Index for Section 3G

Alphabetical listing for G

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glMultMatrix(3G)
NAME
  glMultMatrix, glMultMatrixd, glMultMatrixf - multiply the current matrix
  with the specified matrix

SYNOPSIS
  void glMultMatrixd(
	  const GLdouble *m );

  void glMultMatrixf(
	  const GLfloat *m );

PARAMETERS
  m   Points to 16 consecutive values that are used as the elements of a 4
      times 4 column-major matrix.

DESCRIPTION
  glMultMatrix() multiplies the current matrix with the one specified using
  m, and replaces the current matrix with the product.

  The current matrix is determined by the current matrix mode (see
  glMatrixMode()). It is either the projection matrix, modelview matrix, or
  the texture matrix.

EXAMPLES
  If the current matrix is C, and the coordinates to be transformed are, v =
  (v[0], v[1], v[2], v[3]). Then the current transformation is C times v, or

       c[0]  c[4]  c[8]	 c[12]		 v[0]

       c[1]  c[5]  c[9]	 c[13]		 v[1]
				 times
       c[2]  c[6] c[10]	 c[14]		 v[2]

       c[3]  c[7] c[11]	 c[15]		 v[3]

  Calling glMultMatrix() with an argument of "m" = m[0], m[1], ..., m[15]
  replaces the current transformation with (C times M) times v, or

       c[0]  c[4]  c[8]	 c[12]		 m[0]  m[4]  m[8]  m[12]	  v[0]

       c[1]  c[5]  c[9]	 c[13]		 m[1]  m[5]  m[9]  m[13]	  v[1]
				 times				  times
       c[2]  c[6] c[10]	 c[14]		 m[2]  m[6] m[10]  m[14]	  v[2]

       c[3]  c[7] c[11]	 c[15]		 m[3]  m[7] m[11]  m[15]	  v[3]

  Where 'times' denotes matrix multiplication, and v is represented as a 4
  times 1 matrix.

NOTES
  While the elements of the matrix may be specified with single or double
  precision, the GL may store or operate on these values in less than single
  precision.

  In many computer languages 4 times 4 arrays are represented in row-major
  order. The transformations just described represent these matrices in
  column-major order. The order of the multiplication is important. For
  example, if the current transformation is a rotation, and glMultMatrix() is
  called with a translation matrix, the translation is done directly on the
  coordinates to be transformed, while the rotation is done on the results of
  that translation.

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

ASSOCIATED GETS
       glGet() with argument GL_MATRIX_MODE
       glGet() with argument GL_COLOR_MATRIX
       glGet() with argument GL_MODELVIEW_MATRIX
       glGet() with argument GL_PROJECTION_MATRIX
       glGet() with argument GL_TEXTURE_MATRIX

SEE ALSO
  glLoadIdentity(3), glLoadMatrix(3), glMatrixMode(3), glPushMatrix(3)

Index for Section 3G

Alphabetical listing for G

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