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<STRONG>NAME</STRONG>
<STRONG>glHint</STRONG> - specify implementation-specific hints
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glHint</STRONG>( GLenum <EM>target</EM>,
GLenum <EM>mode</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>target</EM> Specifies a symbolic constant indicating the
behavior to be controlled. <STRONG>GL_FOG_HINT</STRONG>,
<STRONG>GL_LINE_SMOOTH_HINT</STRONG>, <STRONG>GL_PERSPECTIVE_CORRECTION_HINT</STRONG>,
<STRONG>GL_POINT_SMOOTH_HINT</STRONG>, and <STRONG>GL_POLYGON_SMOOTH_HINT</STRONG> are
accepted.
<EM>mode</EM> Specifies a symbolic constant indicating the desired
behavior. <STRONG>GL_FASTEST</STRONG>, <STRONG>GL_NICEST</STRONG>, and <STRONG>GL_DONT_CARE</STRONG>
are accepted.
<STRONG>DESCRIPTION</STRONG>
Certain aspects of GL behavior, when there is room for
interpretation, can be controlled with hints. A hint is
specified with two arguments. <EM>target</EM> is a symbolic constant
indicating the behavior to be controlled, and <EM>mode</EM> is
another symbolic constant indicating the desired behavior.
The initial value for each <EM>target</EM> is <STRONG>GL_DONT_CARE</STRONG>. <EM>mode</EM> can
be one of the following:
<STRONG>GL_FASTEST</STRONG> The most efficient option should be
chosen.
<STRONG>GL_NICEST</STRONG> The most correct, or highest quality,
option should be chosen.
<STRONG>GL_DONT_CARE</STRONG> No preference.
Though the implementation aspects that can be hinted are
well defined, the interpretation of the hints depends on the
implementation. The hint aspects that can be specified with
<EM>target</EM>, along with suggested semantics, are as follows:
<STRONG>GL_FOG_HINT</STRONG> Indicates the accuracy of fog
calculation. If per-pixel fog
calculation is not efficiently supported
by the GL implementation, hinting
<STRONG>GL_DONT_CARE</STRONG> or <STRONG>GL_FASTEST</STRONG> can result in
per-vertex calculation of fog effects.
<STRONG>GL_LINE_SMOOTH_HINT</STRONG> Indicates the sampling quality of
antialiased lines. If a larger filter
function is applied, hinting <STRONG>GL_NICEST</STRONG>
can result in more pixel fragments being
generated during rasterization,
<STRONG>GL_PERSPECTIVE_CORRECTION_HINT</STRONG>
Indicates the quality of color and
texture coordinate interpolation. If
perspective-corrected parameter
interpolation is not efficiently
supported by the GL implementation,
hinting <STRONG>GL_DONT_CARE</STRONG> or <STRONG>GL_FASTEST</STRONG> can
result in simple linear interpolation of
colors and/or texture coordinates.
<STRONG>GL_POINT_SMOOTH_HINT</STRONG>
Indicates the sampling quality of
antialiased points. If a larger filter
function is applied, hinting <STRONG>GL_NICEST</STRONG>
can result in more pixel fragments being
generated during rasterization,
<STRONG>GL_POLYGON_SMOOTH_HINT</STRONG>
Indicates the sampling quality of
antialiased polygons. Hinting <STRONG>GL_NICEST</STRONG>
can result in more pixel fragments being
generated during rasterization, if a
larger filter function is applied.
<STRONG>NOTES</STRONG>
The interpretation of hints depends on the implementation.
Some implementations ignore <STRONG>glHint</STRONG> settings.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_ENUM</STRONG> is generated if either <EM>target</EM> or <EM>mode</EM> is not
an accepted value.
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glHint</STRONG> is executed
between the execution of <STRONG>glBegin</STRONG> and the corresponding
execution of <STRONG>glEnd</STRONG>.
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