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Procedural Wetness controls

This page mirrors the order of the panels in 3D Viewport > Sidebar > Wetness. Every comparison changes the named control while holding the rest of the demonstration setup constant. All renders use Max and the poolside city scene shown throughout this guide.

Units and scale

The renders use Blender's default metric scale and a target that is 2 m tall. Distance controls follow the scene's unit display and are scaled proportionally to the selected target's evaluated size.

Regenerate means choose Regenerate Water to see the change. Controls under Water Look update existing add-on materials immediately.

Drops

Small Amount

Default: 900 · Range: 0 or greater (soft maximum 2,000) · Update: Regenerate

Controls the maximum point density used by the live small-drop scatter. Spacing can prevent the requested density from being reached.

Small Amount — 120
120

Small Min

Default: 0.003 m · Range: 0.0001 m or greater (soft maximum 0.02 m) · Update: Regenerate

Sets the smallest visible diameter used for small drops. The add-on sorts Small Min and Small Max if they are entered in reverse order.

Small Min — 0.0015 m
0.0015 m

Small Max

Default: 0.006 m · Range: 0.0001 m or greater (soft maximum 0.02 m) · Update: Regenerate

Sets the largest visible diameter used for small drops. A wider gap between Small Min and Small Max creates more size variation.

Small Max — 0.004 m
0.004 m

Small Height

Default: 0.18 · Range: 0.05–1.0 · Update: Regenerate

Controls small-drop height relative to width. Low values sit close to the surface; high values look rounder and more raised.

Small Height — 0.08
0.08

Big Drops

Default: 1,000 · Range: 0–100,000 (soft maximum 5,000) · Update: Regenerate

Requests up to this many editable hero drops. Masks, spacing, and available surface area can reduce the final count.

Big Drops — 100
100

Big Spacing

Default: 0.01 m · Range: 0 m or greater (soft maximum 0.1 m) · Update: Regenerate

Sets the minimum center spacing between hero drops. Increase it for a cleaner, sparser layout.

Big Spacing — 0.004 m
0.004 m

Big Min

Default: 0.003 m · Range: 0.0001 m or greater (soft maximum 0.05 m) · Update: Regenerate

Sets the smallest radius used for hero drops. The add-on sorts Big Min and Big Max if necessary.

Big Min — 0.0015 m
0.0015 m

Big Max

Default: 0.005 m · Range: 0.0001 m or greater (soft maximum 0.05 m) · Update: Regenerate

Sets the largest radius used for hero drops.

Big Max — 0.004 m
0.004 m

Drop Stretch

Default: 2.0 · Range: 0 or greater (soft maximum 10) · Update: Regenerate

Sets the maximum downhill run multiplier for hero drops and small drops. Slope, water mobility, and random drop state determine how much of that maximum each drop uses.

Drop Stretch — 0.5
0.5

Streams & Flow

Streams

Default: 20 · Range: 0–10,000 (soft maximum 100) · Update: Regenerate

Requests up to this many stream seeds. Spacing, masks, drainage, and the surface shape can reduce the number of valid streams.

Streams — 2
2

Width

Default: 0.008 m · Range: 0.0001 m or greater (soft maximum 0.05 m) · Update: Regenerate

Sets the starting radius of each stream. Merged streams can become wider up to Max Width.

Stream Width — 0.003 m
0.003 m

Length

Default: 90 · Range: 1–1,000 (soft maximum 300) · Update: Regenerate

Sets the maximum number of tracing steps per stream. A stream can stop earlier when it reaches the edge of valid surface flow.

Stream Length — 5 steps
5 steps

Max Splits

Default: 3 · Range: 0–20 · Update: Regenerate

Caps the number of eligible branch paths added across the generated streams. It is a maximum: a split is created only where the two downhill routes are similar enough.

Maximum Stream Splits — 0
0

Split Width

Default: 0.48 · Range: 0.05–1.0 · Update: Regenerate

Scales branch thickness relative to the parent stream and the share of flow taken by that branch.

Split Width — 0.2
0.2

Split Length

Default: 0.2 m · Range: 0.01–2.0 m · Update: Regenerate

Sets how far a generated split may travel over the target.

Split Length — 0.1 m
0.1 m

Water Amount

Default: 1.0 · Range: 0–20 (soft maximum 10) · Update: Regenerate

Sets the amount of water present before the surface-drainage pass. It affects where water remains available for drop and stream sampling; it is not a direct curve-count multiplier.

Water Amount — 0.25
0.25

Surface Flow

Default: 0.22 · Range: 0–1 · Update: Regenerate

Controls how quickly the simulated surface water moves downhill during the drainage pass. Zero preserves the initial distribution.

Surface Flow — 0
0

Hold

Default: 0.08 · Range: 0–1 · Update: Regenerate

Controls pinning: the amount of water that resists drainage at each vertex. Higher values keep more water near its starting area.

Hold — 0
0

Hanging & Airborne

Hanging

Default: 25 · Range: 0–1,000 (soft maximum 100) · Update: Regenerate

Requests up to this many drops hanging from valid stream-end anchors. The result can be lower when the surface does not provide enough separated anchors.

Hanging Drop Count — 0
0

Hang Size

Default: 0.015 m · Range: 0.0001 m or greater (soft maximum 0.05 m) · Update: Regenerate

Sets the maximum radius of hanging drops. Short drops can clamp the radius below this value.

Hanging Drop Size — 0.004 m
0.004 m

Hang Length

Default: 0.025 m · Range: 0.001 m or greater (soft maximum 0.1 m) · Update: Regenerate

Sets the maximum distance a hanging drop stretches from its anchor along Gravity.

Hanging Drop Length — 0.01 m
0.01 m

Airborne

Default: 10 · Range: 0–1,000 (soft maximum 100) · Update: Regenerate

Requests up to this many drops falling free of the surface. Airborne drops use the remaining valid anchors after hanging drops, so their final count may be lower.

Airborne Drop Count — 0
0

Air Size

Default: 0.008775 m · Range: 0.0001 m or greater (soft maximum 0.05 m) · Update: Regenerate

Sets the maximum radius of airborne drops. The chosen fall distance can clamp the actual radius.

Airborne Drop Size — 0.003 m
0.003 m

Fall Distance

Default: 0.08 m · Range: 0.015 m or greater (soft maximum 0.5 m) · Update: Regenerate

Sets the farthest an airborne drop may be placed from its anchor along Gravity. Each drop receives a random distance up to this maximum.

Maximum Fall Distance — 0.02 m
0.02 m

Puddles

Amount

Default: 1.0 · Range: 0–4 · Update: Regenerate

Scales the spread of puddle metaballs around every painted receiver point. Zero disables puddles without deleting the receiver mask.

Puddle Amount — 0.25
0.25

See Masks and puddles for Receiver, Paint, Allow, and Block.

Water Look

Roughness

Default: 0.03 · Range: 0–1 · Update: Immediate

Controls the softness of reflections on free water. Low values create sharp highlights; high values blur them.

Water Roughness — 0
0

Absorption

Default: 0.8 · Range: 0–10 · Update: Immediate

Controls volume-absorption density in free water. Higher values darken thick water more quickly and have little effect on extremely thin droplets.

Water Absorption — 0
0

Contact Sheen

Default: 0.4 · Range: 0–1 · Update: Immediate

Controls the brightness of the thin reflective rim where surface water meets the target. The effect is strongest under grazing or back lighting. The comparison isolates that thin-water material on larger drops so the rim brightness is visible at thumbnail size.

Contact Sheen — 0
0

Small Drop Shine

Default: 0.25 · Range: 0–1 · Update: Immediate

Controls dielectric highlight strength on the small-drop material. Lighting, roughness, and transmission determine how visible the difference is. The comparison uses dark, opaque drops and a fixed highlight light so this single material response remains easy to read.

Small Drop Shine — 0
0

Advanced

Seed

Default: 17 · Range: any integer · Update: Regenerate

Changes the randomized hero-drop, stream, branch, hanging, airborne, and puddle layout without changing their requested amounts. It does not change the small-drop scatter seed.

Random Seed — 7
7

Drop Flatness

Default: 0.12 · Range: 0.02–1 · Update: Regenerate

Controls the cross-section height of big drops. Lower values sit flatter; higher values become rounder and more raised. Hanging and airborne profiles use a related, capped value.

Drop Flatness — 0.05
0.05

Merge

Default: 0.06 m · Range: 0 m or greater (soft maximum 0.2 m) · Update: Regenerate

Sets how close a stream endpoint must come to an accepted stream before the paths join. Zero effectively disables distance-based merging.

Stream Merge Distance — 0 m
0 m

Max Width

Default: 0.03 m · Range: 0.0001 m or greater (soft maximum 0.1 m) · Update: Regenerate

Caps the radius a trunk can reach after other streams merge into it. It has no visible effect when no merge occurs or when the calculated trunk is already narrower than the cap.

Maximum Merged Stream Width — 0.005 m
0.005 m

Gravity

Default: X 0, Y 0, Z −1 · Range: any non-zero direction · Update: Regenerate

Sets the direction used for drainage, drop stretch, stream tracing, hanging drops, airborne drops, and small-drop orientation. Magnitude is normalized; the zero vector is invalid.

Gravity Direction — Down (0, 0, −1)
Down (0, 0, −1)

Procedural Wetness for Blender 5.2