Brush & freehand drawing

The brush is the foundation of freehand drawing in Formo — and unlike a raster brush, what it produces is a real vector shape from the moment you lift the pen, not a bitmap you trace over afterward.

The draw mode toolbars

Switching to draw mode (Ctrl+2) brings up two separate floating panels: the main tool panel on the left, and a compact action bar that appears lower on the screen. Both can be dragged by their handle (the small dotted grip on the left edge) to reposition them wherever's comfortable.

The main tool panel

Five rows of tools, top to bottom, each occupying a fixed position:

- The Pointer is draw mode's plain selection tool. Click a stroke to select it, and its nib, size, smoothing, and fill properties populate the panel below. It's the tool you return to after most other actions, the same role the Selection tool plays in Adobe Animate.

Select Rectangle is a marquee tool with its own flyout holding three variants. Click its arrow to reach them:

- Free-form Selection: draw an arbitrary lasso shape by hand instead of a fixed rectangle.

- Paint Selection: "paint" a selection area with a brush-like gesture rather than dragging one boundary.

- Bucket Selection: click once inside an enclosed region, and that whole region becomes your selection, the same gap-tolerant logic the paint bucket uses for filling, applied to selecting instead.

These are the "types of rectangles" worth knowing about: it's not variations on a rectangle shape itself, but three different ways of defining a selection area, grouped under the one Select Rectangle slot.

Paint Normal paints on top of whatever's already there — the standard brush behavior, and the one you'll use most.

Paint Behind paints underneath existing artwork on the same layer instead, so you can add something behind a line without disturbing the line itself.

Paint Fills only affects fill areas, letting you recolor freely without ever touching the linework.

Paint Inside constrains your stroke to the region you started inside, so it won't spill into a neighboring area even if you drag past its edge.

Erase removes ink instead of adding it, using the same nib and size settings as painting.

Paint Bucket fills an enclosed region with one click, tolerating small gaps in the linework rather than leaking through them.

Sculpt reshapes existing ink — push, twirl, pinch, or bloat — rather than adding new paint at all.

Below the divider is the contextual section, which changes based on whichever tool above is active: the nib picker and live preview, Size and Smooth, Brush options and Dynamics, and a Fill swatch with recent colors. Select Pointer or a selection tool, and this whole section collapses: there's nothing to configure until you're painting or sculpting.

The actions bar

A separate, compact strip appears lower on the screen: one-tap versions of the actions you'd otherwise reach by keyboard, specifically there for stylus and touch use (though it's available with a mouse too, any time you're in Draw mode).

- New Layer: creates a new layer to draw into. In Draw mode, "layer" specifically means a brush layer: its own independent surface with its own timeline, so drawing on a new layer never touches what's on any other layer, and each one can hold and animate its own frames completely separately. This is the same underlying concept covered in the Frames guide's "independent timelines" section, just reached here with one tap instead of the layers panel.

- Add Keyframe (F6), Hold Frame (F5), Empty Keyframe (F7): the same three actions covered in depth in the Frame-by-frame animation guide, available here without needing a physical keyboard.

- Undo and Redo: the same Ctrl+Z / Ctrl+Shift+Z actions, as buttons.

Having the full F5/F6/F7 triad plus layer creation and undo/redo all reachable by tapping, with no keyboard required, is what makes serious frame-by-frame work possible on a tablet or a stylus-driven display, and comfortable to do all day.

The brush tool: your first stroke

Paint Normal — the standard brush — is the one you'll use most, and it's usually the default active tool when you enter Draw mode.

Drawing a stroke. Click and drag anywhere on the canvas. The line that appears follows your gesture in real time, already showing whatever taper your current pressure settings produce. Release, and the stroke commits immediately: selected, and with its own properties (nib, size, smoothing, fill) available in the contextual panel below the tool rows.

What you're actually creating. A brush stroke isn't a flattened image. It's built from two things kept together: your raw input samples (the actual path, pressure, and tilt values your hand produced) and a derived outline (the filled shape that ink turns into on screen). Keeping both is what makes everything in the rest of this section possible: editing after the fact, converting to a plain vector path and back, direct point editing. None of it would work if a stroke were just a picture of ink.

With Paint Normal active, the contextual panel below the tool rows shows a nib picker (Ellipse, Diamond, Rect) with a live preview, plus Size and Smooth values for the stroke itself. Below that, Brush options hides four settings you set once (Min Size, Stabilize, Pressure mode, Pull to end), and Dynamics opens the full binding system for wiring inputs like pressure or tilt to a stroke's size, ratio, or angle. A Fill swatch with your recent colors sits at the bottom for picking what you're painting with.

Pressure and tilt: drawing with a stylus

On real pressure-sensitive hardware, Formo reads your actual pressure, tilt, and barrel twist continuously as you draw, the signal your hardware reports.

Pressure. Press harder, and the stroke widens; ease off, and it thins — directly, in real time, not applied as a filter afterward. How much of an effect pressure has is itself adjustable (see Min Size below), so you can dial a stylus from fully expressive down to nearly flat if that's the feel you want.

Tilt and twist. Tilting the pen changes the effective angle the nib sweeps at, and rotating the pen along its own barrel (twist) is read too, on hardware that reports it. Combined with an angled nib (covered in the next section), this is what produces broad-edge calligraphic variation — the same physical logic as tilting a real chisel-tip pen.

On a mouse, pressure is synthesized. A mouse reports no pressure at all, so Formo fakes a believable one, switchable between three modes in the toolbar (Brush option):

- Vel: width responds to how fast you're moving (faster = thinner).

- Decay: a softer, decaying taper based on velocity.

- Const: flat, constant width regardless of speed.

Min Size. A floor under how thin your lightest pressure is allowed to make a stroke, from 0% (a feather-light touch can taper to nearly nothing) up to 100% (pressure has no thinning effect at all: every touch produces full width). This is the control that determines how expressive pressure feels overall.

Stabilize. A stroke-smoothing mechanic, not just a post-hoc filter: think of it as your ink trailing behind the pen tip on a short leash, up to 40 screen pixels long. A longer stabilize distance damps out hand jitter more aggressively, at the cost of the ink lagging slightly behind fast motion. Set it to 0 to turn it off entirely and draw raw.

Pull to end. With the stabilizer on, the trailing ink normally stops wherever it was lagging to when you lift the pen. This option pulls it the rest of the way to your actual final pen position instead, so a stabilized stroke still ends exactly where you lifted, not short of it.

Choosing a nib: ellipse, rectangle, diamond

The brush isn't a point sweeping along your gesture. It's a small shape doing the sweeping, and that shape's identity is what gives a stroke its character.

Three nib shapes, selectable from the picker above the nib preview: ellipse, diamond, and rect. A perfectly round nib is the Ellipse nib at a 1:1 width ratio (its default), which is why there's no separate circle button; it's already there when you leave Ellipse untouched.

Width ratio. Push an elliptical or rectangular nib's ratio away from 1:1, and it flattens: no longer round, but an oval or a flattened rectangle. Nothing else changes about how it sweeps; the shape itself is just less symmetric now.

Angle. A flattened nib held at an angle is where calligraphic variation comes from: thick where the stroke crosses the nib's wide axis, thin where it crosses the narrow one, the same physical logic as a broad-edge calligraphy pen. This angle is a live, adjustable parameter, not locked to however the nib started.

The live preview. The nib picker shows a checkered swatch with your current nib rendered directly on it — shape, ratio, and angle all visible at a glance, updating the instant you change any of them, so you're never guessing what a setting will look like on the canvas.

Next up — Reshaping a brush stroke: three different ways to change ink you've already put down.