mat4x3pnt matrix "x y z"MAT4X3PNT(nged)
NAME
mat4x3pnt - transform a 3D point by a 4x4 matrix
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SYNOPSIS
DESCRIPTION
The mat4x3pnt command applies a 4x4 homogeneous transformation matrix to a 3D point, returning the resulting transformed point. It uses the MAT4X3PNT macro, which performs the full 4x4 matrix multiplication but discards the homogeneous w component, yielding a 3D Cartesian output point.
Arguments:
-
matrix : A 4x4 transformation matrix provided as a 16-element space-separated string (as produced by
bn_encode_mator commands likemat_ae,mat_mul). -
"x y z" : The 3D point to transform, provided as a space-separated string decoded by
bn_decode_vect.
The result is returned as a space-separated 3-element vector string.
EXAMPLES
Example 1. Transform the origin by an identity matrix
mged> mat4x3pnt "1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1" "10 20 30"
10 20 30
The identity matrix leaves the point unchanged.
Example 2. Apply a rotation matrix to a point
mged> set rot [mat_ae 90 0] mged> mat4x3pnt $rot "100 0 0"
Rotates the point (100, 0, 0) by 90° in azimuth, which places it on the Y axis.
AUTHOR
BRL-CAD Team
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org