These options determine
the transparency of materials. (For example, glass is more transparent.)
Hardware rendered materials with colored transparency and a strong
diffuse color can exhibit dramatically different color results when
semi-transparent. To work around this, use either 100% transparency
or grayscale diffuse colors in hardware rendering. Ray Tracing will
render colored semi-transparency correctly.
Transparency parameters
TipTo view the parameters for
a particular material, select an object with that material and press Ctrl+M.
- Use Color
-
Click the color swatch
to change the color. For details on how to use the Color window
to choose a color, see
Change colors.
Use the slider to adjust the transparency setting. Move it to the
right for more transparency and move it to the left for more opaqueness.
- Use alpha from ‘Color’ image file for transparency
-
If you have used an image
map in the Color parameters and if that image has an alpha channel,
click this button to use that alpha channel to control the surface transparency.
Using the alpha from
the color image file helps you keep the color and transparency maps
aligned. As you move the color map, the transparency map will stay
aligned with the color map pattern.
- Use image file
-
Use a unique image as
a transparency map.
Transparency maps determine
which parts of an object are opaque and which parts are transparent.
They can be used for materials with holes punched out such as a metal
grill or perforated rubber. Darker areas of the transparency map
produce an opaque material, while brighter areas create a more transparent
appearance.
- Invert transparency texture
-
Reverses the transparency
of a defined image file. What was fully transparent will then be
fully opaque, and so on. Identical to opening the transparency image
file in an image editor and inverting the colors.
- Block transparency highlights
-
Block highlights and
reflections for all areas that are 100% transparent. Useful for
simulating holes in solid surfaces.
For details on how to
use these controls, see
Apply image maps.
Ray Tracing Properties
Material transparency
properties that are unique to the Ray Tracing display and rendering mode.
These settings will have no effect on the material when viewed in
Hardware rendering mode.
- Refractive Index:
the physical property determining how much refraction (visual distortion
in transparency due to bending light) is present when transparent.
A value of 1 will result in no refractive distortion at all.
NoteFor accuracy, use
real-world values (such as 1.56 for glass, and 2.2 for diamonds)
whenever possible. Refractive indices are common to all materials,
and lists of real-world values can be found on the internet very
easily.
- Use absorbance:
toggles absorbance coloring and transparency attenuation. Absorbance
is the visual effect of light being absorbed as it passes through
a material, which is a physically accurate version of a transparency
color. The greater the depth of the material, the more light is
absorbed, so transparency becomes less.
- Absorbance color:
the color of the material transparency when the absorbance depth is
reached or exceeded.
- Omit transparency color:
toggles the use of the main transparency color for both color and
transparency amount. Uses only absorbance to calculate the color
and amount of transparency for the object.
- Absorbance depth:
the thickness at which the Absorbance color is achieved for overall
transparency. At depths less than this amount, the transparency
approaches 100% transparent in a gradient.
- Simulate thickness:
Used to add depth-based effects such as refraction and absorption
to transparent objects that are created as a single, infinitely
thin surface.
Simulate Thickness will
"shift" the rays passing through the object to show refraction and
absorption as if there was a second, identical surface at the specified
depth behind the actual transparent surface. However, the ray tracing
effects will not be as accurate with simulated thickness as they
would be with true thickness. This simulation looks best when adding
very small amounts of thickness to single surfaces, such as windows.
NoteNote: Artifacts can
appear in Ray Tracing when simulate thickness is used and the surface
actually has true, modeled thickness, or the amount of simulated thickness
extends "into" a nearby object or the ground plane. In these cases,
it is better to use an accurate model with the thickness built into
it.