onno van braam
computer graphics, webdevelopment

Tutorials

Composite Maps


This tutorial will describe how to use composite maps in 3D Studio Max. Composite maps are a different way of putting decals/logo's on your object, other than having to unwrap it and make large bitmaps in PhotoShop.

First step is to create the object on which we'll put the composite map, and for simplicity I made a single plane of 200 by 200 units (square).

With the plane selected, go to the Material Editor and in the diffuse slot add a new map: a Composite Map.

When you have done that, you see something like the next image: you can set the number of maps by clicking the 'Set Number' button, but for the time being we'll just use two maps, because we want to put two logo's (the Pirelli and the Brembo logo) on the plane.

To do this we need two different maps for each logo: one for the color and one mask. The mask image will 'blend' the base material color with the diffuse color of your color image. It'll become clear in a sec, if you don't exactly understand what I am saying.

Blend/Mask and Diffuse map for the Pirelli Logo.

Blend and diffuse map for the Brembo Logo.

Combined diffuse and blend maps: I made the maps perfectly square so that they're easier to work with later on. When we'll apply UVW Map modifiers to our object, I don't want to think about what measurements/dimensions/relative x / y size it should have, so I make it square and that way it's easy to set the x and y size of the UVW Map since they're the same, they have a ratio of 1:1.

Map 1: Pirelli Logo.

So on with Map 1 of the Composite Material. Click the 'None' of Map 1, it'll bring up a pop-up with different type of maps and select Mask.

The Mask Map has again two slots: one Map (we'll use the Pirelli color bitmap for this) and one Mask map. The Mask map blends (as said) between the base color and the Map.

Click the Map slot, select Bitmap from the list, and select the Pirelli diffuse/color map wherever you have stored it. Note that in the screenshot it's still the small logo, not the square one, I changed them only afterwards and forgot to remake a screenshot...

Uncheck the U and V tiling radio buttons: we only want to put a single logo on our plane, not a repeating pattern.

After you did all that, click the 'Go to Parent' button to go up one level in your material.

Repeat the previous process for the Mask map, only now select the mask bitmap, in stead of the Color bitmap.

So the Composite Map now has a Mask Map in Map 1, and the Map map (pardon the jargon here, but they decided to call the diffuse color map in the Mask map 'Map') has the color bitmap in it, and the Mask has the blend/mask bitmap in it.

Next up is to repeat the previous steps for Brembo logo which will go into Map 2 of the Composite map.

The only difference is to change the Map Channel to 2 for both the diffuse and the blend bitmap. Change the name of the Mask maps to something like 'Brembo Logo' and 'Pirelli Logo' so that you can find them easily.

That pretty much wraps up the work in the Material Editor! The nasty part is over, now comes the fun part: playing with the logo's on your object.

Adding UVW Maps

Add two UVW Map modifiers (Planar ones), rename them to match the material names ('Brembo Logo', 'Pirelli Logo'), by right clicking them in the list in the Modify panel. Change the Map Channel of the Brembo UVW Map to 2, so as to match Map Channel you set just now in the Material Editor.

Go back once more to the Material Editor and set the Show diffuse Pirelli map in viewport, by going into the Composite Map then the Pirelli Logo Mask and the Map (diffuse) slot and click the 'Show Map in Viewport'...

... and if everything went okay, it should show up in your viewport as below.

And now for the magic: go to sub-object of Pirelli UVW Map, by clicking on it in the Modify panel (so the Pirelli Logo UVW map) so that it becomes yellow to indicate you're in the sub-object. Now you can move your UVW Map around and the beauty is: your logo moves along with it!.

I moved the UVW Map a bit downwards just for examplary purposes.

Go to sub-object of Brembo UVW Map and move it too, only a bit upwards.

This is basically the whole key to Composite Maps: you can move your logo's/decals, all around the object you are mapping, without doing complicated unwrapping, or making large UVW Maps in PhotoShop which kills memory wise when rendering.

So time for a test render! Below you can see it, and there are some notes about what is what. Also not the horizontal lines, which are due to me making sloppy Masks which had some compression in them and therefore weren't perfectly white/black.

Hierarcy/Order of Maps in Composite Maps

Now it's time to dig a little deeper into how Composite Maps work. You could for instance ask yourself what would happen if the two maps were put on top of each other by moving the UVW Maps both the center of the plane. Well, why not do it, but first I changed the diffuse/color Map of the Pirelli Mask Map to a black version so that you can see the difference between the Brembo and Pirelli logo (they were both red).

Left is the original order of the maps in the Composite Map (Pirelli in Map 1, Brembo in Map 2) and on the right is them reversed (Brembo in Map 1, Pirelli in Map 2).

You can swap the materials by dragging one onto the other and selecting 'Swap' as the Copy method and click OK.

So this means: the higher the Map number in the Composite Map list, the more on top it is. So if you would want to make a complicated textured car with lolads of vynils for instance, you would work 'back-to'front': everything what is in the background goes in Map 1, then what is on top of that in Map 2 and what if above that in Map 3 etc. etc.

Scaling of UVW Maps

So far we have only worked with the default size of the UVW Map (i.e. being as large as our object), but what if we want the logo to be smaller than what it is now? You could make it smaller on the bitmap, but that's a lot of work (you have to do the Diffuse and the Mask bitmap) and besides, it's a irreversible process, you're resaving your bitmaps. All in all, that's not the way: you can just scale your UVW Map. Go into the Sub-Object of the Pirelli Logo UVW Map and make it a bit smaller by scaling it, using the 'Select and Non-Uniform Scale'.

This is one of the beauties of Composite Maps: you can move and scale your logo's and decals at will all over your object without having to worry about unwrapping, changes to your mesh, the size of the logo etc.

Adding additional logo's

If you want to add more logo's, you have to add more Maps to the Composite Map, as follows:
- Set number of Composite Maps, 1 higher than it is now.
- Copy old map (of the logo you want to duplicate or if you want to make a new to save some time making the Mask etc.) to the new slot.
- Change map channels of diffuse and blend bitmap.
- Add a new UVW Map to the object and change the UVW Map map channel to the one you just set in the Material Editor.

I think it's good practice to match your Map Channels of your bitmaps and UVW Maps to the Map number of your Composite Map. That way you avoid consfusion and errors.

If one would use Composite maps compared to UVW Unwrapping, there are pros and cons:

pros:
- Fast placement of each decal/logo and you can instantly put it where you want it.
- No huge bitmaps, that take a lot of memory while rendering.
- No UVW Unwrapping, which can be a really big pain in the rear and which you have to redo every time you change your model.

cons
- Your material can become quite extensive (having a lot of Maps) when you have loads of decals, like on a race car.
- Your model would need a lot of UVW Maps when you have a lot of Maps, which in turn is memory intensive.


Comments

boomtown.cowboy
2010/06/14
Tnx a lot, greeting from Belgrade, Serbia
ray
2010/03/31
excelent work! thanks, it helped me a lot
Radix
2009/03/09
Really what I was looking for, nicely explained and easy to follow.
Thanks,
Radix
www.i2arts.com
Mandeologul
2008/08/05
Thank you very much, I thought that is has to be simple, but couldn't find out myself thanks again.
chris.
2007/08/22
nice tutorial, i've been trying to figure this one out myself for quite some time now... thanks!
Ben
2007/06/10
This explains exactly what I've been seraching for how to do. Thanks a ton mate.
Billabong
2007/05/30
Hello Onno, I really appreciate you doing this small tutorial. It has helped out tremendously, but I am having a problem with the edges of my decals shoing up, could you explain a little more on to get them not to show up please. thanks again
Peter
2007/05/17
Hello Onno,
thanks for sharing. Excellent tutorial, the one on composite maps. I kept being confused with Blend masks etc. This tut is very useful. Finally I can move images(like logos) around, and scale them, without goeing backwords and forwards to photoshop. Keep up the good work, it is appreciated.