The texture mesh module serves two needs. First, the need for
a robust module for mapping 2D data to quadrilateral meshes
is served. The input 2D data may be a 2D uniform field, in
which case the x,y coordinates for the output mesh is derived
from the extents information (if present) or using a mapping
from indeces to space if no extents information is present. The
z values are obtained from the data in the field.
In 2D rectilinear fields, the x,y coordinates are explicitly
provided. The z values are obtained from the data.
In 2D, 3-space irregular fields, all coordinates are specified.
In 2D, 2-space irregular fields, the mapping is the same as
in rectilinear data.
The second need fulfilled by this module is support for texture
mapping. Two types are supported. The first, called "dynamic"
in AVS parlance, is the traditional type of texture mapping where
the coloring of the surface is postponed until rendering time.
The second type, called "explicit" here will color the vertices
of the field based upon the image on the second input port, along
with the uv coordinate ranges specified by the user.
Control over the uv coordinates is explicitly supported for this
module so that the user may move the texture around, or scale the
texture using the parameters provided. Non-affine transformations
along with rotations (of textures on the surface) are not
supported.
This module uses in-line field texture calls available from
AVS 5.01.
Note: This module at present does not work on Dec Alpha OSF.