Underwater Scene

Tutorial: Underwater Scene By Jarek Dukat Let's start creating our underwater scene. The first thing is the bottom. The easiest way of creating it is nurbs surface with noise modifier or displacement map, but it is not the matter of this tutorial. First thing to do when you have the bottom is setting up the main light. Good choice here is directional light with large radius. Use white color for this light. As you know light refracts on water surface. Unfortunately, MAX (and other programs) can't simulate this effect even using raytracing. So we have to fake this effect using projector map for the light. MAX 2 has procedural Water texture and we will use it. MAX 1 users can play with noise texture and achieve similar effect. Sample settings for the water projector map are below:

Depending on scale of your scene you will have to adjust Wave Len Max and Min settings. When the map is ready you can just drag&drop it from material editor to Projector map button in light's properties. When you have the projector applied your test render should be similar to the one below (the bottom on that picture has only white diffuse color, no texture, and the blue waves are caused by light and projector):

The blue background color you set up in Rendering/Environment. Use color with RGB values about 0, 96, 102. Use darker color for deeper water effect. Water is not 100% transparent, even very clear water. Objects that are far are less visible than those close to the camera. The best way of simulating this effect is using Fog. You can add fog in Environment menu. Below you can see settings for the fog:

Most important settings are Fog color (use blue similar to background color) and Near% and Far% values. These two parameters define how dense your fog is in near range and far range of your camera. This is a good moment to set these values for camera too. When camera is close to water surface you often can see light beams in water. You can simulate this effect in MAX using volumetric lights. First you have to add new light to your scene, with much smaller radius than the main light. Here also we will use projector map but this time it won't be water waves. We need black and white irregular dots - such projector map will produce many light beams from single spot light. Below you can see (condensed) settings of noise texture that will be used for this projector:

Depending on your scene's scale you will have to adjust noise Size. RGB Level increased to 4 produce more contrast, brighter spots. Now apply this map as projector. When the light is ready go to Environment again and add Volume Light effect. Use setting similar to these below:

With all projectors, fog and volume lights your test rendering should look like this one:

To add a little more realism to your scene you can make some bubbles or alga floating in the water using simple particle system. Snow emitter is enough for this, use very slow particle speed (important if you want to animate your scene) and facing particles. Suitable Particle Size you have to find yourself. Material for particles: Standard, white (or bright blue), 100% self illumination, and circular gradient for opacity map. This will produce fast and nice effect of bubbles in the water. Underwater scene makes no sense when there are no object in the water. With only one light from top your objects will be too dark, so you can add some fill light from one or two sides. You can exclude the bottom from this light if it is too bright. Also, if you want your main top light to cast shadows, they may be too dark (almost black) - shadows in water are never completely black. Solution is very easy: just clone your main top light and decrease multiplier to 1/2 for both lights. Now turn Cast Shadows on for only one light. Remember that for lights with large radius you will probably have to increase Shadow Map Size and Sample Range. Your scene is ready :)

Sample MAX 2 scene ~44 KB Downloaded from www.The3dStudio.com