ARCED nged BRL-CAD BRL-CAD User Commands
arced Provides a means for directly editing transformation matrices of Boolean tree leaves.
`arced` comb/memb anim_command

## DESCRIPTION

The objects in a BRL-CAD model are stored as Boolean combinations of primitive shapes and/or other combinations. These combinations are stored as Boolean trees, with each leaf of the tree including a corresponding transformation matrix. The `arced` command provides a means for directly editing these matrices. The first argument to the `arced` command must identify the combination and which member's matrix is to be edited. The comb/memb argument indicates that member memb of combination comb has the matrix to be edited. The remainder of the `arced`command line consists of an animation command to be applied to that matrix. The available animation commands are:

`matrix rarc <xlate|rot> matrix elements`

  Replace the members matrix with the given matrix.

`matrix lmul <xlate|rot> matrix elements`

  Left multiply the members matrix with the given matrix.

`matrix rmul <xlate|rot> matrix elements`

  Right multiply the members matrix with the given matrix.

## EXAMPLES

Rotate body/head 45 degrees about Z axis

mged> `arced body/head matrix rot 0 0 45`

Rotates member head (in combination body) about the z axis through a 45° angle. By default, the `matrix` commands expect a list of 16 matrix elements to define a matrix. The xlate option may be used along with three translation distances in the x, y, and z directions (in mm) as a shorthand notation for a matrix that is pure translation. Similarly, the rot option along with rotation angles (degrees) about the x, y, and z axes may be used as shorthand for a matrix that is pure rotation.

## AUTHOR

BRL-CAD Team

## BUG REPORTS

Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org