Changes

=== Local Coordinate System ===

[[EM.Cube]] provides a number of different coordinate systems. The two most important ones are the World Coordinate System (WCS) and the Local Coordinate System (LCS). Every object has a Local Coordinate System that determines the location of the object in the world coordinate system and its orientation, i.e., its rotation angles with respect to the world principal axes. The center of the local coordinate system is the most important characteristic point of an object. The position of the LCS center varies among different object types. For example, the LCS center of a box is the center of its bottom face, while the LCS center of a sphere is its true geometrical center. The LCS has three local X-, Y-, and Z-axes. For most objects, these axes line up with the object's natural axes. For example, the local Z-axis of a cylinder or a cone is always aligned along its geometrical axis. When you draw a new object, its LCS axes are aligned along the principal world axes by default. After you rotate an object, its LCS axes are no longer aligned with the principal world axes.

When you start the [[EM.Cube]] application, you will only see the world X- and Y-axes in the Project Workspace. A small trident icon at the lower left corner of the workspace also shows the world coordinate system at all times. There are many instances when the relative orientation of objects with respect to one another and their positive or negative directions are very important. In such cases, making the LCS of objects visible would be very useful. You can enable the local coordinate system of an object by selecting it, right clicking on the surface of the object or right clicking on its name in the Navigation Tree and selecting '''Show LCS''' from the contextual menu. This will display the red, green and blue local X-, Y- and Z-axes of the objects in dashed lines. To disable the LCS, select '''Hide LCS''' from the contextual menu of that object.

=== General Drawing Rules ===