The passed array should not be overwritten or freed while the
texture is active because the array may be needed to reload texture
memory if the texture memory is invalidated by the need to load
other textures.
The user may also pass a null array, and later fill all or part of
the texture memory allocated for the texture with the subtexload or
fbsubtexload commands.
TTTTXXXX____MMMMIIIINNNNFFFFIIIILLLLTTTTEEEERRRR specifies the sample-filtering function used to
generate the texture function output when multiple image pixels
correspond to one pixel on the screen. This token is followed by a
single symbol that specifies which minification filter to use. For
many Graphics Library implementations, texturing performance is
constrained by the number of samples used by the filter per texture
function output. The classical 2D MIPmap filter needs to access
eight image pixels for each screen pixel. Performance and quality
may be traded by limiting the number of samples used, and the
computations necessary to find the samples.
TTTTXXXX____PPPPOOOOIIIINNNNTTTT selects the value of the image pixel nearest to the _s,_t,_r
mapping onto the texture. (2d or 3d)
TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR selects the weighted average of the values of the four
image pixels nearest to the _s,_t mapping onto the texture. (2d
only)
TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____LLLLEEEEQQQQUUUUAAAALLLL ((((oooorrrr TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____GGGGEEEEQQQQUUUUAAAALLLL)))) selects the four image
pixels nearest to the _s,_t mapping onto the texture. The value of
the _r texture coordinate is compared with each image pixel. If _r
is less than (or greater than) the image pixel, the result is
maximum image pixel value. Otherwise it is 0. The four
comparison results are bilinear blended. This feature is useful
for real-time shadow computations. (2d only)
TTTTXXXX____TTTTRRRRIIIILLLLIIIINNNNEEEEAAAARRRR selects the weighted average of the values of the
eight image pixels nearest to the _s,_t,_r mapping onto the texture.
(3d only)
TTTTXXXX____BBBBIIIICCCCUUUUBBBBIIIICCCC uses a smooth weighting of a 4x4 region of image pixels
nearest to the _s,_t mapping onto the texture. (2d only)
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____PPPPOOOOIIIINNNNTTTT chooses a prefiltered version of the image, based
on the number of image pixels that correspond to one screen pixel,
then selects the value of the pixel that is nearest to the _s,_t,_r
mapping onto that image. (2d or 3d)
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____LLLLIIIINNNNEEEEAAAARRRR chooses the two prefiltered versions of the image
that have the nearest image pixel to screen pixel size
correspondence, then selects the weighted average of the values of
the pixel in each of these images that is nearest the _s,_t,_r
mapping onto that image. (2d or 3d)
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR chooses a prefiltered version of the image,
based on the number of image pixels that correspond to one screen
pixel, then selects the weighted average of the values of the four
pixels nearest to the _s,_t mapping onto that image. (2d only)
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____TTTTRRRRIIIILLLLIIIINNNNEEEEAAAARRRR chooses the two prefiltered versions of the
image that have the nearest image pixel to screen pixel size
correspondence, then selects the weighted average of the values of
the four pixels in each of these images that is nearest the _s,_t
mapping onto that image. The weighted averages from the two levels
are then themselves interpolated. (2d only)
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____QQQQUUUUAAAADDDDLLLLIIIINNNNEEEEAAAARRRR chooses the two prefiltered versions of the
image that have the nearest image pixel to screen pixel size
correspondence, then selects the weighted average of the values of
the eight pixels in each of these images that is nearest the _s,_t,_r
mapping onto that image. The weighted averages from the two levels
are then themselves interpolated. (3d only)
The default minification filter is TX_MIPMAP_LINEAR or a filter of
equal performance, but better quality. Prefiltered versions of the
image, when required by the minification filter, are computed
automatically by the Graphics Library. The TX_MIPMAP_FILTER_KERNEL
token, described below, specifies the 8x8 (2D) or 8x8x8 (3D) filter
kernel used by the Graphics Library to generate MIPmap levels.
TTTTXXXX____MMMMAAAAGGGGFFFFIIIILLLLTTTTEEEERRRR or TTTTXXXX____MMMMAAAAGGGGFFFFIIIILLLLTTTTEEEERRRR____AAAALLLLPPPPHHHHAAAA or TTTTXXXX____MMMMAAAAGGGGFFFFIIIILLLLTTTTEEEERRRR____CCCCOOOOLLLLOOOORRRR specifies
the filter function used to generate the texture function output
when multiple screen pixels correspond to one image pixel. It is
followed by a single symbol that specifies which magnification
filter to use. The sample-filtering function can be specified
seperately for alpha and non-alpha texture function outputs with
TX_MAGFILTER_ALPHA and TX_MAGFILTER_COLOR. One possible use of this
seperation of alpha and color magnification filters is for the case
where non-zero alpha defines a geometry-approximating template such
as a tree outline. The following token sequence TX_MAGFILTER_ALPHA,
TX_SHARPEN, TX_MAGFILTER_COLOR, TX_BILINEAR can be used to keep the
outline of the tree sharp without any color-shift side effects of
the sharpening magnification filter. The magnification filter
symbols are:
TTTTXXXX____PPPPOOOOIIIINNNNTTTT selects the value of the image pixel nearest to the _s,_t,_r
mapping onto the texture. (2d or 3d)
TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR selects the weighted average of the values of the four
image pixels nearest to the _s,_t mapping onto the texture. (2d
only)
TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____LLLLEEEEQQQQUUUUAAAALLLL ((((oooorrrr TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____GGGGEEEEQQQQUUUUAAAALLLL)))) must be used in
conjunction with the same TTTTXXXX____MMMMIIIINNNNFFFFIIIILLLLTTTTEEEERRRR. (see TTTTXXXX____MMMMIIIINNNNFFFFIIIILLLLTTTTEEEERRRR above)
TTTTXXXX____TTTTRRRRIIIILLLLIIIINNNNEEEEAAAARRRR selects the weighted average of the values of the
eight image pixels nearest to the _s,_t,_r mapping onto the texture.
(3d only)
TTTTXXXX____BBBBIIIICCCCUUUUBBBBIIIICCCC computes a smooth weighted average of a 4x4 region of
image pixels nearest to the _s,_t mapping onto the texture. (2d
only)
TTTTXXXX____SSSSHHHHAAAARRRRPPPPEEEENNNN attempts to magnify the image without blurring. It may
only be used with mipmapped textures. It computes the weighted
average of the values of the four pixels that are nearest the _s,_t
mapping onto that image for each of the top two levels of a
tttteeeexxxxddddeeeeffff2222dddd is immediate mode only. IRIS-4D G, GT, and GTX models, and the
Personal Iris, do not support texture mapping. tttteeeexxxxddddeeeeffff2222dddd is ignored by
these machines. tttteeeexxxxddddeeeeffff3333dddd only accepts images of size 2^j x 2^k x 2^l
where j,k,l are non-negative integers. Non-power of two images are not
accepted. This is different than texdef2d, but consistent with OpenGL.
The Iris Indy, Indigo Entry, and XL support texture mapping except for
lines. Use ggggeeeettttggggddddeeeesssscccc to determine whether texture mapping is supported.
TTTTXXXX____MMMMIIIIPPPPMMMMAAAAPPPP____TTTTRRRRIIIILLLLIIIINNNNEEEEAAAARRRR is not supported on the VGX model.
It is acceptable to define a 4-component texture function on an IRIS-4D
VGX, or VGXT, system that does not have alpha bitplanes. However, this
definition will be treated as a 3-component definition by tttteeeevvvvddddeeeeffff. Use
ggggeeeettttggggddddeeeesssscccc((((GGGGDDDD____BBBBIIIITTTTSSSS____NNNNOOOORRRRMMMM____AAAALLLLPPPPHHHHAAAA)))) to determine whether alpha bitplanes are
available.
Points, lines, and characters, as well as polygons, are texture mapped.
Filter selection and wrap modes are applicable to lines. Points are
filtered by the magnification filter, assuming a 1-to-1 correspondence
between texture pixel and screen pixel size. Characters use the same
magnification filter, but are mapped assuming that both _s and _t are zero.
IRIS screen pixels have integer coordinates at their centers. Texture
images, however, have integer coordinates (0 and 1) at their exact edges,
not at the centers of pixels on their edges.
On IRIS-4D VGXT models tiling large images will improve texture quality
only when the individual tiles measure no more than 1/4 the original
image size in either dimension.
On IRIS-4D RealityEngine models the only MIPmap filter used is
TX_MIPMAP_TRILINEAR for 2D and TX_MIPMAP_QUADLINEAR for 3d. All the other
forms of MIPmap filters will default to these filters.
The IRIS-4D G, GT, GTX, VGX, VGXT models, Personal Iris, Iris Indigo, and
Indy do not support tttteeeexxxxddddeeeeffff3333dddd, TX_BICUBIC, TX_MAGFILTER_COLOR,
On IRIS-4D VGX, and VGXT when using TTTTXXXX____TTTTIIIILLLLEEEE, _w_i_d_t_h and _h_e_i_g_h_t of both the
original image and the specified subregion must be a power of 2.
On IRIS-4D VGX model when using TTTTXXXX____TTTTIIIILLLLEEEE, texture coordinate _t is always
clamped to the range 0.0 through 1.0 regardless of the value of
TTTTXXXX____WWWWRRRRAAAAPPPP____TTTT.
On IRIS-4D VGX model when TTTTXXXX____WWWWRRRRAAAAPPPP____SSSS is set to TTTTXXXX____CCCCLLLLAAAAMMMMPPPP, TTTTXXXX____WWWWRRRRAAAAPPPP____TTTT also be
set to TTTTXXXX____CCCCLLLLAAAAMMMMPPPP. Otherwise operation is undefined.
On IRIS-4D VGXT models when using TTTTXXXX____TTTTIIIILLLLEEEE, and TTTTXXXX____WWWWRRRRAAAAPPPP____TTTT, TTTTXXXX____WWWWRRRRAAAAPPPP____SSSS, or
TTTTXXXX____WWWWRRRRAAAAPPPP are set to TTTTXXXX____CCCCLLLLAAAAMMMMPPPP, the texture coordinates in the corresponding
dimension must be within the closed range [0,1].
On IRIS-4D RealityEngine models TTTTXXXX____TTTTIIIILLLLEEEE and TTTTXXXX____SSSSEEEELLLLEEEECCCCTTTT do not work
together.
In the Graphics Library Programmer's Guide (1992) pg. 18-30 eq. 18-1
should read:
M,N = 256/(2^(2+N))
and the TX_DETAIL example that follows should read:
TX_DETAIL,4.,4.,16.,16.,0,
On Infinite Reality and Impact TTTTXXXX____TTTTIIIILLLLEEEE , TTTTXXXX____SSSSEEEELLLLEEEECCCCTTTT , TTTTXXXX____DDDDEEEETTTTAAAAIIIILLLL, and
TTTTXXXX____SSSSHHHHAAAARRRRPPPPEEEENNNN are not supported. They do not support TTTTXXXX____MMMMAAAAGGGGFFFFIIIILLLLTTTTEEEERRRR____CCCCOOOOLLLLOOOORRRR or
TTTTXXXX____MMMMAAAAGGGGFFFFIIIILLLLTTTTEEEERRRR____AAAALLLLPPPPHHHHAAAA. They do not support TTTTXXXX____FFFFAAAASSSSTTTT____DDDDEEEEFFFFIIIINNNNEEEE with TTTTXXXX____PPPPIIIIXXXXMMMMOOOODDDDEEEE
TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____LLLLEEEEQQQQUUUUAAAALLLL, TTTTXXXX____BBBBIIIILLLLIIIINNNNEEEEAAAARRRR____GGGGEEEEQQQQUUUUAAAALLLL, and they do not support
