glHint function

Artikkel
12/11/2020

The glHint function specifies implementation-specific hints.

Syntax

void WINAPI glHint(
   GLenum target,
   GLenum mode
);

Parameters

target

A symbolic constant indicating the behavior to be controlled. The following symbolic constants, along with suggested semantics, are accepted.

Value	Meaning
GL_FOG_HINT	Indicates the accuracy of fog calculation. If per-pixel fog calculation is not efficiently supported by the OpenGL implementation, hinting GL_DONT_CARE or GL_FASTEST can result in per-vertex calculation of fog effects.
GL_LINE_SMOOTH_HINT	Indicates the sampling quality of antialiased lines. Hinting GL_NICEST can result in more pixel fragments being generated during rasterization, if a larger filter function is applied.
GL_PERSPECTIVE_CORRECTION_HINT	Indicates the quality of color and texture coordinate interpolation. If perspective-corrected parameter interpolation is not efficiently supported by the OpenGL implementation, hinting GL_DONT_CARE or GL_FASTEST can result in simple linear interpolation of colors and/or texture coordinates.
GL_POINT_SMOOTH_HINT	Indicates the sampling quality of antialiased points. Hinting GL_NICEST can result in more pixel fragments being generated during rasterization, if a larger filter function is applied.
GL_POLYGON_SMOOTH_HINT	Indicates the sampling quality of antialiased polygons. Hinting GL_NICEST can result in more pixel fragments being generated during rasterization, if a larger filter function is applied.

mode

A symbolic constant indicating the desired behavior. The following symbolic constants are accepted.

Value	Meaning
GL_FASTEST	The most efficient option should be chosen.
GL_NICEST	The most correct, or highest quality, option should be chosen.
GL_DONT_CARE	The client doesn't have a preference.

Return value

This function does not return a value.

Error codes

The following error codes can be retrieved by the glGetError function.

Name	Meaning
GL_INVALID_ENUM	target or mode was not an accepted value.
GL_INVALID_OPERATION	The function was called between a call to glBegin and the corresponding call to glEnd.

Remarks

When there is room for interpretation, you can control certain aspects of OpenGL behavior with hints. You specify a hint with two arguments. The target parameter is a symbolic constant indicating the behavior to be controlled, and mode is another symbolic constant indicating the desired behavior.

Though the implementation aspects that can be hinted are well defined, the interpretation of the hints depends on the implementation.

The glHint function can be ignored.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	Gl.h
Library	Opengl32.lib
DLL	Opengl32.dll

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