I am drawing a figure which shows several tetrahedrons in Illustrator. I have drawn all the line segments and connected them at the endpoints. Now the figure has been like this.

Now I want to fill the areas surrounded by the line segments. I did this as follows: first selected 3 line segments, join them and fill the color.

However, I found another problem. Since there are dashed lines in this figure, if the 3 line segments contains one which is dashed, the join operation will cause all the lines dashed. That is what I don't want.

So What is the correct operation if I want to meet my purpose? enter image description here

  • Could you please add the layers panel showing the shapes?
    – Ilan
    Commented Apr 23, 2014 at 14:25
  • There should be only one layer here. Please see the updated figure.
    – C. Wang
    Commented Apr 23, 2014 at 14:40

1 Answer 1


I answer the question as I understand the task, thus probably there can be some inaccuracies in the answer.

If I understand you properly, you want to fill by color all the surfaces enclosed by solid lines.

For this task I would hide all the dashed lines, select All the solid lines and Expand them.

Next, I'd Unite them to create Compound shape.

Finally, I'd fill the surfaces with colors adjusting all the properties of the fills as needed.

At the end, unhiding the dashed lines should give you the desired "3d" look.

NB! If you don't want to play with Opacities - Place all dashed lines above the solid ones in the Layers panel.

Not the answer you're looking for? Browse other questions tagged or ask your own question.