/* GTK - The GIMP Toolkit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#ifndef __GTK_CURVE_H__
#define __GTK_CURVE_H__


#include <gdk/gdk.h>
#include <gtk/gtkvbox.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */


#define GTK_CURVE(obj)        GTK_CHECK_CAST (obj, gtk_curve_get_type (), GtkCurve)
#define GTK_CURVE_CLASS(klass) GTK_CHECK_CLASS_CAST (klass, gtk_curve_get_type, GtkCurveClass)
#define GTK_IS_CURVE(obj)     GTK_CHECK_TYPE (obj, gtk_curve_get_type ())

typedef struct _GtkCurve	GtkCurve;
typedef struct _GtkCurveClass	GtkCurveClass;

typedef enum _GtkCurveType
  {
    GTK_CURVE_TYPE_LINEAR,	/* linear interpolation */
    GTK_CURVE_TYPE_SPLINE,	/* spline interpolation */
    GTK_CURVE_TYPE_FREE		/* free form curve */
  }
GtkCurveType;

struct _GtkCurve
  {
    GtkVBox vbox;
    GtkWidget *graph;		/* drawing-area */
    GtkWidget *linear_button;
    GtkWidget *spline_button;
    GtkWidget *free_button;

    gint cursor_type;
    gfloat min_x;
    gfloat max_x;
    gfloat min_y;
    gfloat max_y;
    GdkPixmap *pixmap;
    GtkCurveType curve_type;
    gint height;		/* (cached) graph height in pixels */
    gint grab_point;		/* point currently grabbed */
    gint last;

    /* (cached) curve points: */
    gint num_points;
    GdkPoint *point;

    /* control points: */
    gint num_ctlpoints;		/* number of control points */
    gfloat (*ctlpoint)[2];	/* array of control points */
  };

struct _GtkCurveClass
  {
    GtkVBoxClass parent_class;
  };


guint		gtk_curve_get_type	(void);
GtkWidget*	gtk_curve_new		(void);
void		gtk_curve_reset		(GtkCurve *curve);
void		gtk_curve_set_range	(GtkCurve *curve,
					 gfloat min_x, gfloat max_x,
					 gfloat min_y, gfloat max_y);
void		gtk_curve_get_vector	(GtkCurve *curve,
					 int veclen, gfloat vector[]);
void		gtk_curve_set_vector	(GtkCurve *curve,
					 int veclen, gfloat vector[]);

#ifdef __cplusplus
}
#endif /* __cplusplus */


#endif /* __GTK_CURVE_H__ */
