inkscape/src/sp-spiral.h

	sp-spiral.h revision 51dc158adbe2c9d1df3c941cbf78b90944d1afc2
#ifndef SEEN_SP_SPIRAL_H
#define SEEN_SP_SPIRAL_H
/*
 * Authors:
 *   Mitsuru Oka <oka326@parkcity.ne.jp>
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *
 * Copyright (C) 1999-2002 Lauris Kaplinski
 * Copyright (C) 2000-2001 Ximian, Inc.
 *
 * Released under GNU GPL, read the file 'COPYING' for more information
 */

#include "sp-shape.h"

#define noSPIRAL_VERBOSE

#define SP_EPSILON       1e-5
#define SP_EPSILON_2     (SP_EPSILON * SP_EPSILON)
#define SP_HUGE          1e5

#define SPIRAL_TOLERANCE 3.0
#define SAMPLE_STEP      (1.0/4.0) ///< step per 2PI
#define SAMPLE_SIZE      8         ///< sample size per one bezier

#define SP_TYPE_SPIRAL            (sp_spiral_get_type ())
#define SP_SPIRAL(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), SP_TYPE_SPIRAL, SPSpiral))
#define SP_SPIRAL_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), SP_TYPE_SPIRAL, SPSpiralClass))
#define SP_IS_SPIRAL(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), SP_TYPE_SPIRAL))
#define SP_IS_SPIRAL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), SP_TYPE_SPIRAL))

class CSpiral;
/**
 * A spiral Shape.
 *
 * The Spiral shape is defined as:
 * \verbatim
   x(t) = rad * t^exp cos(2 * Pi * revo*t + arg) + cx
   y(t) = rad * t^exp sin(2 * Pi * revo*t + arg) + cy    \endverbatim
 * where spiral curve is drawn for {t | t0 <= t <= 1}. The  rad and arg
 * parameters can also be represented by transformation.
 *
 * \todo Should I remove these attributes?
 */
class SPSpiral : public SPShape {
public:
    CSpiral* cspiral;

    float cx, cy;
    float exp;  ///< Spiral expansion factor
    float revo; ///< Spiral revolution factor
    float rad;  ///< Spiral radius
    float arg;  ///< Spiral argument
    float t0;
};

/// The SPSpiral vtable.
struct SPSpiralClass {
    SPShapeClass parent_class;
};


class CSpiral : public CShape {
public:
    CSpiral(SPSpiral* spiral);
    virtual ~CSpiral();

    virtual void build(SPDocument* doc, Inkscape::XML::Node* repr);
    virtual Inkscape::XML::Node* write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags);
    virtual void update(SPCtx *ctx, guint flags);
    virtual void set(unsigned int key, gchar const* value);

    virtual void snappoints(std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs);
    virtual gchar* description();

    virtual void set_shape();
    virtual void update_patheffect(bool write);

protected:
    SPSpiral* spspiral;
};


/* Standard Gtk function */
GType sp_spiral_get_type  (void);

/* Lowlevel interface */
void    sp_spiral_position_set      (SPSpiral      *spiral,
                 gdouble    cx,
                 gdouble    cy,
                 gdouble    exp,
                 gdouble    revo,
                 gdouble    rad,
                 gdouble    arg,
                 gdouble    t0);

Geom::Point    sp_spiral_get_xy (SPSpiral const *spiral,
                 gdouble    t);

void    sp_spiral_get_polar (SPSpiral const *spiral,
                 gdouble    t,
                 gdouble       *rad,
                 gdouble       *arg);

bool sp_spiral_is_invalid   (SPSpiral const *spiral);


#endif // SEEN_SP_SPIRAL_H