Expression Settings

Corel Painter lets you control brush effects along the stroke based on a number of real-time input factors. For example, many brushes vary their Opacity or Size in response to changes in stylus pressure. This is merely their default setting. You can use the Expression settings on the Stroke Designer page to vary these effects in response to other factors, like stroke direction or velocity.

Expression settings are linked to individual controls on the Stroke Designer page. These are: General, Size, Angle, Well, Random, Impasto, Airbrush, and Liquid Ink.

To choose an Expression setting

1. On the Stroke Designer page of the Brush Creator, click a control that contains Expression settings.
2. Choose one of the following options from the Expression pop-up menu:

• None - applies no adjustment to the brush feature
• Velocity - adjusts the brush feature based on the dragging speed. Dragging quickly will minimize the setting; dragging slower increases it.
• Direction - adjusts the selected brush feature based on the direction of the stroke
• Pressure - adjusts the brush feature based on stylus pressure. Greater pressure increases the setting for that brush feature.
• Wheel - adjusts the brush feature based on the wheel setting on an airbrush stylus, specifically the Intuos Airbrush stylus. The maximum value is set when the wheel is pushed all the way forward. The minimum is set when the wheel is pushed all the way back.
• Tilt - adjusts the brush feature based on the angle of the stylus from the tablet. For example, when the stylus is perpendicular to the tablet, Tilt =0.
• Bearing - adjusts the brush feature based on the direction in which the stylus points
• Source - adjusts the brush feature based on the luminance of the clone source. Higher luminance (closer to white) increases the setting for that component-for example, a wider stroke.
• Random - adjusts the brush feature at random
• Sequential - applies only to Rank 2 or 3 Image Hose brushes. When enabled, this feature picks out nozzles from the index, in order.

3. If you like, enable the Invert check box beside the Expression pop-up menu to reverse the effect of the Expression setting.

• Not all stylus models convey tilt or bearing information.

Direction

The Direction slider below the Expression pop-up menu adjusts the angle value of the Direction controller. The angle value represents the direction to which the Controller responds. For instance, when the Controller is set to direction, this setting controls at what angle a brush stroke narrows or widens, particularly useful for calligraphic effects.

To set controller direction

1. On the Stroke Designer page of the Brush Creator, click a control that contains Expression settings.
2. Choose Direction from the Expression pop-up menu.
3. Drag the Direction slider until the desired angle is achieved for controller behavior.