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SIMPLE WATER SURFACE

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					SIMPLE WATER SURFACE

One of the few things that make 3D graphics look fake, is that one of the goals of the designer is to make
it look as real as possible. When he uses 3D rendering programs, he tries to recreate an environment that
most people already has first-hand experience with. Organic shapes and objects often look unrealistic,
and that is where the software has been catching up the latest years.

For creating humans and the like, you have metaballs. Plants and trees can be created with fractal
programs, and atmospheric effects, such as rain or fog, has been implemented in most 3D packages. But
the one thing that is causing trouble is how to create water. Most solutions imply using ray tracing and
ripple/wave effects. But 3D Studio doesn't have RT, so you'll have to find another way.

Ok..one of the obstacles is how MAX creates reflections. Basically, it renders various images that are
mapped onto the object, thus creating reflection. This is both good and bad. Good, because it is faster
than RT, and bad because it isn't that accurate. You have two different kinds of reflection; flat and non-
flat. The flat is for mirrors and the like, while non-flat is for rounded objects, such as spheres. So, for a
water-surface, which do I use? The flat reflection looks good if you're just out to have a nice calm pond.
But once you want ripples and waves, you'll need something else. The non-flat reflection (called
Reflect/Refract in MAX) can do this to a certain degree. A non-flat reflection on a flat surface will look
bad; it will be terribly blurred and won't show much. So you'll need either a space-warp to create ripples or
waves, or you'll need a bump map. Here is a quick walk-through on how to create simple water surface
with the standard maps in the 3D Studio MAX materials editor, without using ripplse/wave effects. This is
a way of doing it with a material. Bear in mind that this is not an accurate way of creating water, and will
probably not look good in all scenes. After experimenting with it, it seems that you'll have the bet result
when using it in a scene consisting of a landscape, such as a pond.

Step 1. The first thing you need to do is to create the environmet you want the water in. This can for
instance be a pond or a river. The best way to do this is to create a landscape using the Displace
modifier (this is not the same as displacement map in the Space Warp menu). In this landscape,
wherever you've decided tha water to be, create a box. This box serves as the water surface, so you'll
have to position it so that the top of it is the surface. Here is a simple landscape with the water surface
positioned:
The gray area is the water surface; a simple box with only 1 step in each direction. I merged two
screenshots (one shaded and one wireframe) so you can easily see the box used as a surface.

Step 2 a) Now, the next thing you need to create is the material. Note that this method of creating water
only deals with a water-material, not a mesh. First of all, adjust the Ambient, Diffuse and Specular so
that the water obtains the shine and colour you want. For my water, I use Ambient (0,0,0), Diffuse
(57,57,57) and Specular (255,255,255). Of course, you can tweak this any way you want, giving you the
ability to change the waters main features. A higher value in the Diffuse and Specular will give a whiter
water.




Step 2 b) Now, onto the maps. Click on the map-bar at the bottom of the materials editor so that the
maps rollup. In our case, we need to look primarily at the Reflection and Bump. Click on the empty box
next to the Bump checkbox, and select a new map. Add a noise map here. In this box, you'll need to
experiment with the size and tiling, giving you the kind of ripple you want.
This is the Noise map window. Adjust the tiling and the size of the bump map. You can here see the
values I used for my water.

Again. it's important for you to experiment to get the ripple you're looking for. Remember that the bump
map is your waves. Try it out with different values, and remember to turn of any reflection since you can
see the ripples fine without the reflection (remember to turn them on when you do the final rendering!).
The bump strength should be from 20 to 40. I used 20. Also, during this experimentation, try to pick the
camera angle you want.

Step 2 c) Ok, the next map to add is the reflection map. On the maps rollup, click on the empty box next
to the Reflection checkbox. Add a new Reflect/Refract map and then edit the values for it.
The map size should be set between 500 and 1000. The difference isn't all that big, so you may want to
keep them low. But the you should try to keep them on at least 500. Also, the strength of the reflection
map shouldn't be 100, since the water will look too shiny and clear. 70 is a good value, but again, try to
find a value you want.

Step 4. Now you have the material for the water. Since this method of creating water is stricktly material-
based, all you need to do is apply it to the box you created for surface. In my scene I added no light
sources, so the only light you see is the MAX default light. No shadows are generated. Position the
camera in the angle you want, render and voilá. You have a water surface.

A few tips:

1. Don't rely on this material to reflect any detailed objects. This is a surface that creates a general
reflection of the landscape.

2. Do not have a to high strength on the bump map. The surface will look coarse, and loose details.

3. Atmospheric effects (such as Combustion, Fog, Volume light...) will not be reflected.

4.The larger the map size in the Reflect/Refract is, the longer time is spent on rendering.

Hope this will get you going. Remember that this is a general way of creating water, and that there are
other ways. You can of course use Space Warps to create rippled or waved mesh instead of doing this
through materials. In any case, experiment and see if it fits in your scene.

				
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posted:9/16/2012
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