# SUBSYSTEM OVERVIEW

IGES Math (IMTH) Subsystem

The IMTH subsystem performs math operations specific to IGES data types. These data types include the transformation matrix (IMTH_MATRIX). Use the IMTH_NOOPT option for any unused option masks.

# MATRIX FUNCTIONSS

IGES matrices are defined by a typedef called IMTH_MATRIX. The typedef consists of a 3 by 4 array of doubles corresponding to the 3 by 4 matrix defined for the IGES Transformation Matrix entity. The following functions perform matrix operations:

imth_ApplyMatrix3D Applies a matrix to 3D point(s) imth_ApplyMatrix4D Applies a matrix to 3D point(s) imth_ApplyEntityMatrix3D Applies an IGES entity matrix to 3D points imth_ApplyEntityMatrix4D Applies an IGES entity matrix to 4D points imth_CompareMatrix Compares two matrices for equality imth_ConcatEntityMatrix Concatenates IGES entities matrices imth_ConcatMatrix Concatenates 124 entity matrices imth_ConcatMatrix2 Concatenates two matrices imth_GetIdentMatrix Returns the loc. of an identity matrix imth_GetXYZMatrixAngles Extracts XYZ rotation angles imth_MakeIdentMatrix Creates an identity matrix imth_TestIdentMatrix Checks for an identity matrix imth_RemoveXYZMatrixScale Remove scale from matrix imth_SetMatrixFromAxisAngle Create a matrix from a rotation about an arbitrary axis imth_SetXYZMatrixFromAngles Create an XYZ rotation angle matrix imth_SetZYXMatrixFromAngles Create an ZYX rotation angle matrix

See the manual pages for the full bindings.