glClearAccum - specify clear values for the accumulation buffer
void glClearAccum( GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha )
red, green, blue, alpha Specify the red, green, blue, and alpha values used when the accumulation buffer is cleared. The default values are all zero.
glClearAccum specifies the red, green, blue, and alpha values used by glClear to clear the accumulation buffer. Values specified by glClearAccum are clamped to the range [-1,1].
GL_INVALID_OPERATION is generated if glClearAccum is executed between the execution of glBegin and the corresponding execution of glEnd.
glGet with argument GL_ACCUM_CLEAR_VALUE
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Fri Dec 6 11:18:03 EST 1996
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