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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 x 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 pro-jection projection
       jection 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 X 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]  X  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  transforma-tion transformation
       tion with (C X M) x 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] X m[2]  m[6]  m[10] m[14] X v[2]
        c[3]  c[7]  c[11] c[15]   m[3]  m[7]  m[11] m[15]   v[3]



       Where 'X' denotes matrix multiplication, and v is represented as a 4 X 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 X 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 impor-tant. important.
       tant. 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)

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