AutoLISP Tutorial 4: Creating a Custom Layer in AutoCAD

Layers are integral to the organization of designs in AutoCAD. By effectively managing layers, we can significantly improve the clarity and efficiency of our work. This tutorial will guide you in creating a nifty AutoLISP tool that aids in the creation and management of layers in an interactive manner. With user-friendly prompts and feedback, even the most complex tasks can become a breeze.

Tutorial 4: Creating a Custom Layer in AutoCAD


For this exercise, your task is to design an AutoLISP function that facilitates the creation of a new layer in AutoCAD. The function should be user-friendly and interactive.


  1. Initiation: Start by setting up your environment. Ensure that command echoes in the command line are temporarily suppressed to provide a clean interface.
  2. Layer Name Input: Prompt the user to specify a name for the layer they wish to create.
  3. Layer Verification: Before creating the layer, verify if a layer with the same name already exists in the drawing.
  4. Color Selection: If the layer name is unique, ask the user to provide a color for this layer.
  5. Layer Creation: Using the provided information, create the new layer with the specified name and color.
  6. Reattempt: If the provided layer name already exists, inform the user and prompt them to enter a new name. Continue this process until a unique layer name is given.
  7. Termination: Restore any settings or configurations you altered at the beginning, and ensure a clean exit from the function.

End Goal:

By the conclusion of this tutorial, you should have a functioning tool that allows users to effortlessly create new, uniquely-named layers with their preferred color in AutoCAD.

Best of luck, and remember: clarity and user experience are key!

Tutorial 4 Solution: Crafting a Layer Creation Tool

Understanding the nuances of AutoLISP allows us to create powerful tools that can significantly enhance the user experience in AutoCAD. In this tutorial solution, we’ve designed an interactive tool that aids in the creation of a new layer. Let’s break down its components step by step.

The Complete Program:

(defun C:tuto4 ( / stp1 layn coln )
(setq svcm (getvar “cmdecho”))
(setvar “cmdecho” 0)
(setq stp1 1)
(while (= stp1 1)
(setq layn (getstring “\nEnter the name of the layer you want to make: “))
(if (= nil (tblsearch “LAYER” layn))
(setq coln (getstring “\nEnter the color of the layer: “))
(command “-LAYER” “m” layn “c” coln layn “”)
(setq stp1 0)
(princ “\nThat layer name already exists, try again”)
(setvar “cmdecho” svcm)

Line by Line Explanation:

(defun C:tuto4 ( / stp1 layn coln ):
This line initializes a new AutoLISP function named “tuto4”. The variables stp1, layn, and coln are defined as local to this function.

(setq svcm (getvar “cmdecho”)):
This captures the current command echo setting in AutoCAD and stores it in the variable svcm.

(setvar “cmdecho” 0):
Suppresses the command echo, providing a cleaner user interface.

(setq stp1 1):
Initializes the stp1 variable to 1, which is later used as a flag in the while loop.

(while (= stp1 1):
Initiates a loop that will continue as long as stp1 is equal to 1.

(setq layn (getstring “\nEnter the name of the layer you want to make: “)):
Prompts the user to specify a name for their desired layer.

(if (= nil (tblsearch “LAYER” layn)):
Checks if the layer name provided by the user already exists in the drawing.

(setq coln (getstring “\nEnter the color of the layer: “)):
If the layer name is unique, this line prompts the user to specify a color for their new layer.

(command “-LAYER” “m” layn “c” coln layn “”):
This line creates the new layer using the provided name and color.

(setq stp1 0):
Sets the stp1 variable to 0, ending the while loop after a unique layer name has been provided.

(princ “\nThat layer name already exists, try again”):
Notifies the user that their specified layer name is already in use, prompting them to try again.

(setvar “cmdecho” svcm):
Restores the original command echo setting from before the function’s execution.

Cleanly exits the function without returning any unwanted values to the command line.

In Conclusion:

Congratulations on completing this tutorial! You’ve now equipped yourself with a powerful tool that simplifies the layer creation process in AutoCAD. By embracing the capabilities of AutoLISP, you’re not just enhancing your AutoCAD proficiency but also creating a more streamlined and productive design workflow. Always remember, with the right tools and understanding, every challenge becomes an opportunity to excel.