| clamp none -or- s -or- t -or- st
Determines the meaning of texture coordinates outside the range 0..1.
With clamp none , the default, coordinates are interpreted
modulo 1, so (s,t) = (1.25,0), (.25,0), and (-.75,0) all refer to
the same point in texture space. With s or t or
st , either or both of s- or t-coordinates less than 0 or
greater than 1 are clamped to 1 or 0, respectively.
file filename
alphafile filename
Specifies image file(s) containing the texture.
The file file's image specifies color or lightness information;
the alphafile if present, specifies a transparency ("alpha") mask;
where the mask is zero, pixels are simply not drawn.
Several image file formats are available; the file type must be
indicated by the last few characters of the file name:
.ppm or .ppm.Z or .ppm.gz 24-bit 3-color image in PPM format
.pgm or .pgm.Z or .pgm.gz 8-bit grayscale image in PGM format
.sgi or .sgi.Z or .sgi.gz 8-bit, 24-bit, or 32-bit SGI image
.tiff 8-bit or 24-bit TIFF image
.gif GIF image
(Though 4-channel TIFF images are possible, and could
represent both color and transparency information in one image,
that's not supported in geomview at present.)
For this feature to work, some programs must be available in
geomview's search path:
zcat for .Z files
gzip for .gz files
tifftopnm for .tiff files
giftoppm for .gif files
If an alphafile image is supplied, it must be the same size
as the file image.
apply modulate -or- blend -or- decal
Indicates how the texture image is applied to the surface.
Here the "surface color" means the color that surface would have
in the absence of texture mapping.
With modulate , the default, the texture color (or lightness,
if textured by a gray-scale image) is multiplied by the surface color.
With blend , texture blends between the background color
and the surface color. The file parameter must specify a
gray-scale image. Where the texture image is 0, the surface color is
unaffected; where it's 1, the surface is painted in the color given
by background ; and color is interpolated for intermediate values.
With decal , the file parameter must specify a
3-color image. If an alphafile parameter is present,
its value interpolates between the surface color (where alpha=0)
and the texture color (where alpha=1). Lighting does not affect the
texture color in decal mode; effectively the texture is
constant-shaded.
background R G B A
Specifies a 4-component color, with R, G, B, and A floating-point
numbers normally in the range 0..1, used when apply blend
is selected.
transform transformation-matrix
Expects a list of 16 numbers, or one of the other ways of representing
a transformation (: handlename or < filename ).
The 4x4 transformation matrix is applied to texture coordinates,
in the sense of a 4-component row vector (s,t,0,1) multiplied on
the left of the matrix, to produce new coordinates (s',t')
which actually index the texture.
|