To make an impossible Penrose Triangle in Illustrator following tools are used:
- Rectangle Tool
- Rotate Tool
- Pen Tool
- Shape Builder Tool
Penrose Triangle is famous among artists and designers since 1934 when Swedish artist Oscar Reutersvärd created it for the first time. Penrose Triangle also known as impossible triangle is an optical illusion which is not valid in real life.
Even though Penrose Triangle do not exists in real life we can make it’s 2D illusion form. To create Penrose Triangle vector in Illustrator, step-by-step process is crafted below.
Creating a new Document
Open Illustrator and start with a New Document ‘Penrose Triangle’. Make a square document of width and height 1000 px and select measurement as Pixel. You can also use other measurement options. From advanced options select color mode to RGB.
Picking thickness for Penrose Triangle
Select Rectangle Tool by pressing ‘M’ on keyboard. Then left mouse click on the artboard to get settings for Rectangle Tool. Make square of width and height 100 px.
After making a square of width and height 100 px, fill square with bold color with no stroke. Now, keep pressing alt (or option) key and drag square to bottom. This will create a duplicate of square.
To make sure whether the outline of both squares are vertically intersecting or not, turn on Smart Guide. Smart Guide provides information for aligning images properly into it’s respective place. To turn on Smart Guide go to ‘View’ on top navigation bar and check ‘Smart Guides’ (or press Ctrl + U).
Making guide lines for Penrose Triangle
To get Ruler option go to ‘View’ on top navigation bar, then to ‘Rulers’ and select ‘Show Rulers’ (or press Ctrl + R). On the top and left side of artboard Ruler panel will appear. To use Ruler, drag guide line form the ruler panel. Also, check on ‘Snap to Point’ which will be useful later.
Now drag guide lines from the top Ruler panel on the three horizontal outlines of squares. Here, size of the squares only determines the thickness of the cuboidal triangle. At last select both square with selection tool ‘V’ and delete it with Delete or Backspace key.
Select all three guide lines and go to ‘Object’ -> ‘Transform’ -> ‘Rotate’.
Create a copy by Rotating the above three guide lines at an angle of 60 degree.
Again, select the three horizontal guide lines and go to ‘Object’ on top navigation bar -> ‘Transform’ -> ‘Rotare’.
This time, rotate three horizontal guide lines at an angle of 120 or 240 degree and make a copy.
Make a rectangle of width 180 px and height 100 px and place it between the upper two horizontal guide lines.
Select all guide lines rotated at an angle 60 degree and snap it to the top left part of rectangle. Again, select all guide lines rotated at an angle 120 or 240 degree and snap it to the top right part of rectangle. At last delete the rectangle. As in picture, guide lines will form an equilateral triangle.
Now select all the guide lines and lock them by going to ‘View’ on the top navigation bar -> ‘Guides’ -> ‘Lock Guides’ (or press Alt or Option + Shift +;). To prevent guide lines from moving from it’s place, it is locked.
Making Penrose Triangle with Pen tool
Select or press ‘P’ on Keyboard for Pen tool. Now start making triangle and the other outlines with Pen tool by clicking points at the intersection of guide lines. Follow process as shown in picture above.
After making outlines, unlock guides by pressing (Alt or Option + Shift + ;). Then select all the guide lines and delete.
Adding individual shapes for Penrose Triangle
Only creating outline will not let you add shades or fill because there are no individual shapes till now in Penrose Triangle. So, to make shapes select all the outlines using selection tool and press ‘Shift + M’ on keyboard for Shape Builder Tool. Now, individually make shapes for closed compound by clicking and adding shape with mouse.
As shown in the above picture there are three shapes to make/add with Shape Builder Tool. After adding shapes for individual compound, each compound will form a new shape. At last add shade or fill to the shapes from color palette.
There are also other ways to draw impossible Penrose Triangle in Illustrator. You can learn making it with other tools as well. Making Penrose Triangle drawing entirely on rectangle tool is also easy to try. So, learn making same image with different tool, and it will make you find the easiest and time saving process for your next illustration. Keep practicing!