Module arrow
OpenGL arrows.
  The arrow module allows creation and drawing of arrows.  Clients draw 
  using graphics3d.common.Group instances, aliased here as ArrowGroup, not 
  through Arrow instances.
  Drawing is done in whatever is the current GL rendering context and 
  current GL window. So you must set those prior to drawing.  If you are 
  using this with Maestro's drawing callback mechanism you need not worry 
  about the above details.  These are handled for you automatically.
  Control over the endpoints, radius, color, resolution and transparency
  of a arrow are provided.  See the Arrow class for more info.
  To draw any number of arrows create Arrow instances, add them to a 
  Group instance, then invoke the Group's draw() method.
  Copyright Schrodinger LLC, All rights reserved.
    |  | ArrowCore Base class for drawing a 3D arrow
 | 
    |  | Arrow Class for drawing a 3D arrow in OpenGL.
 | 
    |  | MaestroArrow Class for creating a 3D arrow in Maestro
 | 
    |  |  | 
    |  | 
        
          | vector_cross(X,
        Y) Returns the cross product of the len 3 vectors X and Y
 |  |  | 
    |  | version = '$Revision: 1.13 $' | 
    |  | RESOLUTION_MIN = 4 | 
    |  | RESOLUTION_MAX = 50 | 
    |  | RESOLUTION_DEFAULT = 16 | 
    |  | _slices = 12 | 
    |  | _stacks = 1 | 
    |  | maestro = Nonehash(x)
 | 
    |  | TRANSPARENCY_DEFAULT = 0.0 | 
    |  | OPACITY_DEFAULT = 1.0 | 
    |  | BOUNDING_BOX_INIT_VALUE = 100000000.0 | 
    |  | EPSILON = 0.0001 | 
    |  | BODY_PERCENTAGE = 0.75 | 
    |  | __package__ = 'schrodinger.graphics3d' |