glDepthFunc function
The glDepthFunc function specifies the value used for depth-buffer comparisons.
Syntax
void WINAPI glDepthFunc(
GLenum func
);
Parameters
-
func
-
Specifies the depth-comparison function. The following symbolic constants are accepted.
Value Meaning - GL_NEVER
Never passes. - GL_LESS
Passes if the incoming z value is less than the stored z value. This is the default value. - GL_LEQUAL
Passes if the incoming z value is less than or equal to the stored z value. - GL_EQUAL
Passes if the incoming z value is equal to the stored z value. - GL_GREATER
Passes if the incoming z value is greater than the stored z value. - GL_NOTEQUAL
Passes if the incoming z value is not equal to the stored z value. - GL_GEQUAL
Passes if the incoming z value is greater than or equal to the stored z value. - GL_ALWAYS
Always passes.
Return value
This function does not return a value.
Error codes
The following error code can be retrieved by the glGetError function.
| Name | Meaning |
|---|---|
|
The function was called between a call to glBegin and the corresponding call to glEnd. |
Remarks
The glDepthFunc function specifies the function used to compare each incoming pixel z value with the z value present in the depth buffer. The comparison is performed only if depth testing is enabled. (See glEnable with the argument GL_DEPTH_TEST.)
Initially, depth testing is disabled.
The following functions retrieve information related to glDepthFunc:
glGet with argument GL_DEPTH_FUNC
glIsEnabled with argument GL_DEPTH_TEST
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows 2000 Professional [desktop apps only] |
| Minimum supported server |
Windows 2000 Server [desktop apps only] |
| Header |
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| Library |
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| DLL |
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