Acorn's Brush Designer

New in Acorn 1.5, the Brush Designer is a powerful tool to alter existing brushes, and make new ones. Simply draw in the canvas provided, change the settings for the brush, and watch your brush strokes update to use the new settings.

Here's a rundown of what the various options are:

Shape Options

• Size
  This is the width and height of your brush. To make your brush bigger or smaller, this is the setting you'll want to modify.
• Spacing
  Acorn uses a dabbing (also known as stamping) method for its brushes. In essence, a brush stroke is a whole bunch of stamps of the same image over and over again. The spacing option decides how close together those stamps should be.
• Softness
  This option alters the brush stroke to have a softer or harder edge.
• Squish
  Do you want your brush to have a a slight angle to it, like a felt tip pen might have? Use this option to decide how much.
• Rotate
  This will rotate your brush dab to your desired angle.
• Use Image…
  If you have a pre-existing image you'd like to use as for the brush, you can use this button to choose it. Alternatively, the stamp preview will allow you to drag and drop images into it. So you could make a brush pattern in Acorn, and then drag and drop the image into the preview.

Tablet Options

• Faster drawing / less accurate strokes
  When this is turned on, Acorn will throw out some of the data it receives from your tablet in order to perform faster drawing. However, it also means that drawing won't be quite as accurate as you mean when using your tablet. Turn this option on if you have a slower computer, or you aren't happy with the speed of Acorn's drawing.
• Use tablet pressure for opacity
  When this is turned on Acorn will make your brush strokes more or less opaque, depending on the pressure you use with your tablet stylus.
• Use tablet pressure for stroke width
  When this is turned on Acorn will alter your brush strokes to be thicker or thinner, depending on the pressure you apply with your stylus.
• Tablet pressure range
  This slider alters the minimum bound that the pressure sensitive options go to. If you find that there's too much range in the stroke width, you can change this setting to make your brush strokes not quite so skinny.

Misc Options

• Dab opacity
  This is the amount of transparency that your brush will use when drawing. A lower value means it is more transparent.
• Jitter
  This option adds a range of randomness to your brush strokes.
• Brush blending
  Control how the brush strokes are applied to your image. Use Multiply for for a felt tip feeling to it, or Darker if you just want your brush strokes to add darkness to your image.
• Rotate brush
  This will rotate the brush depending on the direction you are drawing. Works great with shapes.
• Color image
  If you are using a custom image for the brush (as setup under the Shape Options), you can turn this on to make your image/brush change its color to whatever you have set from the foreground color well. If you turn this off, Acorn will use whatever colors are in the image for the brush (like with the "Pencil Handle" shape brush).
• Smooth lines
  With this option turned on, Acorn will try and smooth out any edges it finds when drawing (which is especially useful when drawing with the mouse)

A brush with blending set to multiply:


The same brush, with blending set to normal:

Saving a Brush

To save your brush, just type ⌘-S and a sheet will appear asking you for a name for the brush, as well as a category. You can add your brush to an existing category, or create a new one. Custom brushes are saved to your ~/Library/Application Support/Acorn/Brushes/ folder, and you can even exchange your brushes with friends over email, simply by sending them your saved brush from the Finder.