**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 4x4 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 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 transformation
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 4x4 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_MODELVIEW_MATRIX**
**glGet** with argument **GL_PROJECTION_MATRIX**
**glGet** with argument **GL_TEXTURE_MATRIX**
**SEE** **ALSO**
**glLoadIdentity**, **glLoadMatrix**, **glMatrixMode**, **glPushMatrix**