Practical Autodesk AutoCAD 2021 and AutoCAD LT 2021
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Rotate with Reference

In the previous case, the door symbol was at an angle of 0 degrees (perfectly horizontal) and hence, its rotation angle can be specified pretty easily. But let’s now take the case of this window symbol. It is inclined to an unknown angle and so, to rotate this to any specific angle, we will use the rotate with reference option:

        Figure 2.57: A window symbol inclined to an unknown angle

Here, the window symbol is inclined to a random angle with respect to the horizontal axis. Now, if you want to rotate this window symbol so that it becomes perfectly horizontal, then you need to use the Reference subcommand of the Rotate command.

To do this, I will once again start with the Rotate command:

  1. Type RO and press Enter to start the Rotate command or click its icon in the Modify panel of the Home tab.
  2. Select all the objects that make the window and press Enter.
  3. Click on the A point to specify the base point.
  4. Select the Reference option from the command line, or type R and press Enter to select the Reference option.
  5. Now, you need to specify the reference angle and in this case, we will specify it by clicking on A and then the B point.
  6. Now, the command line will prompt you to specify the angle. Type 0 and press Enter.

You will notice that the window will now become horizontal; that is, its angle will now be 0 degrees, as in the following diagram:

  Figure 2.58: The window symbol after rotating it with respect to the reference

In this case, by specifying the reference angle, you can make AutoCAD rotate the drawing to any specific angle with respect to the positive side of the axis, even when the angle to which the object is inclined is unknown.

The next modify command that we will discuss is Fillet and this command lets you add rounded corners. It may look like a tool that can make subtle changes to the drawing, but you will find it pretty useful as it not only makes rounded edges, but it also has other sets of useful features, which we will discuss in the next section.