Printable Version of Topic
Click here to view this topic in its original format
Zoo Admin Forums > General Instructions and Tech Support > Flag Making

Posted by: chek Aug. 20 2004, 09:47 PM
i just downloaded a really good set of flags of some countries from the downlaods section. i'd like to try making some of my own but i'm not really good at doing such things. im wondering if someone can help me out by posting a tutorial on how to make flags? thanks a bunch. =P

Posted by: Aussie Koala Aug. 21 2004, 12:50 AM
There is a tutorial in our tutorial section on making objects. You just need to make your object animated if thats what you mean you want tutorial on.

As this not a building questions I move

Posted by: chek Aug. 21 2004, 02:13 AM
oops. so sorry i left my question in the wrong place. could someone help me out with a tutorial on making animations?

Posted by: Nepenthe Aug. 21 2004, 09:39 AM
Got your message, chek, and I'll continue the conversation in this thread.

Glad you like my flags. Keep watching for updates. The collection isn't finished yet.

There are two issues here -- how to make an animated object in general, and how my flags have the look they do (3-D perspective and shading). I don't have a problem explaining how to make flags in my style -- actually, I'm flattered -- but first comes the part about making objects in general.

I agree with AK. The first step is the tutorials in the tutorial section. This is not a brush-off. People there have already written much better directions than I could. That is where I learned (and less than a year ago). Read the tutorials. Read any discussion threads that might be related to problems you are having.

Any version of APE will be fine for making flags. The flags don't have any of the advanced properties that require an advanced version of APE.

Install Makhor. It can be tedious getting all the system files set up properly, but it is absolutely worth it.

Have you tried anything yet? What have you gotten so far?

What image program are you using? The perspective and shading are easier if you have access to layers and perspective (skew) functions. But you use what you have.

Posted by: chek Aug. 22 2004, 12:33 AM
hi. i followed your advice and installed Makhor. i'm using adobe photoshop 7. i hate to sound like a complete idot but i'm not even sure how to start. i've got images of flags i want. how do i then proceed to do stuff like making the animations and actually putting the pic of the flag on?

Posted by: Nepenthe Aug. 30 2004, 06:47 PM
OK. Sorry this is taking so long. I had a lot of life in the past week ....

Have you been reading the tutorials on making objects? That will get you a lot of the basic mechanincs you are going to need.

As I mentioned before, perspective and shading are going to be the issues in making flags. This is the technique I have been using. If you have had any technical drawing classes, this will be really straighforward. If not, don't panic.
(I suspect GMAX is going to make all this trivial, but I haven't gotten far enough in the tutorials to work GMAX yet.)

Flag-Specific Lesson 1: Getting the Image onto the Flag

The perspective of the flag image has to be right in each frame. If the perspective is in fact right in each frame, then when they are put together the animation looks realistic. If the perspective is not right, the flag image looks like it is not really attached to the fabric of the flag.

Did you ever learn, in art or shop class, how to transfer an image using a grid? Each square in the original corresponds to a square in the second image. And it is much easier to accurately copy one square at a time.

Posted by: Nepenthe Aug. 30 2004, 07:09 PM
Now you try it.

Don't worry for now where the blank flag with the grid came from. That's a different lesson.

Divide your flag image into 16ths -- quarters horizontally and quarters vertically. Copy each square onto the blank flag. Photoshop has a perspective transform, doesn't it? Use the perspective transform to skew your square to fit the square on the blank flag. (I find that, for the most part, I don't need to worry about the curves in the flag at this stage. Trapazoids work surprisingly well.)

The blank flag is approximately 45 pixels high and 60 long. You can start with a larger original if you like. If you start with a smaller original, you may be cheating yourself out of detail

Don't worry about losing detail in the foreshortened parts of the flag. Each animation frame is foreshortened in different places, so the eye is not aware of the loss of detail.

Actually, since the top and bottom of the flag remain parallel, you can successfully copy and transform a whole vertical column at once. That is, you can transfer your flag in four parts (far left, center left, center right, far right), instead of 16.

Once you have your flag image in place, you won't need the grid lines any more. So you can go ahead and cover them up with your image.

Draw in by hand any minor corrections your flag image needs at this point: places where lines don't quite line up, sharp corners that should be smooth curves, etc.

Here is a sample blank flag. It is jpg format because that is what I can post. But you will want to convert it to bmp.

Is this making sense so far?

Posted by: chek Aug. 30 2004, 10:00 PM
wow thank you so much for that detailed tutorial. =) don't worry about taking a long time to post. i'm going to be rather inactive myeslf too (in the midst of my examinations!) tridislike.gif so i'll get down to flag making once its all over. =) thanks so much again for the effort and help.

Posted by: Nepenthe Sep. 6 2004, 12:25 PM
The sample blank flag has a dark background. But APE doesn't care what color the background is, as long as it is a solid color. If your flag image is dark, change the background to any convenient bright, contrasting color. (Use "Select by Color" to select the background, and then "Fill" to replace it with the new color.)

When you have time to get back to this tutorial, post a picture of how your sample flag is coming. Then I will know I haven't lost you. (Or, if I have, I can try to help.)

Lesson 2: Shading

Next step is to put in the shadows.
Perspective makes the image technically correct. Shadows make it look classy.

Using layers in your image software program makes this step simple and elegant.
(Layers have another advantage. Once you have a set of blank flag images and their shadow images saved, it is really easy to make more and more flags.)

First, notice which direction the light is coming from. Look at the flagpole and flagpole base on the blank flag image posted previously. The light is coming from the right side.

Flag fabric is thin enough that if one side is lit up, the other side is too. So flag surfaces that are edge-on to the light (and facing you) will be in shadow, and surfaces facing the light (and turned sideways to you) will be in light.

If you were doing a metal-shiney object, the "light" parts would be brighter than "normal", but fortunately flags don't have that issue. We only have to make the "shadow" parts dark.

Take your flag with its perspective image, from Step 1. Turn on "Show Layers", and make a new, blank layer on that picture. Set the "Blend Options" for this new layer to "Darken". (Some programs have "Multiply" or "Burn". These will all have the same effect as long as you are using gray.)

Select a likely brush style, and a medium gray color. On the new layer , color in gray the parts of the flag that are in shadow. Use a fuzzy brush or airbrush as the flag curves from shadow to light. Very carefully erase any shadow that is sticking out past the edge of the flag. (Easier with a light colored background.)

If the gray is totally covering up your flag image, either you are working on the flag layer instead of the new layer, or the new layer is not set to "Darken."

You should have a nicely shadowed image now.

Save a copy of the shadow layer, as bmp. (Hide all the other layers, and then save. If it was me, I would name it Shadow_SE_0.)

Now unhide your flag image, and merge the layers, giving the final shadowed flag.

Posted by: Nepenthe Sep. 6 2004, 12:42 PM
APE will treat anything that is not exactly the background color as part of your flag, so make sure now that everything is either exactly background color, or really part of the flag. Use "Select By Color" on the background again, on the most sensitive setting. If you find any pixels that are not exactly the background color, use a fine brush to clean them up.

The picture here is a detail of the previous image. Notice the unevenness of the background. This is what you don't want, and need to clean up now. (JPG format spontaneously generates this kind of unevenness, which is why you don't want to be working in JPG.)

Now that you have your image cleaned up, save it, as BMP, under an appropriate name. (I would call this one Smiley_flag_SE_0).

Posted by: Nepenthe Sep. 17 2004, 01:57 PM
Hope the exams are going well. triread.gif Also hope when you get back to this tutorial you aren't too lost.

Moving on to what I think was probably your original question --

Lesson 3: Animations

If you look at real flags, you will notice that their movements are fairly complex. So, unless this is your thesis project in Mechanics, you will want to simplify the motions. You want something easy enough to draw, and recognizably "flaglike." If you compare various flags different people have made, you will see some of the different approaches. I will show you what I do, and once you have the general idea, you can make your own as fancy as you want.

My flag motions are fairly simple compared to some others I have seen. I have four frames of animation in each of the four directions, and the motion is limited to the flag rippling out from the flagpole toward the edge of the flag.

First, draw a perspective rectangle representing the flag in its "unmoving" position. (In ZT, objects in the distance aren't normally drawn smaller than objects up close. I drew the near edge of my flags about 10% larger than the far edge. Do whichever you prefer.)

If you want your flags to line up straight with the ZT gridlines: The gridlines are at 2 pixels horizontal for each pixel vertical.

Divide the flag into a convenient number of equally spaced segments. You will need at least 4 vertical segements, which we will be using later in this lesson. I have drawn one horizontal division also, to show how to do horizontal lines. Horizontal lines are mainly useful as alignment guides for coloring in horizonal stripes on the finished flag.

Posted by: Nepenthe Sep. 17 2004, 02:07 PM
Now expand that flag grid rectangle into a 3-dimensional box, representing the furthest that any part of the flag can move to. This only needs to be a few pixels wide.

(We know the flag always stays attached to the flagpole, so the flag won't really be using the width of the box at the flagpole end.)

(If you think it would be more realistic to make the box narrower at the flagpole end, and wider at the other end -- more of a wedge than a box -- you can certainly do that.)

Make sure you have all the gridlines marked on the sides of the new box.

Posted by: Nepenthe Sep. 17 2004, 02:27 PM
Now the "artistic" part --

The box is marking off all the places where the flag could be. The right edge of the flag will always be somewhere on the right edge of the box. The next-to-right line will always be somewhere on the set of next-to-right lines, etc. You need to pick a set of flag positions that suggest the flag's motion, as constrained by that box. The human eye is amazingly good at filling in between the frames.

A few general hints:
Over the cycle of the animation (in this case, 4 frames), each part of the flag should occupy each edge of the box at least once. (The eye will fill in between frames, but it won't add motion beyond the range it has seen.)

Each part of the flag should not move too much from one frame to the next -- no more than half the width of the box. This gives a smooth motion.

So here is one possible position for a flag motion. (Left edge at flagpole. Next line at far back, next at center, next at far front, right edge at center.)

Posted by: Nepenthe Sep. 17 2004, 04:53 PM
If that is one possible position, here is a set of 4 positions that follows logically from that first one.
(First position pink, second position red, third orange, fourth yellow.)
I am trying here to have ripples moving from left to right.

Notice that I have not yet decided exactly where to place the next-to-left line in frames 2 and 4.

I'm not saying this is the absolute best set of positions. Just that it is one possible set. This step takes some playing around to find a set of positions you really like.

Posted by: Nepenthe Sep. 17 2004, 05:06 PM
Assuming we like this set of positions, let's go back to those pink dots for position 1 and finish that frame of the flag.

It would be convenient to be drawing this flag on a new layer. Then you can use the box of grid lines and a guide, and it will still be easy to copy the clean finished blank flag image. If you don't have the use of layers, you will have more erasing to do at the end.

If you have a function to draw a smooth line through several points, use it now. Otherwise, connect the points freehand with a smooth curve.

Posted by: Nepenthe Sep. 17 2004, 05:07 PM
Do the same thing at each horizontal level.

Posted by: Nepenthe Sep. 17 2004, 05:12 PM
Tthe flag remains straight from top to bottom. We aren't putting in any top-to-bottom ripples. So we can connect all the levels with straight vertical lines.

Erase the grid box (or hide that layer), and you have a blank flag frame, just like we started with in Lesson 1! I promised we would get back to that, and here it is.

Posted by: Nepenthe Sep. 17 2004, 05:17 PM
Do the same thing for each of the four frames. Here I have started frame 2 -- the red dots.

I drew a plausible line from the flagpole to the dots I had already decided on. But what do we do about that next-to-left line? I didn't have a specific dot for it, and we need the line in the finished blank flag.

Posted by: Nepenthe Sep. 17 2004, 05:25 PM
(Nepenthe @ Sep 17 2004, 06:27 PM)
The box is marking off all the places where the flag could be.  The right edge of the flag will always be somewhere on the right edge of the box.  The next-to-right line will always be somewhere on the set of next-to-right lines, etc.

So that means the missing line has to be somewhere in the blue rectangle.

We know where the top of the flag intersects the blue rectangle, we know where the bottom of the flag intersects the blue rectangle, and we know those two points will be connected with a straight vertical line.

Posted by: Nepenthe Sep. 17 2004, 05:27 PM
So that wasn't really much of a problem after all.

Posted by: Nepenthe Sep. 17 2004, 05:30 PM
Oops, I forgot the middle horizontal line. (That wasn't a tutorial gimick. I really did forget it.)

But we know how to put it in.

And the second frame of the flag is finished.

Posted by: Nepenthe Sep. 17 2004, 05:50 PM
I use four frames in each of the four directions, for a total of 16 frames I need for each flag.

(Four directions, viewing the flag from four sides, right? Northeast, Northwest, Southeast, and Southwest


The animations for NW are going to be mirror images of NE, and SW are mirror images of SE. So you will need to generate 8 frames from scratch (4 each for NE and SE), and then copy and reverse them for NW and SW.
The animations are mirror images. The flagpole isn't, because the light is coming from the right. So you can't flip the whole image. You have to cut out the picture of the flag, flip it, and paste it back onto the other side of the flagpole.

You can certainly make more frames, if you want more realistic motions. The Blue Fang US Flag uses 11 frames for each direction.

Some people say you need at least 4 frames on a moving object to keep APE from crashing. (APE is not the most robust program. Just be glad it works at all. Mostly.) I've never tried less than 4. And I think you probably need at least 4 frames to get a reasonable flag motion, anyway.

And finally, I'm including the flag blank set I am currently using. I hope you read all the tutorial anyway, because you wouldn't really know what to do with these without the rest of the tutorial.

Good luck, and will we be seeing more new flags in the downloads soon?

Powered by Invision Power Board (
© Invision Power Services (