glMultMatrix

GLMULTMATRIX(3G)					     GLMULTMATRIX(3G)



NAME
       glMultMatrixd,  glMultMatrixf  -	 multiply the current matrix with the
       specified matrix


C SPECIFICATION
       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
	  4×4 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×v, or

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



















			    c[1] c[5] c[9]  c[13]   v[1]









			   (			 )×(	)









			    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×M)×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]









	       (		     )×(		     )×(    )









		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 ’×’ denotes matrix multiplication, and v is represented as a 4×1
       matrix.

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

       In  many	 computer  languages  4×4 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(3G),	  glLoadMatrix(3G),	    glMatrixMode(3G),
       glPushMatrix(3G)




							     GLMULTMATRIX(3G)