IRIX Base Documentation 2002 November/SGI IRIX Base Documentation 2002 November.iso/usr/share/catman/g_man/cat3/standard/texbind.z/texbind

Text File | 2002-10-03 | 6.1 KB | 133 lines

tttteeeexxxxbbbbiiiinnnndddd((((3333GGGG))))                                                        tttteeeexxxxbbbbiiiinnnndddd((((3333GGGG))))



NNNNAAAAMMMMEEEE
     tttteeeexxxxbbbbiiiinnnndddd -  selects a texture function

CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
     vvvvooooiiiidddd tttteeeexxxxbbbbiiiinnnndddd((((ttttaaaarrrrggggeeeetttt,,,, iiiinnnnddddeeeexxxx))))
     lllloooonnnngggg ttttaaaarrrrggggeeeetttt,,,, iiiinnnnddddeeeexxxx;;;;

PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
     _t_a_r_g_e_t   expects the texture resource to which the texture function
              definition is to be bound.  There are three appropriate
              resources, TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____0000 , TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEETTTTAAAAIIIILLLL and TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIIDDDDLLLLEEEE.

     _i_n_d_e_x    expects the name of the texture function that is being bound.
              Name is the index passed to tttteeeexxxxddddeeeeffff2222dddd when the texture function
              was defined.

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     Texture coordinates, _s,_t,_u may be specified at geometry vertices,
     similarly to color, depth, and vertex normals.  The texture coordinates
     are interpolated from the values specified at the vertices for each
     screen pixel touched by the geometry.  A texture function maps the
     texture coordinates _s,_t, or _s,_t,_u, corresponding to a screen pixel into
     _n_c values, called texture function outputs, using an _i_m_a_g_e and a set of
     properties. The texture function outputs may be translated with a texture
     look-up table.  The texture function outputs are used by the texture
     environment function to modify the screen pixel color.

     tttteeeexxxxddddeeeeffff2222dddd and tttteeeexxxxddddeeeeffff3333dddd define a texture function and tttteeeexxxxbbbbiiiinnnndddd selects which
     texture function definition to use.  The texture environment function is
     defined by tttteeeevvvvddddeeeeffff and selected by tttteeeevvvvbbbbiiiinnnndddd. The texture look-up table is
     defined by ttttlllluuuuttttddddeeeeffff and selected by ttttlllluuuuttttbbbbiiiinnnndddd. The texture coordinates are
     specified with the tttt family of commands.

     By default texture function definition 0 is bound to TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____0000.
     Texture mapping is enabled when an texture function definition other than
     0 is bound to TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____0000, and a texture environment definition other
     than 0 is bound to TTTTVVVV____EEEENNNNVVVV0000.  (See tttteeeevvvvbbbbiiiinnnndddd.)  If the texture bound to
     TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____0000, uses a detail enhancing magnification algorithm, the
     texture bound to TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEETTTTAAAAIIIILLLL, is used in that calculation. If no
     texture is bound to TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEETTTTAAAAIIIILLLL, and the magnification algorithm
     reqires a detail texture results are undefined.

     TTTTXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIIDDDDLLLLEEEE can be used in the following way to control texture
     memory management.  The N most recently loaded (a texbind that required a
     load) textures that fit in texture memory are tracked by the GL.  If
     texture memory is full and a new texture is bound, the texture that has
     been in texture memory the longest replaced by the new texture. If the
     user wishes some other texture to be replaced, he can idle that texture
     first and the new texture will use the space vacated by the idled
     texture. A simple example is the case where two textures can fit in
     texture memory and user wishes to keep one texture, texture A, in memory
     always and cycle through three other textures, B, C, D, of which only one



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tttteeeexxxxbbbbiiiinnnndddd((((3333GGGG))))                                                        tttteeeexxxxbbbbiiiinnnndddd((((3333GGGG))))



     will fit. To avoid replacing texture A, the user can idle texture B after
     primitives are drawn with it, and when C is bound (and loaded), it will
     take the space vacated by B, and leave the texture A alone.

SSSSEEEEEEEE AAAALLLLSSSSOOOO
     t, tevbind, tevdef, texdef2d

NNNNOOOOTTTTEEEESSSS
     IRIS-4D G, GT, and GTX models, and the Personal Iris, do not support
     texture mapping.  tttteeeexxxxbbbbiiiinnnndddd is ignored by these machines.  The Iris Indy,
     Indigo Entry, and XL support texture mapping except for lines.  Use
     ggggeeeettttggggddddeeeesssscccc to determine whether texture mapping is supported.

     tttteeeexxxxbbbbiiiinnnndddd cannot be used while mmmmmmmmooooddddeeee is MMMMSSSSIIIINNNNGGGGLLLLEEEE.









































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