vpRotate(3) Library Functions Manual vpRotate(3) NAME vpRotate - multiply the current transformation matrix by a rotation matrix SYNOPSIS #include <volpack.h> vpResult vpRotate(vpc, axis, degrees) vpContext *vpc; int axis; double degrees; ARGUMENTS vpc VolPack context from vpCreateContext. axis Rotation axis code (VP_X_AXIS, VP_Y_AXIS or VP_Z_AXIS). degreesNumber of degrees to rotate. DESCRIPTION vpRotate is used to multiply the current transformation matrix by a 4-by-4 rotation matrix. The rotation axis must be one of the three principal viewing axes and is specified with one of the following codes: VP_X_AXIS X axis VP_Y_AXIS Y axis VP_Z_AXIS Z axis The rotation angle is specified in degrees. A positive angle indicates a clockwise rotation when looking towards the positive direction along the axis. For an X-axis rotation, the rotation matrix is: 1 0 0 0 0 cos(d) sin(d) 0 0 -sin(d) cos(d) 0 0 0 0 1 where d stands for the degrees argument. For a Y-axis rotation, the rota- tion matrix is: cos(d) 0 -sin(d) 0 0 1 0 0 sin(d) 0 cos(d) 0 0 0 0 1 For a Z-axis rotation, the rotation matrix is: cos(d) sin(d) 0 0 -sin(d) cos(d) 0 0 0 0 1 0 0 0 0 1 Use vpCurrentMatrix to set the current transformation matrix. By default, the rotation matrix is post-multiplied (M = M*R where M is the current ma- trix and R is the rotation matrix). The VP_CONCAT_MODE option to vpSeti can be used to select pre-multiplication. STATE VARIABLES The current matrix concatenation parameters can be retrieved with the fol- lowing state variable codes (see vpGeti(3)): VP_CURRENT_MATRIX, VP_CON- CAT_MODE. ERRORS The normal return value is VP_OK. The following error return value is pos- sible: VPERROR_BAD_OPTION The axis argument is invalid. SEE ALSO VolPack(3), vpCreateContext(3), vpCurrentMatrix(3) VolPack vpRotate(3)
NAME | SYNOPSIS | ARGUMENTS | DESCRIPTION | STATE VARIABLES | ERRORS | SEE ALSO
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=volpack-Rotate&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>