📖 GroomFlow Pro Add-on Guidebook

Welcome to GroomFlow Pro
Welcome to the official documentation and user guide page for GroomFlow Pro.
Learn how to maximize your workflow efficiency using this advanced guide-driven asset.

🚀 Key Features Guide

Guide-Based Strand Generation
Creates dense hair strands from a lightweight guide curve workflow without the performance limitations of traditional systems.
Built around a guide-to-strand generation pipeline, allowing artists to design clean guide curves while automatically generating large amounts of production-ready strands.
Surface-Locked Strand Distribution
Fixes the issue where traditional duplication setups cause strands to float above the surface or clip through the mesh, especially around eyebrows, beards, eyelashes, and high-curvature facial areas.
Solves this problem with a BVHTree-powered surface projection system that continuously snaps generated strand roots directly onto the target mesh.
Results in a stable, surface-locked groom where every generated strand remains accurately attached to the skin without unwanted gaps, floating roots, or penetration issues.
Optimized Production Workflow
Keeps guide curves completely separated from generated output strands, providing a clean and non-destructive grooming workflow.
Mirrors modern professional grooming pipelines while maintaining a simple Blender-native workflow for character hair, eyebrows, facial hair, fur, and Unreal Engine groom preparation.
Designed to maximize visual fidelity while reducing manual cleanup and correction work during production.

🛠 Installation Guide

Before starting the workflow, make sure to set up the add-on correctly by following these steps:

Download
Get the latest version of the GroomFlow_Pro add-on file ready.
Installation
Install and activate the program within Blender preferences.
Follow the general Blender add-on installation guide.
Install Essential Extensions
Go to the Extensions menu inside the add-on preferences.
Click 'Install' on the recommended base extensions to unlock full functionality.
Preferences
Adjust the options to fit your specific workspace layout.

1. Global Scale Calibration

Target Base Scale
Sets the global base scale factor for all generated hair guide curves.
Prevents hair from appearing too small or large due to scene units or character mesh scale differences.
Adjusts the value based on the default 1.0 to uniformly control the scale of all guide curves.

2. Process Control Buttons

Generate Hair Curves
Executes the 50% length blending algorithm to generate actual hair curves on the surface.
This is the final output button used after completing all setups.
Prevents bald spots in weight 0 areas, guaranteeing a minimum of 50% base length.
Go to Weight Paint Mode
Instantly switches the selected mesh into 'Weight Paint Mode'.
Entry point to check and manually brush dense zones (Red) or short zones (Blue).
Eliminates menu navigation, allowing direct map tweaks within the creation workflow.
Smooth Weights Gradient
Smooths out the boundaries of the designated weight map into a soft gradient.
Sharp transitions cause abrupt length changes that look unnatural.
Expands the transition zone, ensuring a smooth length gradient from 100% to 50%.

Warning

Never Modify Properties After Editing Curves
NEVER change the property control values (Density, Length, etc.) in the panel after manually editing or sculpting the generated hair curves.
Changing any value forces the algorithm to recalculate and respawn the hair from scratch, completely wiping out your custom sculpt and guide edits.
Enforce Lock Feature in Sculpt Mode
Always activate the 'Lock' feature before entering Sculpt Mode to protect your custom hair groom data.
The Lock feature acts as a crucial safety mechanism to prevent accidental parameter tweaks from vaporizing your manual editing progress.

3. Generation Options

Replace Existing Hair
Automatically deletes and overwrites previous hair curves in the active layer when generating new ones.
Unchecking this option preserves existing hair, allowing you to layer and stack new curves on top.
Generate on Vertices
Snaps and generates hair guide curves precisely on the vertices of the mesh instead of the face areas.
Useful for low-poly assets or specialized grooms that require perfectly aligned hair placement based on vertex layouts.

4. Hair Settings & Property Controls

Min Length
Sets the minimum length limit for hair generated in the lowest weight areas (0.0).
Lower values shorten hair in blue areas, guaranteeing 50% of the maximum length based on the current algorithm.
Max Length
Sets the maximum length for hair generated in the highest weight areas (1.0).
Functions as the baseline value determining the hair length in key zones painted in red.
Guide Density
Controls the total target count of hair guide curves to be generated on the mesh surface.
Higher numbers spawn denser guides, determining the overall volume and density.
Spawn Radius
Controls the random dispersion radius around the vertices where each guide curve is generated.
At 0.0, it precisely snaps to the surface; increasing the value spreads the spawn positions wider.
Weight Threshold
Sets the minimum threshold cutoff filter of the weight map for hair generation.
Dropping below 0.01 ignores weights to spawn uniformly; raising it cuts off zones below the value.
Strand Resolution
Specifies the number of segments (points) and resolution making up a single hair curve.
Higher values result in smoother and more flexible curves but impact calculation and viewport performance.

5. Thickness & Noise Settings

Min Root Thickness
Globally sets the minimum thickness for the root section of the guide curves.
Used as the lower boundary reference when expressing fine or thin hairs.
Max Root Thickness
Globally sets the maximum thickness for the root section of the guide curves.
Used to define coarse hair or thick foundational guidelines.
Tip Thickness
Adjusts the thickness of the hair ends corresponding to the absolute tip of the guide curves.
Typically set near 0.0 to create a tapering effect that sharpens toward the end.
Frizz Noise Strength
Controls the global noise deformation strength that adds a curly or frizzy feel to the hairstyle.
Increasing the value deviates from straight hair to express an irregular, naturally messy silhouette.

6. Hair Style Nodes Stack

Add Clump
Adds a Clump node to the stack, causing hair strands to gather together around the generated guides.
Used to form hair clumps, creating a more realistic and volumetric hairstyle look.
Add Interpolate
Adds an Interpolate node to the stack, generating filled-in strands between the guide curves.
Drastically increases the overall volume and density of the final hair while maintaining the guide shapes.
Add Curl
Adds a Curl node to the stack, applying a circular, permed wave effect along the guide lines.
Essential for implementing wavy textures or tightly coiled, curly hairstyle aesthetics.
Add Frizz
Adds a Frizz node to the stack, introducing irregular and micro-vibrations across the strands.
Adds a naturally unkempt texture or creates a frizzy effect where hair sticks out in all directions.
Add Braid
Adds a Braid node to the stack, weaving multiple hair strands together into a braided pattern.
Precisely develops stylized, rope-like braids or traditional braided hairstyles.
Add Duplicate
Adds a Duplicate node to the stack, multiplying the existing curves with a structural offset.
Quickly layers hair or amplifies volume as a batch without disrupting the original data flow.

7. Realtime Simple Children

Active Layer
Displays the name of the currently active hair layer receiving the realtime children calculation.
Clarifies and locks the target layer to prevent conflicts when multiple hair systems exist.
Target Object
Specifies the target base mesh (scalp or character body) where the guide curves will bind.
Uses the eyedropper tool to directly select and bind the target mesh from the viewport.
Bind Children Engine
Connects and activates the realtime children acceleration engine between the mesh and hair layer.
Clicking this to complete the binding unlocks and links the sub-property sliders below.
Child Count
Sets the number of child strands to be generated and duplicated around each parent guide curve.
Key parameter for maximizing hair volume in realtime while preserving viewport performance.
Child Point Resolution
Specifies the number of points and resolution making up a single generated child strand.
Higher values result in smoother child curves but increase the realtime viewport calculation load.
Radius
Controls the random dispersion radius where child strands spread around the parent guide curve.
Smaller values bundle the strands tightly, while higher values spread them wider around the parent.
Length Min
Sets the minimum length ratio of child strands relative to the parent guide curve length.
Dropping below 1.0 introduces randomly shorter hairs among the children for a natural look.
Length Max
Sets the maximum length ratio of child strands relative to the parent guide curve length.
Adjusts the value to express stray hairs sticking out past the parent or layered hair styles.

8. Snap Settings (Geometry Nodes Precision Snap)

Object
Specifies the target mesh where the roots of the hair guide curves will precisely snap and bind.
Uses the eyedropper tool to select the scalp or body object as the reference surface for snap calculations.
Add Snap
Applies a precision snap system based on Geometry Nodes, overcoming the limitations of Blender's native snapping.
Ensures hair roots wrap perfectly onto the surface in realtime without lifting or clipping, even during mesh deformations (simulations, shape keys, etc.)

9. Unreal Engine Pipeline & Expert Synergy Workflow

Finalize your asset data blocks and prepare your grooms for cinematic export integration.

* Global Scale Calibration (The Target Base Scale Control) * Blender and Unreal Engine handle FBX/Groom world scale matrices completely differently. * Often causes imported hairstyles to explode into giant sheets or shrink into microscopic pins upon export. * Procedural Pre-Baking Calibration: * Instead of unreliably changing the raw Blender Unit or risking matrix artifacts during asset export, adjust the Target Base Scale slider to calibrate your groom dynamically. * Flawless Pipeline Target: * Keep it at 1.00 for standard Blender rendering setups. * Set it precisely to your target engine scaling coefficient before running ultimate simulation exports. * Enforces an absolute transformation sync into Unreal Engine 5.7+ New Dataflow system without altering the core mesh scales.

* Professional GroomForge Pro Synergy * Exporting hair meshes can be tricky due to world matrices mismatches across different software spaces. * Seamless Matrix Synchronization: * When paired with the GroomForge Pro add-on, your separated guide and child strand layers bypass all transformation conversion issues entirely. * Ensures a 100% flawless, automated import layout into Unreal Engine's native Groom asset system without manual repositioning.

* Performance Tip (Resolution Management) * Optimize your setup dynamically to maintain professional-grade viewport reactivity while working on dense hair grooms. * Real-time Efficiency: * Lower the Strand Resolution down to 4 or 6 while designing massive hairstyles to maximize your viewport FPS smoothness. * Simply bump it back up to 12 right before rendering final frames in Cycles or executing your absolute groom exports to Unreal Engine.