Index for Section 3G

Alphabetical listing for G

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glClipPlane(3G)
NAME
  glClipPlane - specify a plane against which all geometry is clipped

SYNOPSIS
  void glClipPlane(
	  GLenum plane,
	  const GLdouble *equation );

PARAMETERS
  plane
      Specifies which clipping plane is being positioned. Symbolic names of
      the form GL_CLIP_PLANEi, where i is an integer between 0 and
      GL_MAX_CLIP_PLANES-1, are accepted.

  equation
      Specifies the address of an array of four double-precision floating-
      point values. These values are interpreted as a plane equation.

DESCRIPTION
  Geometry is always clipped against the boundaries of a six-plane frustum in
  x, y, and z.	glClipPlane allows the specification of additional planes,
  not necessarily perpendicular to the x, y, or z axis, against which all
  geometry is clipped. To determine the maximum number of additional clipping
  planes, call glGetIntegerv() with argument GL_MAX_CLIP_PLANES. All
  implementations support at least six such clipping planes.  Because the
  resulting clipping region is the intersection of the defined half-spaces,
  it is always convex.

  glClipPlane() specifies a half-space using a four-component plane equation.
  When glClipPlane() is called, equation is transformed by the inverse of the
  modelview matrix and stored in the resulting eye coordinates. Subsequent
  changes to the modelview matrix have no effect on the stored plane-equation
  components. If the dot product of the eye coordinates of a vertex with the
  stored plane equation components is positive or zero, the vertex is in with
  respect to that clipping plane. Otherwise, it is out.

  To enable and disable clipping planes, call glEnable() and glDisable() with
  the argument GL_CLIP_PLANEi, where i is the plane number.

  All clipping planes are initially defined as (0, 0, 0, 0) in eye
  coordinates and are disabled.

NOTES
  It is always the case that GL_CLIP_PLANEi = GL_CLIP_PLANE0+i.

ERRORS
  GL_INVALID_ENUM is generated if plane is not an accepted value.

  GL_INVALID_OPERATION is generated if glClipPlane() is executed between the
  execution of glBegin() and the corresponding execution of glEnd().

ASSOCIATED GETS
       glGetClipPlane()
       glIsEnabled() with argument GL_CLIP_PLANEi

SEE ALSO
  glEnable(3)

Index for Section 3G

Alphabetical listing for G

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