9.5.2

838 • CHAPTER 18
MATERIAL EDITOR • 839
Color, Delta
Clipping is often attempted with texture images that are antialiased; this produces a bright border
around an object caused by the antialiasing of colors between the main texture and the alpha color;
you can remove this border by adjusting the deviation sliders.
You can use clip mapping (also sometimes called ‘genlocking’) to mask particular areas with a Color
value. Using this method, you pick the color from the selected image that you wish to become
transparent. The downside is that often the areas you wish to become transparent contain several
colors and the resulting alpha can leave a seam around the object. However, by setting the Delta color,
you can dene by how much the color may deviate; this can help to reduce the seam.
Use alpha channels built in to the texture to mask areas softly and more accurately (see ‘Image Alpha’,
below).
Invert
This option simply inverts the alpha, so transparent and solid areas are reversed. This works for both
clipped images and images with built-in alpha channels.
Soft
This enables you to fade textures and materials from one to another, which gives you even more ways
of creating realistic-looking objects. With Soft enabled (the default setting), the Color and Delta
settings lose their meaning. The texture map is now used to decide which ranges should be faded.
A white texture pixel in the image means that here the material is to be 100% opaque. If the texture
pixel is black, the underlying material shines through 100%.
Image Alpha
If you notice black areas when rendering objects that have multiple alpha materials, increase the Ray
Depth value on the Options page of the render settings.
If you apply a material with a CINEMA 4D Alpha channel to an object and the object has no underlying
material, the object will be non-existent at the points where the alpha allows the underlying material
to show through.
With Image Alpha enabled, you can use any existing alpha channel of the loaded image. Alpha
channels of the TIF, TGA, PICT, Photoshop PSD and QuickTime MOV image formats are supported (as
well as all QuickTime supported formats). If no alpha channel is present in the image, the Image Alpha
option will be ignored. Use the Invert function to invert the alpha channel without having to rework
the texture in your image editor.