Painting

The core of CGpainter: tools, brush settings, and the modifiers that shape where and how paint lands.

Painting tools

Choose a tool from the tool rail down the left side. They all paint into the active layer's enabled channels.

The painting tools only work on paint layers (where you paint pixels directly) and on masks (paint to reveal or hide a layer). To set up fill layers and procedural masking instead, see Layers and Masks & generators.
The tool rail
ToolKeyWhat it does
BrushBPaint colour / material onto the surface.
AirbrushABuilds up colour gradually while held in place — like a real airbrush.
EraserERemove paint from the active layer.
SelectionSSelect a region to confine painting — see Selection.
FillFFlood-fill a region or UV island in one click.
SmudgePush and smear existing paint along the stroke.
BlendSoften / blend between neighbouring colours.
GradientGDrag to lay a colour gradient across the surface.
EyedropperVPick a colour from the model.

Gradient tool

The Gradient tool (G) lays a multi-stop colour ramp across the surface. Pick the tool, then drag an axis on the model — the drag direction and length define the gradient. It works in the 3D view and the 2D UV view. The gradient stays a live preview until you confirm.

Build the ramp in the Tool Options bar: it holds up to 8 colour stops (click a swatch to recolour it, +/ to add or remove). Choose a gradient Type:

TypeShape
LinearRamp runs straight along the dragged axis.
RadialRamp radiates outward from the start point.
ReflectedStart point is the centre; the ramp mirrors out both ways (a beam).

A per-gradient Blend mode (Normal, Multiply, Screen, Overlay, …) and Opacity control how the ramp combines with what's already on the layer. Save a ramp you like as a Preset (the picker also ships built-ins like Spectrum, Fire, and Ocean; your saved presets are marked with a star and can be deleted).

Press Enter to confirm the gradient (it bakes destructively into the active channel) or Esc to discard the preview.
The Gradient tool preview on the model

Brush settings & channels

This section is about painting on a paint layer. Fill layers and masks aren't painted dab by dab — they're recipe-based (you configure what fills them), so their Properties look different. We cover those in Layers and Masks.

The Properties panel is contextual — what it shows depends on what you have selected. With a paint layer active, it shows the brush settings below, which apply to the Brush, Eraser, and most paint tools.

Brush settings in the Properties panel for a paint layer

Core settings

SettingEffect
SizeBrush radius (how wide the stroke is).
HardnessEdge falloff — soft, feathered edge vs. a hard edge.
OpacityMaximum coverage a single stroke can build up to.
FlowHow much paint each dab deposits (build-up rate).
SpacingDistance between dabs along the stroke.
Quick gesture: Ctrl + right-drag adjusts size (drag horizontally) and hardness (vertically) without leaving the viewport.

Scatter

The Scatter section randomises each dab so a stroke doesn't look mechanical:

ScatterEffect
Size ScatterPer-dab random size reduction (0–1).
Flow ScatterPer-dab random flow reduction (0–1).
Rotation ScatterPer-dab random rotation, ± up to 180° (non-round stamps only).
Position ScatterScatters dab position away from the path (0–1).
Pos. AxisRestrict the position scatter to Both axes, X only, or Y only.
Pos. DistributionUniform or Gaussian spread for the position scatter.
Scatter is baked per-dab as you paint, so undo, replay, and canvas-resize all reproduce the exact same scattered stroke.

Colour

Set the paint colour in the Brush panel's colour picker, or press V to eyedrop a colour straight off the model.

Channels

A stroke writes only into the channels you enable for the brush (the channel mask). Toggle them in the Brush panel — paint Base Color + Normal together, or isolate just Roughness, for example.

Dynamics, stabilizer & smooth

Tune how a stroke feels — how it responds to your pen, how steady it is, and how to soften what you've painted.

The Stroke panel: dynamics, stabilizer, and smooth settings

Brush dynamics

Drive a brush property from an input sensor (like pen pressure), shaping the response with a curve. The Stroke panel has one Dynamics block per drivable property: Size, Opacity, Flow, and Position Scatter. Each block exposes the sensors below; enabling one reveals its curve editor.

SensorDrives the property from…
PressureStylus pressure (0–1).
TiltHow far the pen is tilted from vertical (0 = upright, 1 = laid flat).
SpeedCursor speed (saturates around a brisk painting pace).
DistanceDistance travelled along the stroke.
FadeA built-in fade-out over the start of the stroke.

The Curve remaps the raw 0–1 sensor value before it scales the property — push it up for a fast, snappy response or down for a gentle one. When several sensors are enabled on one property their outputs are combined (Multiply by default); Strength scales the whole effect and the curve's minimum acts as a floor.

Prefer a one-click setup? Use the Stroke Mode dropdown: Inking (pressure → Size only), Painting (pressure → Flow only), Both, Droplet (inverse — small when pressed hard), Constant (ignore pressure), or Custom to use the per-property dynamics above. Zero P Radius keeps a minimum brush size at zero pressure so feather-light touches still register.

Stabilizer

Smooths the cursor path while you draw, for steadier lines. Turn it on with the Stabilizer (Lazy Mouse) checkbox in the Stroke panel.

SettingEffect
RadiusDead-zone in pixels — the cursor must travel this far before the brush follows (the "rubber-band" lag).
StrengthHow much the path lags toward the previous point (0–0.95). Higher = steadier but more rubber-band lag.

The stabilizer is disabled automatically during straight-line drawing so the line stays geometrically exact.

Smooth

Softens / blurs existing paint on the surface (seam-aware). It's a modifier on the Brush / Airbrush, not a separate tool: hold Shift while painting and the stroke blurs the texels it passes over instead of laying down colour.

Set the strength with Shift + mouse wheel — this steps the blur kernel from 1 to 8 (a 3×3 up to a 17×17 box), with a read-out on the cursor. Smooth is resolution-independent, so a stroke blurs the same at any canvas resolution.

Stamps & alphas

An alpha (or stamp) is the shape of the brush footprint — instead of a plain round dab you can stamp a pattern, symbol, or texture.

Procedural shapes

Built-in shapes like circle, square, and hexagon.

Imported alphas

Drag a grayscale image from the Shelf's Alphas tab to use it as the brush footprint.

Screenshot: Shelf ▸ Alphas + a stamped result

Stamp transform

When the footprint is a non-round stamp (Square, Hexagon, or an imported alpha), the Brush panel exposes a Rotation dial and slider (0–360°) to spin it. A round circle is rotation-invariant, so the control is hidden for it. Square, Hexagon, and alpha stamps are placed in screen space along the stroke; the plain circle is a true surface dab.

Mirror, stencil & projection

Modifiers and view aids layered on top of whatever tool you're using — changing where paint lands, or how you see the surface as you work.

The modifiers panel: mirror, stencil, and projection controls

Mirror / symmetry

Reflects your strokes so you paint several places at once — ideal for symmetrical models. Open the Symmetry panel, choose a Type, and pick the Axis (X, Y, or Z). Every dab is copied at emit time, so it works with any tool and survives undo / replay.

The Display section toggles the on-screen guides: Show intersection (the line where the mirror plane cuts the mesh, or the radial axis — on by default), Show plane (the filled mirror plane), Show cursor, and Hide while painting.

GIF: painting with mirror on

Stencil

Projects an image onto the view, and your brush paints its colours through it — perfect for stamping logos, decals, or patterns precisely. The stencil is a screen-space modifier: enable it, then load an image to project.

The stencil shows as an overlay with handles. Drag the body to move it, a corner to scale, and the top handle to rotate (hold Shift to snap). It re-centres, unscaled and upright, when you load a fresh image. While you paint, the overlay hides so it doesn't block the view, then reappears when the stroke ends.

Painting through a stencil is destructive — it projects the image's actual colours onto the surface, not just a mask.
Screenshot: stencil over the model

Perspective / Orthographic

The toggle in the top toolbar switches the camera between perspective (natural depth, the default) and orthographic (parallel projection, no perspective distortion). Orthographic lets you paint straight-on with no foreshortening — useful for precise, flat work.