PageStream - Documents:Drawing Paths

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Drawing Paths

A path is a series of any number of line and curve segments. It is called a path because an imaginary pen follows a path to draw the lines and curves. A path with two points would have one segment connecting them, a path with three points would have two segments, and so on.

PageStream uses Bezier curves to generate smooth curves. Each curve has two Bezier control points which define the shape of the curve. Each control point is represented by a round curve handle.

Points are connected by two types of joins:

1. Smooth joins are points that lie on a straight line between their two curve handles. The curve segments connected to a smooth join form a continuous curve.

2. Corner joins are points that connect a curve to a line, two curves that are not continuous, or two lines.

Paths can be either open or closed. Open paths are a series of segments with two end points that are not connected. Closed paths are a series of segments without endpoints; the first and last points are the same.

Setting the current point

Select the ''Pen'' tool to begin drawing a path. The mouse pointer will change to a crosshair shape. Now you must establish which point you will add line and curve segments to. You can set the current point by starting a new path or by extending an existing open path.

Drawing Crosshair Pointer

To start a new path: Position the crosshair at the desired start point of the new path and click the mouse. A point handle will appear to indicate that this is now the current point.

To extend an existing open path: Position the crosshair over the endpoint of a path. A handle will appear when you are within range of an endpoint. Click the mouse button to set this as the current point.

Drawing line segments

To draw a line segment from the current point, position the crosshair at the end of the new segment and click the mouse button. The new point will now become the current point. If you hold down Shift before clicking the mouse, PageStream will constrain the line to horizontal, vertical or 45° line segments.

Note: When drawing a line segment after a curve segment, you must click on the current point before drawing the line. This is because a curve handle for this segment was placed with the previous curve. Clicking on the current point will retract this curve handle and prepare for drawing a line segment.

Drawing curve segments

To draw a curve segment from the current point to another point:

1. Drag out the first curve handle.

Position the crosshair over the current point. The handle will change to indicate that you are within range. Press and hold the mouse button. Drag the mouse in the direction of the curve to drag out the first curve handle.

Note: Hold down Option (Alt) as you drag out the curve handle if you are connecting to an existing segment (like the above example) and you want a smooth join; otherwise you will get a corner join.

2. Drag out the second curve handle.

Now move the crosshair to the desired position of the curve. Click, then drag away from this position to shape the curve. Release the mouse button when the curve is the desired shape.

Note: Hold down Control as you drag out from the end of the curve to drag out the second curve handle of the current segment instead of the next segment's first curve handle. If you want to connect the curve with a corner join instead of a smooth join, hold down Option (Alt) before drawing the curve segment.

3. Continue the path.

The first curve handle of the next curve segment is automatically placed to create a smooth join. If you want to continue by adding a curve connected by a smooth join, just repeat step 2.

If you want to continue by adding a curve connected by a corner join, repeat from step 2, but hold down Option (Alt) before drawing the new curve segment.

If you want to continue by adding a line, click on the current point to retract the next curve handle and then draw a line segment.

The following illustration shows the procedures and the options you have as you draw curves with the ''Pen'' tool:

Ending and closing a path

You can leave a path open or closed when you end it. Ending a path without closing it will leave two unattached endpoints. Closing the path will make it a continuous series of segments.

To close a path: Move the crosshair over the other endpoint and click. If you were drawing a line segment, the path would be closed with a line. If you were drawing a curve segment, the path would be closed with a curve connected to the endpoint by a corner join. To close the path with a curve tangent which is tangent to the first segment at the endpoint, move the crosshair over the other endpoint and drag out a curve handle.

To end a path without closing it: Press the Esc key or the space bar, press the right mouse button, or select a tool from the ''Toolbox''.

Drawing freehand paths

Freehand paths are identical to regular paths once you have finished drawing them, but they are drawn in a very different way. The ''Freehand'' tool allows you to sketch out your ideas and then PageStream smooths your sketch. You do not need to set a current point or worry about endpoints and handles like you do with the ''Pen'' tool.

To draw with the ''Freehand'' tool: Select the ''Freehand'' tool. The mouse pointer will change to a crosshair shape. Position the mouse pointer at the desired start point. Drag the mouse to draw a path. Release the mouse button to end the path. When you release the button, PageStream will smooth the path.

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