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5. Generalized Lines and Splines

5.1. Diagonal Lines

It is possible to specify diagonal lines or arrows by adding multiple up, down, left, and right modifiers to the line object. Any of these can have a multiplier. To understand the effects, think of the drawing area as being gridded with standard-sized boxes.

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Figure 5-1: Diagonal arrows (dotted boxes show the implied 0.5-inch grid)

5.2. Multi-Segment Line Objects

A “line” or “arrow” object may actually be a path consisting of any number of segments of varying lengths and directions. To describe a path, connect several line or arrow commands with the keyword then.

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Figure 5-2: line right 1 then down .5 left 1 then right 1

5.3. Spline Objects

If you start a path with the spline keyword, the path vertices are treated as control points for a spline curve fit.

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Figure 5-3: spline right 1 then down .5 left 1 then right 1

You can describe many natural-looking but irregular curves this way. For example:

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Figure 5-4: Two more spline examples

Note the arrow decorations. Arrowheads can be applied naturally to any path-based object, line or spline. We’ll see how in the next section.


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