linear_dim_icon.png Linear Dimension

This tool creates a linear dimension from two clicked points or a selected segment. To generate a linear dimension from two points, click the first point in the model window. Make sure not to locate the mouse over a linear segment, as this will create the dimension from the segment (see below). After the first point is clicked, move the mouse to the location of the second point. The dimension value will be shown. Click the second point. Now the dimension text will be offset from the two clicked points. Click a third time to finish. Note, that this method works best when object snapping is on, which will cause the clicked points to be located exactly on a point of an existing object. However, it is not necessary to click on object points. A linear dimension can also be created from imaginary points anywhere on the reference plane.


To create a linear dimension from a segment, select a straight segment. As soon as the segment is picked, the dimension text is offset as described above.


While clicking points or selecting the segment, the input plane is automatically adjusted to the face over which the mouse is located. This is the same mechanism that occurs when drawing shapes. Dimensions are displayed on a plane and the plane active after selection of the first point or segment will be the one used for the dimension. It is a good practice to move the mouse around until the desired plane is shown, then lock the plane using the f5 key or the context menu. Subsequent clicks will no longer switch the plane. This is illustrated below.


Houses Example
Generating a dimension: (a) Choose and lock the plane.
(b) Click two points and extrude the dimension text on the plane.



Linear dimensions can be generated parallel to the clicked points/selected segment or parallel to the x or y axis of the current plane, as shown below. When extruding the dimension text, color coded guide lines are shown which indicate these three directions. Moving the mouse close to one of the three guides will change the extrusion to that direction.


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Types of linear dimensions: (a) parallel to the points,
(b) parallel to the x axis, and (c) parallel to the y axis.



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The Tool Options palette for the Dimensions.

After the dimension text has been extruded, the dimension is shown in the result highlight color. It is now possible to edit the parameters of the object through the Tool Options palette or by using the on screen controls, as with other objects. The Tool Options palette contains the following parameters:


Style: Select a dimension style from the menu or select Edit Styles... at the bottom of the menu to create new or edit existing styles.


Alignment: Select the desired alignment from the menu. If the dimension style shown in the Style menu above uses the Aligned With Dimension option, five alignments are available (see more details in the Dimension Styles section later on). If the style uses the Horizontal On Screen option, three alignments can be chosen. Examples of the alignments are shown in the figures below.


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Alignment options for Aligned With Dimension styles: (a) At Start, (b) Center Inside,
(c) Center, (d) Center Outside, and (e) At End.



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Alignment options for Horizontal On Screen styles: (a) At Start, (b) Center, and (c) At End.



Custom Text: By default a linear dimension shows the distance between the two dimension points as text. The text can be replaced entirely, or additional text can be added in front and behind the distance. In the Custom Text field, the <> symbolizes the distance. If you delete these two characters and type in new text, it will be displayed instead. If you leave the <> characters and add additional text, it will be shown with the distance. For example, entering "This wall is <> long" will display "This wall is 10'-0 long" on the screen, assuming the two dimension points are 10 feet apart. If you type, "This is a wall", the dimension will show only that text.


Editing dimensions is discussed further in the Picking and Editing Dimensions section.