The Paint Brush Tool lays down pixels on the page, creating strokes with antialiased edges. This creates a natural transition between the stroke and the surrounding pixels.
Its variable width lines can be controlled either by velocity—most useful when drawing with touch—or by pressure—for use when drawing with a pressure-sensitive device like the Pencil.
Other brush-based tools use similar settings to control the appearance of the applied pixels, although there may be slight variations.
Most brushes use a soft, round brush as their default. Alternative styles can be selected from the Brushes Studio.
Settings
The following settings can be adjusted from the context toolbar:
Width—the brush (stroke) size in pixels.
Opacity—how see through the brush is.
Flow—how fast the pixel brush effect is applied (1% is very slow, 100% is immediate).
Hardness—how hard the edges of the pixel brush are. The brush appears softer as the percentage decreases.
More—tap to display the Brushes dialog to access advanced brush settings.
Protect Alpha—when enabled, you are not able to paint on the current layer's transparent regions.
Color—displays a pop-up menu for selection of a brush stroke color.
Force Pressure—Toggle to control brush size with pressure if using a pressure-sensitive device. This overrides brush defaults.
Wet Edges—builds paint up along the edges of your pixel brush stroke, producing a watercolor effect.
Stabilizer—enables stroke stabilization using either a Rope stabilizer or Window stabilizer mode; the former drags the stroke end by a 'rope' to smooth the stroke but lets you introduce sharp corners at increasing rope Length (radius) values by redirecting the slackened rope; the latter will smooth the stroke by averaging sampled input positions within a Window whose size is configurable.
Symmetry—when the Lines setting is set to greater than 0, repeats the brush stroke around a number of axes (defined by the value). The center axis point can be repositioned by dragging it.
Mirror—with symmetry enabled, causes brush strokes to be mirrored along the X and Y axis.
Lines—with symmetry enabled, defines the number of axes around which the brush stroke will be repeated.
Locked—when enabled, prevents the symmetry line from being moved.