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1542 Chapter 16: Material Editor, Materials, and Maps
Usethetoggletoenableordisableuseofthe
map(default=on).Usethespinnertoincreaseor
decrease the map’s effect .
Channel Direction group
By default, the Normals map’s red channel
indicates left versus right, whi le green indicates up
versus dow n (and blue indicates vertical distance).
The controls in this group let you adjust that
interpretation.
Flip Red (X)—Flips the red channel so that left and
right are reversed.
Flip Green ( Y)—Flips the green channel so that up
and down are reversed.
Swap R ed & Green—Swaps the red and green
channels so that normal mapping rotates 90
degrees.
Method group
The Method group lets you choose w hich
coordinate to use on the normals. These controls
arethesameasthoseinthe
Projection Options
dialog (page 3–160)
.
•
Tangent—(The default.) Project at a tangent to
the target object’s surface.
This is t he method to use for objects that both
move and deform, such as animated charac ters.
•
Local X YZ—Project using the object’s local
coordinates.
This met hod can be used for stationar y or
moving objects, but not for objects that deform:
if the object deforms, the projection will appear
incorrectatsomeframes.
•
Screen—Project using screen coordinates; that
is, flat projection in the Z axis. X is horizontal,
increasing in a positive direction to the rig ht;
Y is vertical, in creas ing in a positive direction
upward; and Z is perpendicular to the screen,
increasing in a positive direction toward the
viewer.
This method is useful mainly for stationary
objects seen only from a single angle; for
example, a statue seen through a window.
•
Worl d —Project using world coordinates.
This is u seful mainly for objects that don’ t move
or deform; otherwise, a moving object with
world-projected normals will appear to “swim”
through the texture.
Camera Per-Pixel Projection
Cam era Map Per Pixel
Material Editor > Maps rollout > Click a Map button. >
Material/Map Browser > Camera Map per Pixel
The Camera Map Per Pixel lets you project a map
from the direction of a particular camera. It is
meant as an aid to 2D matte painting: you c an
render a scene, adjust the rendering using an
image-editing application, then use this adjusted
imageasamattethatisprojectedbackontothe
3D geometry.
Here is a more detailed workflow for using Camera
Map Per Pixel:
1. Create the 3D model.
2. Set up a camera.
3. Set up the rendering resolution you want.
To get good results, t he plate should b e at least
2K pixels; 3K to 6K, or higher, is recommended.
4. Render the scene to an editable image format
such as
TIFF (page 3–684) .
5. Render the scene again, this time to a format
such as
RPF (page 3–681) that has a Z-depth