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doc/gl-docs/GL/gl/loadmatrix.3gl

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+'\" e
+'\"! eqn | mmdoc
+'\"macro stdmacro
+.ds Vn Version 1.2
+.ds Dt 24 September 1999
+.ds Re Release 1.2.1
+.ds Dp Jan 14 18:30
+.ds Dm 01 loadmatri
+.ds Xs 32571 5 loadmatrix.gl
+.TH GLLOADMATRIX 3G
+.SH NAME
+.B "glLoadMatrixd, glLoadMatrixf
+\- replace the current matrix with the specified matrix
+
+.SH C SPECIFICATION
+void \f3glLoadMatrixd\fP(
+const GLdouble \fI*m\fP )
+.nf
+.fi
+void \f3glLoadMatrixf\fP(
+const GLfloat \fI*m\fP )
+.nf
+.fi
+
+.EQ
+delim $$
+.EN
+.SH PARAMETERS
+.TP \w'\f2m\fP\ \ 'u 
+\f2m\fP
+Specifies a pointer to 16 consecutive values, which are used as the
+elements of a $4 ~times~ 4$ column-major matrix. 
+.SH DESCRIPTION
+\%\f3glLoadMatrix\fP replaces the current matrix with the one whose elements are specified by
+\f2m\fP.
+The current matrix is the projection matrix,
+modelview matrix,
+or texture matrix,
+depending on the current matrix mode
+(see \%\f3glMatrixMode\fP).
+.P
+The current matrix, M, defines a transformation of coordinates.
+For instance, assume M refers to the modelview matrix.
+If  $v ~=~ (v[0], v[1], v[2], v[3])$ is the set of object coordinates
+of a vertex,
+and \f2m\fP points to an array of $16$ 
+single- or double-precision
+floating-point values $m[0], m[1],. . .,m[15]$,
+then the modelview transformation $M(v)$ does the following:
+.P
+
+.ce
+.EQ
+down 130
+{M(v)  ~ = ~ 
+{{ left (  matrix {
+   ccol { ~m[0] above m[1] above m[2] above m[3] ~}
+   ccol { ~m[4] above m[5] above m[6] above m[7] ~}
+   ccol { ~m[8] above m[9] above m[10] above m[11] ~}
+   ccol { ~m[12]~ above m[13]~ above m[14]~ above m[15]~}
+} right ) } ~~ times ~~
+{left ( matrix {
+ccol { ~v[0]~ above ~v[1]~ above ~v[2]~ above ~v[3]~ }
+} right )} }}
+.EN
+
+.sp
+.P
+Where ``$times$'' denotes matrix multiplication.
+.P
+Projection and texture transformations are similarly defined.
+.SH NOTES
+While the elements of the matrix may be specified with
+single or double precision, the GL implementation may
+store or operate on these values in less than single
+precision.
+.SH ERRORS
+\%\f3GL_INVALID_OPERATION\fP is generated if \%\f3glLoadMatrix\fP
+is executed between the execution of \%\f3glBegin\fP
+and the corresponding execution of \%\f3glEnd\fP.
+.SH ASSOCIATED GETS
+\%\f3glGet\fP with argument \%\f3GL_MATRIX_MODE\fP
+.br
+\%\f3glGet\fP with argument \%\f3GL_COLOR_MATRIX\fP
+.br
+\%\f3glGet\fP with argument \%\f3GL_MODELVIEW_MATRIX\fP
+.br
+\%\f3glGet\fP with argument \%\f3GL_PROJECTION_MATRIX\fP
+.br
+\%\f3glGet\fP with argument \%\f3GL_TEXTURE_MATRIX\fP
+.SH SEE ALSO
+\%\f3glLoadIdentity(3G)\fP,
+\%\f3glMatrixMode(3G)\fP,
+\%\f3glMultMatrix(3G)\fP,
+\%\f3glPushMatrix(3G)\fP