Draw a first-aid kit with Inkscape

Draw a first-aid kit with Inkscape

The tutorial provides example of using 3D box tool in Inkscape to create a base for a complex object in perspective and explains drawing complex shadows.

In the previous tutorial I explained basics of creating 3D looking objects in Inkscape using a snowman as an example. However one tutorial cannot possibly fit all the tricks I would like to share with you. Besides, some tools that are very much 3D related weren't even mentioned back then.

So this time let's draw a computer's first-aid kit [1].

Final image of the first-aid kit

The very first thing to do is creating a base for the image. It doesn't really sound any complicated, because it's basically a simple box. But you just try to do it by sketching and you'll see that unless you have a very good sense of perspective, the box will look clumsily. Then you are likely to recall that Inkscape has guides (you drag them from rulers), so you can use them to create lines that define vanishing points. All right, you use them and create three visible planes and fill them with color... only to discover that you now want to change your point of view slightly. Would you want starting everything from scratch again? There is a better way.

Inkscape has a specialized tool to draw 3D boxes. It's very handy for creating bases for buildings, all sorts of boxes, furniture and so on. The great thing about it is that you can drag around the created 3D box in 2.5D to pick the point of view that suits the project best. And you can also change size and color of sides.

Drawing a 3D box

By default one of the vanishing points is set to infinity. This is useful when you need to picture an object in one plane, say, a horizontal plane. But we are placing the first-aid kit angled towards horizon. In that very case the box should have three vanishing points. So let's disable parallelism of edges, position the object the way we need it, define final size and change colors.

Changing vanishing points

In Inkscape a 3D box is basically a well hidden (from user) group of six paths plus some extra metadata. Now that we have the box our way, ungroup the 3D box (Shift+Ctrl+G, or "Object > Ungroup") and remove the "invisible" sides (i.e. the ones that are obscured when you look at a box in 3D). Easiest way to do it is click elsewhere to remove selection from automatically selected sides, go to Outline view mode (View > Display mode > Outline) and use Alt+Click to select the sides that you don't see, then press Del for each one.

Now duplicate the visible sides (Ctrl+D, or "Edit > Duplicate") and apply union boolean operation (Ctrl++, or "Path > Union"). The resulted path is a blank for the main outline of the future kit, which still has to be rounded. Let's first create guides from this object (Shift+G, "Object > Objects to Guides") that will cross each other exactly in vanishing points which is where we are going to need them.

Creating guides from the object

And we are going to need them right now as constraints for rounded edges of the box.

The edges are positioned between flat sides, so we can use linear gradients to imitate rounding. As a matter of fact there should be angle gradients with centers located in the vanishing points. But since angles between rounding borders are relatively small, and the lightness of sides doesn't differ much, the cone shape of these roundings can be safely ignored, and would not have to mess around with imitation of an angled gradient.

There is another simplification to benefit from. We'll apply gradients only to the edges we see in front of us. The ones that are further from us can be painted with blurred shadows. That way it will also be easier to show rounding of box's vertices on same visible outline. And the vertex that is closest to us will be worked on in details later.

So let's go back to the guides that constrain edge roundings.

When guides are created from an object, their rotation centers (small blue circles, see previous screenshot) are automatically placed where nodes of a broken line had been. Axes should be shifted (press and hold Ctrl for that) to vanishing points. Only then you should rotate guides (press and hold Shift, then drag). I recommend doing all that with snapping enabled (%, or "View > Snap") to simplify aiming at points where guides cross.

Creating a rounded corner using a gradient

Let me remind you that the best way to create arbitrary shapes like the rounding areas here is using Pen tool to draw Bezier paths.

It's best to edit gradients right on the canvas and pick colors for color stops right from the box's sides. In that case the gradual transition will really look smooth as it should be. And of course direction of gradients should be perpendicular to the respective edges.

Let's finish all three edges, filling the vertex where they meet as well. Right now that vertex looks like it's broken, but it's just how things are at this stage.

Creating another rounded corner using a gradient

Let's figure out what exactly is the vertex here. Basically it's a point where three planes converge. But this "point" has a radius. And since colors of the planes gradually change, and there is some radius of transition, let's try a radial gradient here.

Draw a triangle on top of the angle with vertices laying on tops of the flat sides. Place the center of the radial gradient in the top vertex of the triangle which is the lightest one. The opposite color stop has to have color of the darkest part of the first-aid kit. Now you need to take care of the third side. Move the gradient's center towards it, but return the focus back to the lighter side (press and hold Shift, then drag a small cross for that). The result is more or less fine, but the top path's borders will still be seen. You can fix that by turning triangle's sides into slight slopes and adding more color stops to the gradient.

Finishing the front upper corner

When you round top path of the box, you have to keep in mind that the visible corner rounding radius is equal to the actually defined one only as long as all three adjacent edges are seen. For corners with two visible edges rounding radius may vary from real one to zero depending on the angle of the plane with edges. I haven't managed to find methodology of calculating such radii yet, which is why I relied on intuition and, um, used a lid of some bottle in the bathroom as a sample :)

Rounding rear corners

And now let's use the outer path to create an outline shadow that will imitate rounding of the rest of the edges. For that duplicate the path, place some arbitrary larger path underneath it and subtract (Ctrl+-, or "Path > Difference").

Apply a gradient and blur to the resulted path.

Applying a gradient to the top

Duplicate the outer path of the kit again, group everything except it and use the duplicated path as a clipping path for the newly created group ("Object > Clip > Set").

Clipping path applied

Okay, the box shape is ready now.

Use guides to draw a red cross and a fissure between two halves of the box. Round the path of the fissure on corners the same way you did it for the outer paths of the kit. Then place a highlight on top of it.

The highlight and the red cross should be filled with a slightly noticeable linear gradient. While polishing the illustration I also applied gradients to the kit's sides.

Adding highlight shape

Not it's time for the wire. You can draw it with a Pen tool using a very thick stroke and then outlining that stroke (Ctrl+Alt+C, or "Path > Stroke to Path). Duplicate the wire twice. Make the first copy lighter and shift it a little towards top. Make the first copy darker and shift it a little towards bottom, then blur both copies. Duplicate the original path again and apply it as clipping path.

Add shadows beneath the wire and the kit's box. Use several differently blurred objects to create a complex compound shadow.

Addng a bottom shadow

Here is what it looks like in wireframe mode:

Everything in wireframe mode

The path of the sharper part of the wire's shadow becomes narrower towards the kit's box. Along with blur it creates effect of decreasing sharpness.

Use the same principle for the box's shadow. The shape of its sharpest and darkest part repeats the path of the boxes's bottom side. It is visible just because it's very slightly blurred. The lighter and more blurred parts jut out much further.

Now you can add a shadow and a slight reflection from the wire to the side of the box, then a reflection from the plane on which the box is placed. Adjust shadows and highlights on the wire close to the place where it enters the box.

Adding shadow from wire on the box

Finally, draw the thin colored wires hanging out, add some shadows and colored reflections for them.

Coloured wires

And we are done!

The final first-aid kit image

[1] The phenomenon is widely spread in ex-USSR countries where people actually pay to tech support that is not affiliated with vendors they got their computers from. The service is usually called something like "PC ambulance". Hence the first-aid kit metaphor.

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54 Responses. Comments closed for this entry.

  1. Darn, I get to the point where it says “remove the invisible sides”...
    (in paragraph, just below the 3rd illustration)
    and then can’t get any further.
    What ? Remove the sides of the cube ? the invisible sides ?
    if they are invisible, how can I remove them (silly)
    Can anyone clarify this for me ?

  2. Heya, as the text states, the 3D box is basically a group of four shapes. When you ungroup, all of them are selected. Click somewhere else to deselect them, go to Outline view mode (View > Display mode > Outline) and use Alt+Click to select the sides that you don’t see, then press Del for each one. I’ll probably enhance the text now :)

  3. Thanks for the clarification.
    OK, I get it now, the 3D tool is only used to create the initial basic shape in a proper perspective. Beyond this we just proceed using nodes & vectors to refine the details ?
    Now I can proceed, and thanks for the cool tut.

  4. Beyond this we just proceed using nodes & vectors to refine the details ?

    Exactly :)

    Now I can proceed, and thanks for the cool tut.

    Welcome :) More are coming.

  5. Yuriy is an Inkscape magician :D
    Thanks a lot to him for making a tutorial and to you for translating it.

    It’s great, now I know that those annoying little dots on guides are actually rotation centers, hehe.

    Aces should be shifted (...)

    Access, maybe ?

  6. After Objects to Guides, how do you go to the guides in the next step?

  7. Interesting - sometimes when I do Object to Guides, the resulting guides duplicate when I drag them, and I can get the guide picture shown in the article.  Not sure about moving the center - no rotation seems necessary because the duplicated guides are parallel.

    Can’t figure out why sometimes it works and sometimes it doesn - seems to have something to do with whether I delete the invisible sides or not…

  8. Interesting - sometimes when I do Object to Guides, the resulting guides duplicate when I drag them

    This is quite unusual. Presumably you are using 0.47. On what system? Could you please try to reproduce it with 0.48 prerelease?

  9. Ah, here comes a question from su-v: did you do Union operation on visible sides?

  10. Yuriy_Apostol 21 July 2010 at 12:35 pm

    Aces should be shifted (...)

    Access, maybe ?

    It’s a misprint. In russian instead of “rotation centres” I used the term “rotation axes”.

  11. It’s a misprint. In russian instead of “rotation centres” I used the term “rotation axes”.

    Fixed ;)

  12. How do you make a second guide that’s parallel to the first?  That seems to be the key to setting up the guides to make the edges…

  13. @gbell12: which step are you referring to?

  14. this is a horrible tutorial, nothing is in detail, i have no idea how to do any of this stuff.

  15. Dear sageofrage, knowing basics of using Inkscape is a prerequisite. Otherwise this would be a book, not a tutorial :) Perhaps the tutorials should state that explicitely.

  16. Hi prokoudine - sorry for the delay - am still checking back here!

    The photo right before the text that says “Let me remind you that the best way to create arbitrary shapes like the rounding areas here is using Pen tool to draw Bezier paths.”  That photo has a bunch of guides that are parallel to the original edges.  They’re key for drawing the gradients because they define the start and end.  But I don’t see how to duplicate a guide so that it’s parallel to the first…

  17. Jose Luis Triana 01 May 2011 at 12:19 am

    I just got to this step “Let’s finish all three edges, filling the vertex where they meet as well.” but, where that edges “meet as well”? It has to do with the intersection of the guidelines? or how I may define that points?

  18. I’m rather puzzled by some operations. In particular, it seems it is not possible to do an Alt-Click pick with my system (Debian+Gnome 2.x) because this combo is used by the DM to move windows around the desktop. From the pictures, it seems the tutorial has been made on some Linux flavor anyway.

    I’ve ended up in fiddling with the regular pick and see how the result looks like (hint: horrible).

    Thanks for the great tutorial anyway.

  19. @ntropia Yes, the tutorial is done on Ubuntu and GNOME with reconfigured key for moving windows

  20. In my opinion this tutorial doesn’t explain well how to draw radial gradient for round corners. I tried the same teardrop shape but it didn’t work as well, perhaps because I had more extreme color differences on box sides. I had to improvise and use lots of shapes and blur to get the same look for that tricky corner.


  21. Alexandre Prokoudine 18 November 2011 at 8:45 pm

    I wish we could upload the original SVG file for everyone to inspect it, but unlike the snowman tutorial this picture is a commercial work.

  22. @Alexandre

    how about partial area that shows the construction of the corner? Or a picture that describes in more detail how the author adds more radial gradient stops.

  23. Can this be done in Adobe Photoshop?

  24. Everything is possible :)

  25. since when do first aid kits have electrical wire coming out of them?

  26. Since the beginning of 2011, didn’t you read the news?

  27. Alexandre Prokoudine 30 December 2011 at 12:23 am

    @ridesh The last paragraph in the tutorial is there for a reason ;-)

  28. I am not familiar with Inkscape. I usually use Corel Draw and Cad to make 2D and 3D image. Anyway this tutorial can help me to have other method to draw 3D Box.

  29. Wow, this is very good work and thank you for doing this! I hope you will create more of these tutorials.

  30. Hi & first of all thanks for this fine tut (also for the snowman lesson). For the first time I used “Object-to-Guides” which is a great help. But I have the same question as a prior user: how do I create parallel guides for the “red cross”? I’m lost here. :-/

  31. Alexandre Prokoudine 31 January 2012 at 12:35 pm

    Ronny, you can double-click a guide to copy its angle to the clipboard, then create a new one and paste the value. We do need better UI for guides :)

  32. Thank you, Alexandre. :)


  34. Alexandre Prokoudine 14 February 2012 at 1:58 pm

    @Surfer21 Oh, sorry for the wait.. Could you please quote the exact paragraph that’s causing the problem?

  35. This is a great tutorial, you are very talented, it looks great

  36. If you post a tutorial for others, use simple, grammatical language. I couldn’t understand whole sections.

    “When you round top path of the box, you have to keep in mind that the visible corner rounding radius is equal to the actually defined one only as long as all three adjacent edges are seen.”

    I have to read this 5 times just to parse it. And then I have a dozen questions: Why would the adjacent edges not be seen? What top path? Visible corner rounding radius?! Sounds like a tongue twister. Is there an “of” missing there somewhere.

    At some point, I just stopped trying to read this and got through at least some of it by following the screenshots alone.

  37. Alexandre Prokoudine 23 April 2012 at 3:43 am

    Vlad, first of all, I think your complaint is valid. I’m not a native English speaker, and translating this tutorial was particularly difficult, so there definitely is a lot of room for improvement. I think a partial rewrite would help, but it’s going to take some time, while new stuff keeps coming. TL;DR: we’ll improve it, but not immediately. Thanks!

  38. in this tutorial I am stuck on the where you have to round the edges of the box its not explained very well btw thanks for putting in the effort for actually making the tutorial

  39. Very, very beautiful! Nice job and thank you for the tutorial.

  40. Hi,

    This is unquestionably a very talented artist! The work is very inspiring…

    I have done many tutorials for various 2D and 3D applications in my day. I have found that this is a great way to LEARN a new application (not just learn a technique on a program one already is familiar with).

    Regrettably, I am simply unable to follow this tutorial for lack of detail, as I am still LEARNING Inkscape.

    It would be fantastic if this talented artist could collaborate with an equally talented teacher, and would compile the tutorials in a more accessible form to individuals who are not only wanting to learn graphic techniques but also to learn this tool. Perhaps a slow-paced video version of these tutorials would help to eliminate the ambiguity in the text…?

    Nevertheless, I appreciate the effort and the spirit of sharing knowledge.

  41. Great!!Extremly admire the author’s skill!!!

  42. oohh.. So that is how to do it. I was trying to design it but I have a problem with the dimension also. Thank you for posting this one.

  43. This tutorial illustrates an amazing piece of work. However, for noobs like myself, I frankly couldn’t make much sense of it and I got stuck at step one. Would it be possible to see more explanation added on the use of the tools? Great tut! Nick

  44. Alexandre Prokoudine 26 January 2013 at 9:38 am

    @Nick, the tutorial was targeted at users already somewhat familiar with Inkscape. How exactly verbose do you want it to be to become useful for you?

  45. @Alexandre Prokoudine the tutorial is explained in pretty easy language and I am new to Inkscape but I got all the points in the tutorial :)

  46. Great work done on this tutorial. Presentation is up to the mark with useful information. Thanks for the great tutorial anyway.

  47. This is awesome, at first I think this is 3d.
    Great tutorial, I’m trying this software and I’m still confuse to use it, lol.

  48. Useful tutorial , this was really in depth , great work guys .

  49. Awesome tut! How do you add the groove to the middle of the box? (Do you simply draw it there witht he pen tool, or is there a better way to do it?)

  50. it looks great to effort for actually making the tutorial

  51. I loved it, A great tutorial of inkscape, it looks like 3d look.


    PLS update the tutorial ....and make itwork properly..

  53. Alexandre Prokoudine 18 November 2015 at 12:34 pm

    @viki, fixed, thanks for telling!