.TH mapw2  3 "R1c" "Silicon Graphics"
.SH NAME
.I mapw2
- map a point on the screen into 2D world coordinates
.SH SYNOPSIS
.nf
.TP \w'FORTRAN\ \ \ 'u
C
.B "mapw2(vobj, sx, sy, wx, wy)"
.B "Object vobj;"
.B "Screencord sx, sy;"
.B "Coord *wx, *wy;"
.IP 
.TP \w'FORTRAN\ \ \ 'u
FORTRAN
.B "subroutine mapw2(vobj, sx, sy, wx, wy)"
.B "integer vobj"
.B "integer*2 sx, sy"
.B "real wx, wy"
.IP 
.TP \w'FORTRAN\ \ \ 'u
Pascal
.B "procedure mapw2(vobj: Object; sx, sy,: Screencoord; var wx, wy: Coord);"
.SH DESCRIPTION
.I Mapw2
is the two-dimensional version of \f2mapw\f1.  \f3Vobj\f1
is a viewing object containing the viewport, projection and 
viewing transformations
that define world space; \f3sx\f1 and \f3sy\f1 define 
a screen space point.
The corresponding world space coordinates are 
returned in \f3wx\f1 and \f3wy\f1.  If the transformation is not
2D, the result is undefined.
.SH "SEE ALSO"
.I mapw
.SH NOTE
This command can only be used in immediate mode.