Brush Manipulation

Each of the display methods allow the user to directly manipulate the brush. A summary of manipulation techniques for each display method follows:

• Scatterplots - The brush coverage on the scatterplot display is represented by a series of rectangular boxes, one for each scatterplot. The boxes represent the range of points that the brush covers for the two dimensions of a particular scatterplot. Each of these boxes may be manipulated using the mouse. The left mouse button can be used to resize the brush - dragging either a corner or edge of one of the rectangular boxes will alter the brush shape. The middle mouse button may be used to recenter the brush - dragging the box with the middle mouse button pressed will move the brush to the cursor position.
• Glyphs - The brush coverage is not displayed in the glyph view. The brush may be recentered by clicking on a glyph with the left mouse button. The brush will change location to be centered around the selected point. This is useful for finding glyphs that are similar in shape to an existing glyph.
• Parallel Coordinates - The brush coverage on the parallel coordinate display is represented by a shaded region that spans all the dimensions. The shaded region along an axis represents the range of points that the brush covers along that axis. Brush manipulation in this display works similarly to the scatterplot display. Dragging the brush with the left mouse button will resize the brush while dragging with the middle mouse button will recenter the brush.
• Dimensional Stacking - Brush coverage in this display is shown by shading all the bins that are contained by the brush. Brush manipulation in this display works similarly to the glyph display. Clicking on a point will recenter the brush to that point.