glDepthFunc
[New
- Windows 95, OEM Service Release 2]
The glDepthFunc
function specifies the value used for depth-buffer comparisons.
void glDepthFunc(
|
GLenum func |
|
|
); |
|
Parameters
func
The
depth-comparison function. The following symbolic constants are accepted.
|
Symbolic
Constant |
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_EQUAL |
Passes if
the incoming z value is equal to the stored z value. |
|
GL_LEQUAL |
Passes if
the incoming z value is less than or 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. |
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
Error Codes
The following
are the error codes generated and their conditions.
|
Error
Code |
Condition |
|
GL_INVALID_ENUM
|
func was not an accepted value. |
|
GL_INVALID_OPERATION
|
glDepthFunc was called between a call to glBegin and the
corresponding call to glEnd. |
See Also