter Name	Data Type	Required	Default Value	Range/Options	Description
`invert`	BOOLEAN	Yes	False	-	invert (input parameter): Inverts the black and white regions of the output mask. When True, originally white (highlighted) areas become black, and vice versa.
`frames`	INT	Yes	1	1 - 4096 (step: 1)	frames (input parameter): Sets the total number of frames for the generated fluid animation. Range 1 to 4096, step 1.
`width`	INT	Yes	256	16 - 4096 (step: 1)	width (input parameter): Sets the width in pixels for the generated fluid image. Range 16 to 4096, step 1.
`height`	INT	Yes	256	16 - 4096 (step: 1)	height (input parameter): Sets the height in pixels for the generated fluid image. Range 16 to 4096, step 1.
`inflow_count`	INT	Yes	3	0 - 255 (step: 1)	inflow_count (input parameter): Defines the number of "inflow points" in the fluid simulation. Range 0 to 255, step 1.
`inflow_velocity`	INT	Yes	1	0 - 255 (step: 1)	inflow_velocity (input parameter): Controls the velocity intensity of the fluid inflow points. Range 0 to 255, step 1.
`inflow_radius`	INT	Yes	8	0 - 255 (step: 1)	inflow_radius (input parameter): Sets the radius of effect for each fluid inflow point. Range 0 to 255, step 1.
`inflow_padding`	INT	Yes	50	0 - 255 (step: 1)	inflow_padding (input parameter): Controls the minimum distance between inflow points and the canvas edge. Range 0 to 255, step 1.
`inflow_duration`	INT	Yes	60	0 - 255 (step: 1)	inflow_duration (input parameter): Sets the duration (in frames) for which each inflow point continuously generates fluid. Range 0 to 255, step 1.

Output

Parameter Name	Data Type	Description
IMAGE	IMAGE	IMAGE (output parameter): The output fluid simulation image sequence, in grayscale.
MASK	MASK	MASK (output parameter): The mask data corresponding to the image, which can be used to control the processing area of other nodes.

Usage Scenarios

In video generation or image animation workflows, you can use the dynamic masks generated by this node to control the application area of special effects. For example, connecting the output MASK to ControlNet can guide the generation of images with fluid texture characteristics; or using the IMAGE sequence as a dynamic background for compositing with other image layers.

Notes

Please note that higher resolution or frame count settings may significantly increase computation time and memory usage. Additionally, the fluid patterns generated by this node are random; identical parameter settings may produce slightly different results.

Create Fluid Mask Node Source Code Link

The Create Fluid Mask node is from the ComfyUI-KJNodes node package.

Create Fluid Mask(CreateFluidMask)