glHint — specify implementation-specific hints
void glHint( | GLenum target, |
GLenum mode) ; |
target
Specifies a symbolic constant indicating the behavior to be controlled. GL_FRAGMENT_SHADER_DERIVATIVE_HINT
, and GL_GENERATE_MIPMAP_HINT
are accepted.
mode
Specifies a symbolic constant indicating the desired behavior. GL_FASTEST
, GL_NICEST
, and GL_DONT_CARE
are accepted.
Certain aspects of GL behavior, when there is room for interpretation, can be controlled with hints. A hint is specified with two arguments. target
is a symbolic constant indicating the behavior to be controlled, and mode
is another symbolic constant indicating the desired behavior. The initial value for each target
is GL_DONT_CARE
. mode
can be one of the following:
GL_FASTEST
The most efficient option should be chosen.
GL_NICEST
The most correct, or highest quality, option should be chosen.
GL_DONT_CARE
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 target
, along with suggested semantics, are as follows:
GL_FRAGMENT_SHADER_DERIVATIVE_HINT
Indicates the accuracy of the derivative calculation for the GL shading language fragment processing built-in functions: dFdx
, dFdy
, and fwidth
.
GL_GENERATE_MIPMAP_HINT
Indicates the quality of filtering when generating mipmap images with glGenerateMipmap.
The interpretation of hints depends on the implementation. Some implementations ignore glHint
settings.
GL_INVALID_ENUM
is generated if either target
or mode
is not an accepted value.
OpenGL ES API Version | |||
---|---|---|---|
Function Name | 2.0 | 3.0 | 3.1 |
glHint | ✔ | ✔ | ✔ |
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