Graphics Programs Reference
In-Depth Information
Figure 18.14
Figure 18.15
Rendered image
18.3.6 Example 4
This example demonstrates the use of material nodes in
combination with other objects in the scene. The objec-
tive here is to create a simple graduated material. First,
we have to set up the scene as shown in Figure 18.16; the
default cube has been elongated into a vertical column,
and a simple plane object has been added to the scene,
scaled up, and positioned behind the elongated cube,
forming a backdrop in the camera view (Figure 18.17).
Make sure the lamp is positioned on the camera side of
the plane. Select the plane in the 3D window and as-
sign the default material and a marble texture to it in
the properties window - “Material” button. Deselect
the plane then select the elongated cube. In the proper-
ties window - “Material” button - “Diffuse” tab, pick a
diffuse color, and in the “Specular” tab, pick a specular
color. In the “Transparency” tab, tick “Transparency” and change the “Alpha” value to 0.000.
While still in the “Transparency” tab, click “Raytrace” and set the “IOR” value to 1.2. In
the properties window - “Render” button - “Shading” tab, untick “Shadows.” The diffuse
and specular colors can be anything you want. Obviously, “Transparency” makes the cube
transparent; with the “Alpha” value at 0.000, it is fully transparent. The “IOR” value is an
angular index of refraction for ray traced refraction; the value of 1.200 makes the cube
appear to look something like glass. Only by experimenting with different values will you
understand how to achieve the outcome you want.
