AcDbEntity::getEcs

C++

virtual ACDBCORE2D_PORT void getEcs(
    AcGeMatrix3d& retVal
) const;

Description

This function is intended to be overridden by derived classes that need to be able to provide access to an object coordinate system for objects of the class. The intent is that this function provide a transformation matrix that can be used to transform vectors or points from the object's object coordinate system (OCS) to the World Coordinate System (WCS).

Default implementation: Return the identity matrix (ones along the diagonal, zeros elsewhere) in retVal.

We recommend that all data stored in custom classes be stored in WCS coordinates. If this is done, then the object's OCS will be the WCS and the transformation matrix will be the identity matrix. Then this function will not need to be overridden since the identity matrix is this function's default return.

Note Even the pre-R13 entity types that store their data in OCS format (that is, circle, polyline, inserts, etc.) return the identity matrix.

Parameters

Links

AcDbEntity