“Wet Floor” signs

This is an entry in DESIGNS DISASTERS. Everywhere I go I see bad design, not so much in terms of taste, but in technical execution. If you aren’t hiring a professional designer the costs to you are lost time, shoddy work, and possible embarrassment.

This is a bad wet floor sign:



This is what’s wrong with it:floor2

See how the width of the the black outline grows larger around the corners? It looks so sad and blobby.

You know right away that the designer doesn’t care about uniformity and nice clean lines. But the real problem is that this is a telltale sign of a designer who does not understand how Illustrator interacts with shapes: how to draw shapes, how to scale shapes, and how to align shapes. These shape functions are the backbone of what Illustrator is made to do. What does that infer about the competency of designer who doesn’t understand the basic functions of their tools?


This triangle is sloppy:

In Illustrator we draw regular polygons (other than squares) using the polygon tool. By default the corners are always pointed. To round the corners you apply a “round corners effect” which will ask for a radius measurement in so many units, let’s say we input 10px. Now we need to draw the yellow triangle that is inside the black one. The incorrect, lazy method you see here is to copy the black triangle and shrink it. The problem is this also shrinks the corner radius out of sync with the original black triangle. Now the corner arcs diverge and you get that blobby corner where the black outline is wider in the corners than at the sides.

Another way to draw this shape is to apply a black stroke (outline) to a yellow triangle. I find this “less perfect” for a couple of technical reasons. One is that depending on your scaling settings you will have a black outline that is too thick or thin, or a corner radius that appears tiny or gigantic. The setting can be changed, but that is disorienting to your workflow and will create ridiculous stroke and radius values like 52.972. If you had to apply this shape with a mathematical level of precision it becomes very difficult to work with. For example, Illustrator will tell you the size of an object’s path, but that does not include the stroke, which could be some random number. Consequently when you request a triangle of size “x” and your designer sets it to that size and then applies a stroke it will be anything but what was requested. If the triangle is near text, other objects, or has to fit in a physical space you have problems. There are always workarounds to make the stroke method work if you want, but it is clumsy.


This is how the align tool will centre equilateral triangles:

Screen Shot 2016-08-13 at 14.21.25


Some people will draw two triangles and then use the align tool to centre the inside one, then fill with the background colour so it knocks out the centre of the larger triangle. This doesn’t work either.

Illustrator doesn’t centre equilateral triangles on their centroid (the point at the intersection of lines drawn from the centre of all bases to the opposite corner), or their circumcenter (the point at the centre of a circle touching all bases at a tangent, which is the same point on an equilateral triangle).* Instead it draws an imaginary rectangle around the triangle touching all corners and outputs the centre of said rectangle. Dumb? Kinda! But consequently the “centre point” is dragged too high and you get the alignment seen above.


This is an example of a correctly executed triangle:

If you were to measure the width of this black outline it will be the same at any point (no droopy corners). This is because the corner radius was scaled in proportion to the overall shape of the triangle. The correct (read: most accurate and most efficient) method is to use the “offset path” function, expanded shapes, and you are good to go: you can scale the shape to any size, for any application, set the size with certainty, and all of your ratios will stay in place. I guarantee it will always look the same at any size anywhere.

This method is also the best because it correctly centres the triangles on each other, unlike the other methods.

The beauty of computers is their ability to take human error out of mechanical tasks like aligning things with perfection. But if the user undermines this ability, all the benefits of computers are gone. Since offset path grows form the centroid it will be perfect every time.

Questions or comments? How do you draw shapes? Do you disagree with how I do things? Let me know!

*In the newest version there is a tool to make this easier, but not better. Knowing how to drive a car doesn’t make you a mechanic, but being a mechanic could inform your driving.

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