-- File:    Select3D_Projector.cdl
-- Created:    Thu Mar 12 13:32:28 1992
-- Author:    Christophe MARION
--        <cma@sdsun2> copie quasi exacte de HLRAlgo_Projector
---Copyright:     Matra Datavision 1992

class Projector from Select3D inherits Transient from Standard
    ---Purpose: A framework to define 3D projectors.
uses
    Real    from Standard,
    Boolean from Standard,
    Trsf    from gp,
    GTrsf   from gp,
    Lin     from gp,
    Pnt     from gp,
    Vec     from gp,
    Ax2     from gp,
    Vec2d   from gp,
    Pnt2d   from gp,
    Box     from Bnd,
    View    from V3d

raises
    NoSuchObject from Standard

is

    Create(aView:View from V3d) returns Projector from Select3D;
    --- Purpose: Constructs the 3D projector object defined by the 3D view aView.
    Create returns Projector from Select3D;

    Create(CS : Ax2 from gp)
    ---Purpose: Creates   an axonometric  projector.   <CS> is the
    --          viewing coordinate system.
    returns Projector from Select3D;

    Create(CS    : Ax2  from gp;
           Focus : Real from Standard)
    ---Purpose: Creates  a  perspective  projector.   <CS>  is the
    --          viewing coordinate system.
    returns Projector from Select3D;

    Create(T         : Trsf    from gp;
           Persp     : Boolean from Standard;
           Focus     : Real    from Standard)
    ---Purpose: build a Projector with automatic minmax directions.
    returns Projector from Select3D;

    Create(T         : Trsf    from gp;
           Persp     : Boolean from Standard;
           Focus     : Real    from Standard;
       v1,v2,v3  : Vec2d   from gp)
    ---Purpose: build a Projector with given minmax directions.
    returns Projector from Select3D;

    Create(GT        : GTrsf   from gp;
           Persp     : Boolean from Standard;
           Focus     : Real    from Standard)
    ---Purpose: build a Projector with automatic minmax directions.
    returns Projector from Select3D;

    Set (me : mutable;
         T         : Trsf    from gp;
         Persp     : Boolean from Standard;
         Focus     : Real    from Standard)
    is static;


    SetView(me : mutable; V : View from V3d);
    ---Purpose: Sets the 3D view V used at the time of construction.

    View(me) returns any View from V3d;
    ---Purpose: Returns the 3D view used at the time of construction.
    ---C++: return const&
    ---C++: inline


    Directions(me; D1 , D2 , D3 : out Vec2d from gp)
    ---C++: inline
    is virtual;

    Scaled(me : mutable; On : Boolean from Standard = Standard_False)
    ---Purpose: to compute with the given scale and translation.
    is virtual;

    Perspective(me) returns Boolean
    ---Purpose: Returns True if there is a perspective transformation.
    ---C++: inline
    is virtual;

    Transformation(me) returns GTrsf from gp
    ---Purpose: Returns the active transformation.
    ---C++: inline
    ---C++: return const &
    is virtual;

    InvertedTransformation(me) returns GTrsf from gp
    ---Purpose: Returns the active inverted transformation.
    ---C++: inline
    ---C++: return const &
    is virtual;

    FullTransformation(me) returns Trsf from gp
    ---Purpose: Returns the original transformation.
    ---C++: inline
    ---C++: return const &
    is virtual;

    Focus(me) returns Real from Standard
    ---Purpose: Returns the focal length.
    ---C++: inline
    raises
        NoSuchObject from Standard -- if there is no perspective
    is virtual;

    Transform(me; D : in out Vec from gp)
    ---C++: inline
    is virtual;

    Transform(me; Pnt : in out Pnt from gp)
        ---C++: inline
    is virtual;

    Project(me; P    :     Pnt   from gp;
                Pout : out Pnt2d from gp)
    ---Purpose: Transform and apply perspective if needed.
    is virtual;

    Project(me; P     :     Pnt  from gp;
                X,Y,Z : out Real from Standard)
    ---Purpose: Transform and apply perspective if needed.
    is static;

    Project(me; P     :     Pnt   from gp;
                D1    :     Vec   from gp;
                Pout  : out Pnt2d from gp;
        D1out : out Vec2d from gp)
    ---Purpose: Transform and apply perspective if needed.
    is virtual;

    BoxAdd(me; P :     Pnt2d from gp;
               B : out Box   from Bnd)
    ---Purpose: Adds to the box <B> the min-max of the point <P>.
    is virtual;

    Shoot(me; X , Y : Real from Standard)
    returns Lin from gp
    ---Purpose: return a line going through the eye towards the
    --          2d point <X,Y>.
    is virtual;

    DepthMin(me) returns Real from Standard;
    ---Purpose: Returns the minimum depth value (if clipping plane defined).
    ---         Should be used when call ::Shoot() to compute eyeline.
    ---C++: inline

    DepthMax(me) returns Real from Standard;
    ---Purpose: Returns the maximum depth value (if clipping plane defined).
    ---         Should be used when call ::Shoot() to compute eyeline.
    ---C++: inline

    DepthMinMax(me : mutable;
                theDepthMin : in Real from Standard;
                theDepthMax : in Real from Standard);
    ---Purpose: Setup the min/max depth values (doesn't affect
    ---         projection functionality itself).
    ---         Should be used when call ::Shoot() to compute eyeline.

    SetDirection(me : mutable)
    is static private;

    Transform(me; P : in out Pnt from gp;
                  T : GTrsf from gp)
    ---C++: inline
    is virtual;

    Transform(me; D : in out Lin from gp;
                  T : GTrsf from gp)
    ---C++: inline
    is virtual;

fields
    myType       : Integer from Standard;

    myPersp      : Boolean from Standard is protected;
    myFocus      : Real    from Standard is protected;
    myScaledTrsf : Trsf    from gp is protected;
    myGTrsf      : GTrsf   from gp is protected;
    myInvTrsf    : GTrsf   from gp is protected;
    myD1         : Vec2d   from gp is protected;
    myD2         : Vec2d   from gp is protected;
    myD3         : Vec2d   from gp is protected;

    myView       : View    from V3d;
    myDepthMin   : Real    from Standard;
    myDepthMax   : Real    from Standard;

end Projector;