glStencilFunc Function

GL_APICALL void GL_APIENTRY glStencilFunc(
     GLenum func,
     GLint ref,
     GLuint mask
);

	Name	Description
in	func	Comparison function
in	ref	Reference value
in	mask	Mask value

No values are returned.

Configures the comparison function, reference value, and mask value used by the stencil test.

You can set func to GL_NEVER, GL_ALWAYS, GL_LESS, GL_LEQUAL, GL_EQUAL, GL_GREATER, GL_GEQUAL, or GL_NOTEQUAL. Set ref to the reference value. Set mask to the mask value.

Given a stencil buffer value of stencil, the stencil test passes or fails according to the following conditions specified by func.

GL_NEVER	The stencil test always fails.
GL_ALWAYS	The stencil test always passes.
GL_LESS	Passes when (ref & mask) < (stencil & mask).
GL_LEQUAL	Passes when (ref & mask) <= (stencil & mask).
GL_EQUAL	Passes when (ref & mask) == (stencil & mask).
GL_GREATER	Passes when (ref & mask) > (stencil & mask).
GL_GEQUAL	Passes when (ref & mask) >= (stencil & mask).
GL_NOTEQUAL	Passes when (ref & mask) != (stencil & mask).

This function generates the following errors.

GL_INVALID_ENUM	The func argument was set to an invalid value.
GL_INVALID_OPERATION	This function was called without any command-list objects bound.

2010/01/07

Initial version.