Method and apparatus for providing three-dimensional model associativity

A computer readable medium encoded with a program that, when executed on a computer aided design (CAD) system having a cursor that is controlled by a user to manipulate elements of a two-dimensional geometry in a two-dimensional sketch plane, the elements being concurrently displayed with elements of a three-dimensional geometry displayed in a two-dimensional display plane, performs a method for interpreting a position of the cursor, comprising the steps of:

• (A) positioning an element of the two-dimensional geometry in response to a first position of the cursor, wherein the two-dimensional geometry is sketched by a user in the two-dimensional sketch plane, and wherein the two-dimensional sketch plane is not parallel to the two-dimensional display plane;
• and
• (B) in response to the cursor being moved to a second position to reposition the element, providing, to the user, an indication of alignment of an element of the three-dimensional geometry with the cursor.

A CAD/CAM interface system comprising:

• a display interface having an output that provides to a display, having a two-dimensional display plane, a representation of a three-dimensional geometry, a representation of an object sketched by a user in a two-dimensional sketch plane that is not parallel to the two-dimensional display plane, and a representation of a cursor on the display;
• and
• means, responsive to a user selecting the object and moving the cursor, for translating movement of the cursor in the display plane into movement of the object in the two-dimensional sketch plane.

In a CAD/CAM system having a cursor that is controlled by a user to manipulate elements of a two-dimensional geometry in a two-dimensional sketch plane, the elements being concurrently displayed with elements of a three-dimensional geometry displayed in a two-dimensional display plane, an apparatus for interpreting a position of the cursor, the apparatus comprising:

• means for positioning an element of the two-dimensional geometry in response to a first position of the cursor, wherein the two-dimensional geometry is sketched by a user in the two-dimensional sketch plane, and wherein the two-dimensional sketch plane is not parallel to the two-dimensional display plane;
• and
• means for providing, to a user, an indication of alignment of an element of the three-dimensional geometry with the cursor, in response to the cursor being moved to a second position to reposition the element.