GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD, GGGGLLLLUUUU____UUUU____SSSSTTTTEEEEPPPP, GGGGLLLLUUUU____VVVV____SSSSTTTTEEEEPPPP, or GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____MMMMOOOODDDDEEEE.
_v_a_l_u_e Specifies the value of the indicated property. It may be a
numeric value, or one of GGGGLLLLUUUU____OOOOUUUUTTTTLLLLIIIINNNNEEEE____PPPPOOOOLLLLYYYYGGGGOOOONNNN, GGGGLLLLUUUU____FFFFIIIILLLLLLLL,
or GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____TTTTEEEESSSSSSSSEEEELLLLLLLLAAAATTTTOOOORRRR.
DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
gggglllluuuuNNNNuuuurrrrbbbbssssPPPPrrrrooooppppeeeerrrrttttyyyy is used to control properties stored in a NURBS object.
These properties affect the way that a NURBS curve is rendered. The
accepted values for _p_r_o_p_e_r_t_y are as follows:
GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____MMMMOOOODDDDEEEE _v_a_l_u_e should be set to be either GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____RRRREEEENNNNDDDDEEEERRRREEEERRRR or
GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____TTTTEEEESSSSSSSSEEEELLLLLLLLAAAATTTTOOOORRRR. When set to GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____RRRREEEENNNNDDDDEEEERRRREEEERRRR,
NURBS objects are tessellated into OpenGL primitives and
sent to the pipeline for rendering. When set to
GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____TTTTEEEESSSSSSSSEEEELLLLLLLLAAAATTTTOOOORRRR, NURBS objects are tessellated into
OpenGL primitives but the vertices, normals, colors,
and/or textures are retrieved back through a callback
interface (see gggglllluuuuNNNNuuuurrrrbbbbssssCCCCaaaallllllllbbbbaaaacccckkkk). This allows the user to
cache the tessellated results for further processing. The
initial value is GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____RRRREEEENNNNDDDDEEEERRRREEEERRRR.
Specifies how a NURBS surface should be tessellated.
_v_a_l_u_e may be one of GGGGLLLLUUUU____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH, GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR,
GGGGLLLLUUUU____DDDDOOOOMMMMAAAAIIIINNNN____DDDDIIIISSSSTTTTAAAANNNNCCCCEEEE, GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH, or
GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR. When set to GGGGLLLLUUUU____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH,
the surface is rendered so that the maximum length, in
pixels, of the edges of the tessellation polygons is no
greater than what is specified by GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____TTTTOOOOLLLLEEEERRRRAAAANNNNCCCCEEEE.
GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR specifies that the surface is
rendered in such a way that the value specified by
GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____TTTTOOOOLLLLEEEERRRRAAAANNNNCCCCEEEE describes the maximum distance,
in pixels, between the tessellation polygons and the
surfaces they approximate.
GGGGLLLLUUUU____DDDDOOOOMMMMAAAAIIIINNNN____DDDDIIIISSSSTTTTAAAANNNNCCCCEEEE allows users to specify, in parametric
coordinates, how many sample points per unit length are
taken in _u, _v direction.
GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH is similar to GGGGLLLLUUUU____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH
except that it is view independent, that is, the surface
is rendered so that the maximum length, in object space,
of edges of the tessellation polygons is no greater than
what is specified by GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____TTTTOOOOLLLLEEEERRRRAAAANNNNCCCCEEEE.
GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR is similar to
GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR except that it is view independent,
that is, the surface is rendered in such a way that the
value specified by GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____TTTTOOOOLLLLEEEERRRRAAAANNNNCCCCEEEE describes the
maximum distance, in object space, between the
tessellation polygons and the surfaces they approximate.
The initial value of GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD is
Specifies the maximum length, in pixels or in object space
length unit, to use when the sampling method is set to
GGGGLLLLUUUU____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH or GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH. The NURBS code
is conservative when rendering a curve or surface, so the
actual length can be somewhat shorter. The initial value
Specifies the maximum distance, in pixels or in object
space length unit, to use when the sampling method is
GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR or GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR. The
initial value is 0.5.
GGGGLLLLUUUU____UUUU____SSSSTTTTEEEEPPPP Specifies the number of sample points per unit length
taken along the _u axis in parametric coordinates. It is
needed when GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD is set to
GGGGLLLLUUUU____DDDDOOOOMMMMAAAAIIIINNNN____DDDDIIIISSSSTTTTAAAANNNNCCCCEEEE. The initial value is 100.
GGGGLLLLUUUU____VVVV____SSSSTTTTEEEEPPPP Specifies the number of sample points per unit length
taken along the _v axis in parametric coordinate. It is
needed when GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD is set to
GGGGLLLLUUUU____DDDDOOOOMMMMAAAAIIIINNNN____DDDDIIIISSSSTTTTAAAANNNNCCCCEEEE. The initial value is 100.
surface is rendered as a set of polygons. When _v_a_l_u_e is
set to GGGGLLLLUUUU____OOOOUUUUTTTTLLLLIIIINNNNEEEE____PPPPOOOOLLLLYYYYGGGGOOOONNNN, the NURBS library draws only
the outlines of the polygons created by tessellation. When
_v_a_l_u_e is set to GGGGLLLLUUUU____OOOOUUUUTTTTLLLLIIIINNNNEEEE____PPPPAAAATTTTCCCCHHHH just the outlines of
patches and trim curves defined by the user are drawn.
When GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____MMMMOOOODDDDEEEE is set to be GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____TTTTEEEESSSSSSSSEEEELLLLLLLLAAAATTTTOOOORRRR,
_v_a_l_u_e defines how a NURBS surface should be tessellated.
When GGGGLLLLUUUU____DDDDIIIISSSSPPPPLLLLAAAAYYYY____MMMMOOOODDDDEEEE is set to GGGGLLLLUUUU____FFFFIIIILLLLLLLL or
GGGGLLLLUUUU____OOOOUUUUTTTTLLLLIIIINNNNEEEE____PPPPOOOOLLLLYYYYGGGGOOOONNNN, the NURBS surface is tessellated into
OpenGL triangle primitives which can be retrieved back
through callback functions. If GGGGLLLLUUUU____DDDDIIIISSSSPPPPLLLLAAAAYYYY____MMMMOOOODDDDEEEE is set to
GGGGLLLLUUUU____OOOOUUUUTTTTLLLLIIIINNNNEEEE____PPPPAAAATTTTCCCCHHHH, only the outlines of the patches and
trim curves are generated as a sequence of line strips
which can be retrieved back through callback functions.
The initial value is GGGGLLLLUUUU____FFFFIIIILLLLLLLL.
GGGGLLLLUUUU____CCCCUUUULLLLLLLLIIIINNNNGGGG _v_a_l_u_e is a boolean value that, when set to GGGGLLLL____TTTTRRRRUUUUEEEE,
indicates that a NURBS curve should be discarded prior to
tessellation if its control points lie outside the current
viewport. The initial value is GGGGLLLL____FFFFAAAALLLLSSSSEEEE.
_v_a_l_u_e is a boolean value. When set to GGGGLLLL____TTTTRRRRUUUUEEEE, the NURBS
code downloads the projection matrix, the modelview
matrix, and the viewport from the GL server to compute
sampling and culling matrices for each NURBS curve that is
rendered. Sampling and culling matrices are required to
determine the tessellation of a NURBS surface into line
segments or polygons and to cull a NURBS surface if it
lies outside the viewport.
If this mode is set to GGGGLLLL____FFFFAAAALLLLSSSSEEEE, then the program needs to
provide a projection matrix, a modelview matrix, and a
viewport for the NURBS renderer to use to construct
sampling and culling matrices. This can be done with the
gggglllluuuuLLLLooooaaaaddddSSSSaaaammmmpppplllliiiinnnnggggMMMMaaaattttrrrriiiicccceeeessss function. This mode is initially
set to GGGGLLLL____TTTTRRRRUUUUEEEE. Changing it from GGGGLLLL____TTTTRRRRUUUUEEEE to GGGGLLLL____FFFFAAAALLLLSSSSEEEE does
not affect the sampling and culling matrices until
gggglllluuuuLLLLooooaaaaddddSSSSaaaammmmpppplllliiiinnnnggggMMMMaaaattttrrrriiiicccceeeessss is called.
NNNNOOOOTTTTEEEESSSS
If GGGGLLLLUUUU____AAAAUUUUTTTTOOOO____LLLLOOOOAAAADDDD____MMMMAAAATTTTRRRRIIIIXXXX is true, sampling and culling may be executed
incorrectly if NURBS routines are compiled into a display list.
A _p_r_o_p_e_r_t_y of GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____TTTTOOOOLLLLEEEERRRRAAAANNNNCCCCEEEE, GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD, GGGGLLLLUUUU____UUUU____SSSSTTTTEEEEPPPP,
or GGGGLLLLUUUU____VVVV____SSSSTTTTEEEEPPPP, or a _v_a_l_u_e of GGGGLLLLUUUU____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH, GGGGLLLLUUUU____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR,
GGGGLLLLUUUU____DDDDOOOOMMMMAAAAIIIINNNN____DDDDIIIISSSSTTTTAAAANNNNCCCCEEEE are only available if the GLU version is 1.1 or
greater. They are not valid parameters in GLU 1.0.
gggglllluuuuGGGGeeeettttSSSSttttrrrriiiinnnngggg can be used to determine the GLU version.
GGGGLLLLUUUU____NNNNUUUURRRRBBBBSSSS____MMMMOOOODDDDEEEE is only availble if the GLU version is 1.3 or greater.
The GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAATTTTHHHH____LLLLEEEENNNNGGGGTTTTHHHH and GGGGLLLLUUUU____OOOOBBBBJJJJEEEECCCCTTTT____PPPPAAAARRRRAAAAMMMMEEEETTTTRRRRIIIICCCC____EEEERRRRRRRROOOORRRR values for the
GGGGLLLLUUUU____SSSSAAAAMMMMPPPPLLLLIIIINNNNGGGG____MMMMEEEETTTTHHHHOOOODDDD property are only available if the GLU version is 1.3
