Abstract: A computer-aided illustration system and method emulate the set of tools that are typically available to the traditional technical illustrator and also provide the user with the ability to easily create illustrations in various two-dimensional projections, including paraline and perspective projections. The techniques described include: (1) providing moving polar grids which restrict a drawing to a user-specified geometry; (2) combining arbitrary user-specified directional constraints with several types of gravity, in a manner which enables a user to easily create new objects in alignment with previously drawn objects; (3) interrelating constraint systems and geometries (as delineated in the polar grids) with gravity, thereby providing the user with an effortless way to create objects with complex geometric interdependencies; and (4) adapting tools from linear geometry to work in non-linear projection planes (paraline and perspective).

Abstract: A computer-aided chemical illustration system is disclosed. Techniques provided include: 1) efficient drawing of bonds; 2) drawing different bond types during a single mode; 3) determining bisect angles for bonds; 4) labeling atoms on the fly; 5) automatic alignment of atom labels; 6) custom alignment of atom labels; 7) changing the type, style, or orientation of an object while it is being drawn; 8) detection of ring structures; and 9) shifting bonds around on a ring.

Abstract: A computer-aided chemical illustration system is disclosed. Techniques provided include: 1) efficient drawing of bonds; 2) drawing different bond types during a single mode; 3) determining bisect angles for bonds; 4) labeling atoms on the fly; 5) automatic alignment of atom labels; 6) custom alignment of atom labels; 7) changing the type, style, or orientation of an object while it is being drawn; 8) detection of ring structures; and 9) shifting bonds around on a ring.

Abstract: A computer-aided chemical illustration system is disclosed. Techniques provided include: 1) efficient drawing of bonds; 2) drawing different bond types during a single mode; 3) determining bisect angles for bonds; 4) labeling atoms on the fly; 5) automatic alignment of atom labels; 6) custom alignment of atom labels; 7) changing the type, style, or orientation of an object while it is being drawn; 8) detection of ring structures; and 9) shifting bonds around on a ring.