AutoCAD Dynamic Input: Love it or Hate it?

A question that I get asked a lot, is how do you turn Dynamic Input in AutoCAD off? In this post I will discuss not only how to turn Dynamic Input off and on, but also how it works, what is different, and a few of the options available when using it.

If you would prefer this content in video form, please check out these videos I made on this topic:

First, I will admit it, I am not a fan. In fact, in the textbook I wrote, A Practical Guide to AutoCAD, I have students disable it in the first exercise. That way their interface will match the rest of the book, which does not use Dynamic Input (shocking!). I do however demonstrate it and give the students a chance to try it, and encourage them to use it if they are more comfortable working that way.

When Autodesk added Dynamic Input to AutoCAD many releases ago, I was initially excited. I always try to get my students to get used to looking at the Command line so that they can learn all of the options that are available to them when drawing. I often have students change the color of Command line so that it is more eye-catching. The idea of Dynamic Input is that you do not need to look at the Command line. Instead, everything (in theory) will be easily accessible right next to your crosshairs.

What is Different?

Dynamic Input affects the way coordinates are entered. By default in AutoCAD, all coordinates entered are absolute, meaning that they are relative to the origin (0,0). To draw with relative coordinates (in relation to the last point placed) you type the @ symbol in front of the coordinate.

For example, a line is started at the absolute coordinate of 2,2. Entering 5,3 for the next endpoint would draw to the absolute coordinate of 5,3. Entering @5,3 would draw 5 units to the right, and 3 up relative to the previous point. You can see the difference below:

Autodesk AutoCAD Dynamic Input - Comparison of absolute and relative coordinates.

What does this have to do with Dynamic Input? By default, coordinate values are relative when using Dynamic Input. In fact, you can look at the Command line and you will see that AutoCAD literally enters the @ sign for you. So what can you do if you really want to enter an absolute coordinate? You have to type the # symbol before the coordinate. After using AutoCAD the “normal” way for so long, I just can’t change my mindset on that. Typically I try to embrace the new ways to do things not just in AutoCAD, but in other CAD applications I use. I just can’t (or won’t) do it in this case.

Let’s talk about angles. By default, angles in AutoCAD are positive in the counter-clockwise direction:

Angles in AutoCAD

You can draw in the clockwise direction by entering a negative angle. For example, to draw the line below using polar coordinates, I could type @2<315, or I could type @2<-45.

Angles in AutoCAD

Dynamic input simplifies this (kind of). You do not need to worry about positive or negative as the angle is based upon the location of the crosshairs. If you bring the crosshairs above horizontal, it will draw the line 45 degrees up. If you bring the crosshairs below horizontal, it will draw the line 45 degrees down.

Angles in AutoCAD

This is probably great for new users. For experienced users who are used to working with positive and negative angles, this could be confusing. If the crosshairs is below horizontal, and you type -45 for your angle, it is going to draw up in the (traditionally) positive direction. This can be extremely confusing.

The last difference I want to discuss is the ability to see command options. Whether Dynamic Input is on or not, you can see the options for the current command in the Command line. You can even click on the option there, or type in the capitalized letter. You can also press the down arrow key on the keyboard to open up the dynamic menu:

AutoCAD Dynamic Input Options

I am not a fan of this workflow as it adds a keystroke every time I want to use an option.

Turning Dynamic Input Off

Several releases ago Autodesk decided to not only turn Dynamic Input on by default, but they also hid the button to disable it. To show the button, click the three lines on the far right-side of the status bar (sometimes referred to as the “hamburger”). In the menu, select Dynamic Input. It is important to note that this does not turn Dynamic Input on or off, it merely displays the button on the status bar. Of course, you can than use the button to turn it off.

Turn AutoCAD Dynamic Input Off

Alternatively, you can type DYNMODE at the Command line, then set it to 0.

Turn AutoCAD Dynamic Input Off - DYNMODE = 0

As I tell my students, I don’t expect people to do things the way I do them. It is important for everyone to be comfortable with their workflow, as that is what is going to make them most efficient.

What do you think? Am I just an old timer stuck in my ways? Do you use Dynamic Input? Let me know what you think in the comments!

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