HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 14
glGet with argument GL_ALPHA_TEST_REF
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A glAlphaFunc glAlphaFunc operates on all pixel write operations, including those resulting from the scan conversion of points, lines, polygons, and bitmaps, and from pixel draw and copy operations. glAlphaFunc does not affect screen-clear operations. Notes Alpha testing is performed only in RGBA mode. Errors • GL_INVALID_ENUM is generated if func is not an accepted value. • GL_INVALID_OPERATION is generated if glAlphaFunc is executed between the execution of glBegin and the corresponding execution of glEnd. Associated Gets glGet with argument GL_ALPHA_TEST_FUNC glGet with argument GL_ALPHA_TEST_REF glIsEnabled with argument GL_ALPHA_TEST See Also glBlendFunc, glClear, glDepthFunc, glEnable, glStencilFunc 14 Chapter 1
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 |
 |
A
glAlphaFunc
Chapter 1
14
glAlphaFunc operates on all pixel write operations, including those resulting from the
scan conversion of points, lines, polygons, and bitmaps, and from pixel draw and copy
operations. glAlphaFunc does not affect screen-clear operations.
Notes
Alpha testing is performed only in RGBA mode.
Errors
•
GL_INVALID_ENUM is generated if
func
is not an accepted value.
•
GL_INVALID_OPERATION is generated if glAlphaFunc is executed between the
execution of glBegin and the corresponding execution of glEnd.
Associated Gets
glGet with argument GL_ALPHA_TEST_FUNC
glGet with argument GL_ALPHA_TEST_REF
glIsEnabled with argument GL_ALPHA_TEST
See Also
glBlendFunc,
glClear,
glDepthFunc,
glEnable,
glStencilFunc