Index for Section 3G

Alphabetical listing for G

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glEvalPoint(3G)
NAME
  glEvalPoint, glEvalPoint1, glEvalPoint2 - generate and evaluate a single
  point in a mesh

SYNOPSIS
  void glEvalPoint1(
	  GLint i );

  void glEvalPoint2(
	  GLint i,
	  GLint j );

PARAMETERS
  i   Specifies the integer value for grid domain variable i.

  j   Specifies the integer value for grid domain variable j (glEvalPoint2()
      only).

DESCRIPTION
  glMapGrid() and glEvalMesh() are used in tandem to efficiently generate and
  evaluate a series of evenly spaced map domain values.	 glEvalPoint() can be
  used to evaluate a single grid point in the same gridspace that is
  traversed by glEvalMesh(). Calling glEvalPoint1() is equivalent to calling

       glEvalCoord1( i . DELTA u + u[1] );

  where

       DELTA u = ( u[2] - u[1] ) / n

  and n, u[1], and u[2] are the arguments to the most recent glMapGrid1()
  command. The one absolute numeric requirement is that if i=n, then the
  value computed from i . DELTA u + u[1] is exactly u[2].

  In the two-dimensional case, glEvalPoint2, let

       DELTA u =  u[2] - u[1] ) / n

       DELTA v = ( v[2] - v[1] ) / m,

  where n, u[1], u[2], m, v[1], and v[2] are the arguments to the most recent
  glMapGrid2() command. Then the glEvalPoint2() command is equivalent to
  calling

       glEvalCoord2( i . DELTA u + u[1], j. DELTA v + v[1] );

  The only absolute numeric requirements are that if i=n, then the value
  computed from i . DELTA u + u[1] is exactly u[2], and if j=m, then the
  value computed from i . DELTA v + v[1] is exactly v[2].

ASSOCIATED GETS
       glGet() with argument GL_MAP1_GRID_DOMAIN
       glGet() with argument GL_MAP2_GRID_DOMAIN
       glGet() with argument GL_MAP1_GRID_SEGMENTS
       glGet() with argument GL_MAP2_GRID_SEGMENTS

SEE ALSO
  glEvalCoord(3), glEvalMesh(3), glMap1(3), glMap2(3), glMapGrid(3)

Index for Section 3G

Alphabetical listing for G

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