IRIX Base Documentation 2002 November/SGI IRIX Base Documentation 2002 November.iso/usr/share/catman/g_man/cat3/OpenGL/glgettexlevelparameter.z/glgettexlevelparameter

Text File | 2002-10-03 | 15.9 KB | 200 lines

ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))     OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee     ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))



NNNNAAAAMMMMEEEE
     ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrrffffvvvv,,,, ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrriiiivvvv - return texture
     parameter values for a specific level of detail


CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
     void ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrrffffvvvv( GLenum _t_a_r_g_e_t,
                                    GLint _l_e_v_e_l,
                                    GLenum _p_n_a_m_e,
                                    GLfloat *_p_a_r_a_m_s )
     void ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrriiiivvvv( GLenum _t_a_r_g_e_t,
                                    GLint _l_e_v_e_l,
                                    GLenum _p_n_a_m_e,
                                    GLint *_p_a_r_a_m_s )


PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
     _t_a_r_g_e_t  Specifies the symbolic name of the target texture, either
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____1111DDDD, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD, GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____1111DDDD,
             GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD, GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD, or
             GGGGLLLL____DDDDEEEETTTTAAAAIIIILLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD____SSSSGGGGIIIISSSS.

     _l_e_v_e_l   Specifies the level-of-detail number of the desired image.  Level
             0 is the base image level.  Level n is the nth mipmap reduction
             image.

     _p_n_a_m_e   Specifies the symbolic name of a texture parameter.
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____WWWWIIIIDDDDTTTTHHHH, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____HHHHEEEEIIIIGGGGHHHHTTTT, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEEPPPPTTTTHHHH,
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIINNNNTTTTEEEERRRRNNNNAAAALLLL____FFFFOOOORRRRMMMMAAAATTTT, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____BBBBOOOORRRRDDDDEEEERRRR,
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____RRRREEEEDDDD____SSSSIIIIZZZZEEEE, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____GGGGRRRREEEEEEEENNNN____SSSSIIIIZZZZEEEE, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____BBBBLLLLUUUUEEEE____SSSSIIIIZZZZEEEE,
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____AAAALLLLPPPPHHHHAAAA____SSSSIIIIZZZZEEEE, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____LLLLUUUUMMMMIIIINNNNAAAANNNNCCCCEEEE____SSSSIIIIZZZZEEEE, and
             GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIINNNNTTTTEEEENNNNSSSSIIIITTTTYYYY____SSSSIIIIZZZZEEEE are accepted.

     _p_a_r_a_m_s  Returns the requested data.

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr returns in _p_a_r_a_m_s texture parameter values for a
     specific level-of-detail value, specified as _l_e_v_e_l.  _t_a_r_g_e_t defines the
     target texture, either GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____1111DDDD, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD, GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD,
     GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____1111DDDD, GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD, GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD, or
     GGGGLLLL____DDDDEEEETTTTAAAAIIIILLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD____SSSSGGGGIIIISSSS.

     GGGGLLLL____MMMMAAAAXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____SSSSIIIIZZZZEEEE, and GGGGLLLL____MMMMAAAAXXXX____3333DDDD____TTTTEEEEXXXXTTTTUUUURRRREEEE____SSSSIIIIZZZZEEEE are not really
     descriptive enough.  It has to report the largest square texture image
     that can be accommodated with mipmaps and borders, but a long skinny
     texture, or a texture without mipmaps and borders, may easily fit in
     texture memory. The proxy targets allow the user to more accurately query
     whether the GL can accommodate a texture of a given configuration.  If
     the texture cannot be accommodated, the texture state variables, which
     may be queried with ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr, are set to 0.  If the texture
     can be accommodated, the texture state values will be set as they would
     be set for a non-proxy target.



                                                                        PPPPaaaaggggeeee 1111






ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))     OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee     ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))



     _p_n_a_m_e specifies the texture parameter whose value or values will be
     returned.

     The accepted parameter names are as follows:

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____WWWWIIIIDDDDTTTTHHHH
               _p_a_r_a_m_s returns a single value, the width of the texture image.
               This value includes the border of the texture image. The
               initial value is 0.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____HHHHEEEEIIIIGGGGHHHHTTTT
               _p_a_r_a_m_s returns a single value, the height of the texture image.
               This value includes the border of the texture image. The
               initial value is 0.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEEPPPPTTTTHHHH
               _p_a_r_a_m_s returns a single value, the depth of the texture image.
               This value includes the border of the texture image. The
               initial value is 0.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIINNNNTTTTEEEERRRRNNNNAAAALLLL____FFFFOOOORRRRMMMMAAAATTTT
               _p_a_r_a_m_s returns a single value, the internal format of the
               texture image.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____BBBBOOOORRRRDDDDEEEERRRR
               _p_a_r_a_m_s returns a single value, the width in pixels of the
               border of the texture image. The initial value is 0.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____RRRREEEEDDDD____SSSSIIIIZZZZEEEE,

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____GGGGRRRREEEEEEEENNNN____SSSSIIIIZZZZEEEE,

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____BBBBLLLLUUUUEEEE____SSSSIIIIZZZZEEEE,

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____AAAALLLLPPPPHHHHAAAA____SSSSIIIIZZZZEEEE,

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____LLLLUUUUMMMMIIIINNNNAAAANNNNCCCCEEEE____SSSSIIIIZZZZEEEE,

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIINNNNTTTTEEEENNNNSSSSIIIITTTTYYYY____SSSSIIIIZZZZEEEE
               The internal storage resolution of an individual component.
               The resolution chosen by the GL will be a close match for the
               resolution requested by the user with the component argument of
               ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee1111DDDD, ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee2222DDDD, ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee3333DDDD, ggggllllCCCCooooppppyyyyTTTTeeeexxxxIIIImmmmaaaaggggeeee1111DDDD, and
               ggggllllCCCCooooppppyyyyTTTTeeeexxxxIIIImmmmaaaaggggeeee2222DDDD. The initial value is 0.

NNNNOOOOTTTTEEEESSSS
     If an error is generated, no change is made to the contents of _p_a_r_a_m_s.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____IIIINNNNTTTTEEEERRRRNNNNAAAALLLL____FFFFOOOORRRRMMMMAAAATTTT is available only if the GL version is 1.1 or
     greater. In version 1.0, use GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOMMMMPPPPOOOONNNNEEEENNNNTTTTSSSS instead.





                                                                        PPPPaaaaggggeeee 2222






ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))     OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee     ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr((((3333GGGG))))



     GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____1111DDDD and GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____2222DDDD are available only if the GL
     version is 1.1 or greater.

     GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD, GGGGLLLL____PPPPRRRROOOOXXXXYYYY____TTTTEEEEXXXXTTTTUUUURRRREEEE____3333DDDD, and GGGGLLLL____TTTTEEEEXXXXTTTTUUUURRRREEEE____DDDDEEEEPPPPTTTTHHHH are available
     only if the GL version is 1.2 or greater.

EEEERRRRRRRROOOORRRRSSSS
     GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____EEEENNNNUUUUMMMM is generated if _t_a_r_g_e_t or _p_n_a_m_e is not an accepted value.

     GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____VVVVAAAALLLLUUUUEEEE is generated if _l_e_v_e_l is less than 0.

     GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____VVVVAAAALLLLUUUUEEEE may be generated if _l_e_v_e_l is greater than log  _m_a_x,
                                                                   2
     where _m_a_x is the returned value of GGGGLLLL____MMMMAAAAXXXX____TTTTEEEEXXXXTTTTUUUURRRREEEE____SSSSIIIIZZZZEEEE.

     GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ggggllllGGGGeeeettttTTTTeeeexxxxLLLLeeeevvvveeeellllPPPPaaaarrrraaaammmmeeeetttteeeerrrr is executed
     between the execution of ggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of
     ggggllllEEEEnnnndddd.


SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ggggllllGGGGeeeettttTTTTeeeexxxxPPPPaaaarrrraaaammmmeeeetttteeeerrrr, ggggllllCCCCooooppppyyyyTTTTeeeexxxxIIIImmmmaaaaggggeeee1111DDDD, ggggllllCCCCooooppppyyyyTTTTeeeexxxxIIIImmmmaaaaggggeeee2222DDDD,
     ggggllllCCCCooooppppyyyyTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee1111DDDD, ggggllllCCCCooooppppyyyyTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee2222DDDD, ggggllllCCCCooooppppyyyyTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee3333DDDD, ggggllllTTTTeeeexxxxEEEEnnnnvvvv,
     ggggllllTTTTeeeexxxxGGGGeeeennnn, ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee1111DDDD, ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee2222DDDD, ggggllllTTTTeeeexxxxIIIImmmmaaaaggggeeee3333DDDD, ggggllllTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee1111DDDD,
     ggggllllTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee2222DDDD, ggggllllTTTTeeeexxxxSSSSuuuubbbbIIIImmmmaaaaggggeeee3333DDDD, ggggllllTTTTeeeexxxxPPPPaaaarrrraaaammmmeeeetttteeeerrrr































                                                                        PPPPaaaaggggeeee 3333