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.
| Tool | Key | What it does |
|---|---|---|
Brush | B | Paint colour / material onto the surface. |
| Airbrush | A | Builds up colour gradually while held in place — like a real airbrush. |
Eraser | E | Remove paint from the active layer. |
Selection | S | Select a region to confine painting — see Selection. |
Fill | F | Flood-fill a region or UV island in one click. |
Smudge | — | Push and smear existing paint along the stroke. |
Blend | — | Soften / blend between neighbouring colours. |
Gradient | G | Drag to lay a colour gradient across the surface. |
Eyedropper | V | Pick 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:
| Type | Shape |
|---|---|
| Linear | Ramp runs straight along the dragged axis. |
| Radial | Ramp radiates outward from the start point. |
| Reflected | Start 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).
Brush settings & channels
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.
Core settings
| Setting | Effect |
|---|---|
| Size | Brush radius (how wide the stroke is). |
| Hardness | Edge falloff — soft, feathered edge vs. a hard edge. |
| Opacity | Maximum coverage a single stroke can build up to. |
| Flow | How much paint each dab deposits (build-up rate). |
| Spacing | Distance between dabs along the stroke. |
Scatter
The Scatter section randomises each dab so a stroke doesn't look mechanical:
| Scatter | Effect |
|---|---|
| Size Scatter | Per-dab random size reduction (0–1). |
| Flow Scatter | Per-dab random flow reduction (0–1). |
| Rotation Scatter | Per-dab random rotation, ± up to 180° (non-round stamps only). |
| Position Scatter | Scatters dab position away from the path (0–1). |
| Pos. Axis | Restrict the position scatter to Both axes, X only, or Y only. |
| Pos. Distribution | Uniform or Gaussian spread for the position scatter. |
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.
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.
| Sensor | Drives the property from… |
|---|---|
| Pressure | Stylus pressure (0–1). |
| Tilt | How far the pen is tilted from vertical (0 = upright, 1 = laid flat). |
| Speed | Cursor speed (saturates around a brisk painting pace). |
| Distance | Distance travelled along the stroke. |
| Fade | A 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.
Stabilizer
Smooths the cursor path while you draw, for steadier lines. Turn it on with the Stabilizer (Lazy Mouse) checkbox in the Stroke panel.
| Setting | Effect |
|---|---|
| Radius | Dead-zone in pixels — the cursor must travel this far before the brush follows (the "rubber-band" lag). |
| Strength | How 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.
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.
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.
- Mirror symmetry — reflects each stroke across the chosen axis plane. The plane passes through the mesh's bounding-box centre; use the Axis position offset for that axis to slide the plane (Reset offset re-centres it).
- Radial symmetry — spins copies of the stroke around the axis. Count (1–64) sets how many copies, and Angle span (1–360°) sets how far they spread. For radial, the two perpendicular offsets position the axis line. Flip alternating copies is available.
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.
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.
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.
Brush
Eraser
Selection
Fill
Smudge
Blend
Gradient
Eyedropper