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1504 Chapter 16: Material Editor, Materials, and Maps
can assign vertex colors using the Ve r t e x Pa i nt
Modifier (page 1–918)
,the Assign Vertex Colors
utility (page 2–1544)
,orthevertexcontrolsforan
editable mesh (page 1–992) , editable patch (page
1–959)
,or editable poly (page 1–1026) .
While vertex color assignment is primarily used
for special applications, such as game engines or
radiosity renderers, y ou can also use it to create
colorful, gradient surface effects. You can also
useitindesignvisualization:Usethe
Ve r t e x P a i nt
Modifier (page 1–918)
to paint your landscape
different colors to represent grass, shrubbery,
parking areas, etc., and then use Vertex Color
map to use the vertex coloring in y our rendered
images. Incidentally, when you use the
Te r r a i n
object’s (page 1–342)
Color By Elevation function,
the software assigns a material that uses a Vertex
Color map as the diffuse component.
Tip: To view vertex colors in a viewport, right-click
the object, choose Properties from the quad menu,
and then turn on Vertex Channel Display in the
Display Properties group.
Procedure
To use the vertex color map:
1.
Assign vertex colors to an object.
2. Assign a material to the object, then assign
a Ver tex Color map to the material’s diffuse
component.
3. Optionally, if m anipulating the map channels
w ith the
Channel Info utility (page 2–1549) ,
choose a map channel or sub-channel to render.
4. Render the scene.
Interfa ce
These parameters let you define w hich map
channel or sub-channel is to be rendered. One
application is to support usage of the Vertex Color
map in conjunction with the
Channel Info utility
(page 2–1549)
.
The settings are interlinked; changing one
parameter w ill change the other two, as
appropriate.
Map Channel—Lets you specif y w hich map channel
to use. Range=0 to 99. Default=0.
Notes regarding this setting:
• If you set Map Channel to a channel that doesn’t
contain any vertex coloring data, attempting to
render will generate a Missing Map Coordinates
error message. To resolve this, apply vertex
coloring to that channel.
• By default, the vertex coloring in map channel
1 is a color gradient derived from the UVW
texture coordinates by converting UVW values
to RGB values. Thus, at UV=0,0 (the lower-left
corner of the map), the coloring is black; at
UV=1,0, the coloring is red, and at UV=1,1
(the upper-right corner), the coloring is yellow
(red + green=yellow). You can change these
colors with a tool such as
VertexPaint modifier
(page 1–918)
.
• Map Channel cannot be set to a negative value,
thus the map doesn’t suppor t rendering of the
vertex illumination (-1) or vertex alpha (-2)
channel.