Graphics Programs Reference
In-Depth Information
• From step 9 to step 18, we built the main bump effect, this time piped dir-
ectly as a whole in the
Displacement
input of the
Material Output
node
rather than to the per shader
Normal
inputs.
• From step 20 to step 25, we built a supplementary bump effect, this time
to simulate the big waves you can usually see on the desert sand dunes.
This effect is left apart from the main bump to be easily reduced or elimin-
ated if the case, and we added two
Math
nodes set to
Multiply
and driv-
en by a
Value
node to automatically set the size of the sand big waves
(actually, this is more of a "repeating" effect, that is, the bigger the value,
the smaller and closer the waves).
• In steps 28 and 29, we built a last bump effect to add, if necessary, the
sand grain, for example, for objects very close to the camera. From step
31 to step 33, we summed all the bump effects as a whole, to be driven
by the
Math
node value.
Every stage has been "framed" and labeled to make it more easily readable in the
Node Editor
window.
There's more...
One more thing we can do to improve this material is to combine everything in a
"group" node, leaving, at the same time, the fundamental values exposed to be
tweaked from the interface.
1. Put the mouse cursor in the
Node Editor
window and press
B
. Horizontal
and vertical lines now appear at the mouse cursor's location, left-click and
drag the mouse to encompass the framed nodes, leaving outside only
the
Texture Coordinate
, the
Mapping
, and the
Material Output
nodes.
After the mouse button is released, everything you encompassed is now
selected.
2. Press
Crtl
+
G
and confirm by clicking on the
Make Group
|
New
pop-up
and create the group:
