Sylpheed

/* GtkSHRuler

 *

 *  Copyright (C) 2000-2005 Alfons Hoogervorst & The Sylpheed Claws Team

 *

 * 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., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

/* I derived this class from hruler. S in HRuler could be read as

 * Sylpheed (sylpheed.good-day.net), but also [S]ettable HRuler.

 * I basically ripped apart the draw_ticks member of HRuler; it

 * now draws the ticks at ruler->max_size. so gtk_ruler_set_range's

 * last parameter has the distance between two ticks (which is

 * the width of the fixed font character!

 * 

 * -- Alfons

 */

#include <math.h>

#include <stdio.h>

#include <string.h>

#include <gtk/gtkhruler.h>

#include "gtkshruler.h"

#define RULER_HEIGHT          14

#define MINIMUM_INCR          5

#define MAXIMUM_SUBDIVIDE     5

#define MAXIMUM_SCALES        10

#define ROUND(x) ((int) ((x) + 0.5))

static void gtk_shruler_class_init           (GtkSHRulerClass *klass);

static void gtk_shruler_init                 (GtkSHRuler      *hruler);

static void gtk_shruler_draw_ticks         (GtkRuler        *ruler);

#if 0

static void gtk_shruler_draw_pos              (GtkRuler        *ruler);

#endif

GType

gtk_shruler_get_type(void)

{

        static GType shruler_type = 0;

          if ( !shruler_type ) {

                   static const GTypeInfo shruler_info = {

                        sizeof (GtkSHRulerClass),

                        (GBaseInitFunc) NULL,

                        (GBaseFinalizeFunc) NULL,

                        (GClassInitFunc) gtk_shruler_class_init,

                        (GClassFinalizeFunc) NULL,

                        NULL,        /* class_data */

                        sizeof (GtkSHRuler),

                        0,        /* n_preallocs */

                        (GInstanceInitFunc) gtk_shruler_init,

                };

                /* inherit from GtkHRuler */

                shruler_type = g_type_register_static (GTK_TYPE_HRULER, "GtkSHRuler", &shruler_info, (GTypeFlags)0);

        }

        return shruler_type;

}

static void

gtk_shruler_class_init(GtkSHRulerClass * klass)

{

         GtkWidgetClass * widget_class;

          GtkRulerClass * hruler_class;

          widget_class = (GtkWidgetClass*) klass;

          hruler_class = (GtkRulerClass*) klass;

        /* just neglect motion notify events */

          widget_class->motion_notify_event = NULL /* gtk_shruler_motion_notify */;

          /* we want the old ruler draw ticks... */

          /* ruler_class->draw_ticks = gtk_hruler_draw_ticks; */

        hruler_class->draw_ticks = gtk_shruler_draw_ticks;

        /* unimplemented draw pos */

        hruler_class->draw_pos = NULL;

/*

          hruler_class->draw_pos = gtk_shruler_draw_pos;

*/

}

static void

gtk_shruler_init (GtkSHRuler * shruler)

{

        GtkWidget * widget;

        widget = GTK_WIDGET (shruler);

        widget->requisition.width = widget->style->xthickness * 2 + 1;

        widget->requisition.height = widget->style->ythickness * 2 + RULER_HEIGHT;

}

GtkWidget*

gtk_shruler_new(void)

{

        return GTK_WIDGET( g_object_new( gtk_shruler_get_type(), NULL ) );

}

static void

gtk_shruler_draw_ticks(GtkRuler *ruler)

{

        GtkWidget *widget;

        GdkGC *gc, *bg_gc;

        gint i;

        gint width, height;

        gint xthickness;

        gint ythickness;

        gint pos;

        g_return_if_fail (ruler != NULL);

        g_return_if_fail (GTK_IS_HRULER (ruler));

        if (!GTK_WIDGET_DRAWABLE (ruler)) 

                return;

        widget = GTK_WIDGET (ruler);

        gc = widget->style->fg_gc[GTK_STATE_NORMAL];

        bg_gc = widget->style->bg_gc[GTK_STATE_NORMAL];

        xthickness = widget->style->xthickness;

        ythickness = widget->style->ythickness;

        width = widget->allocation.width;

        height = widget->allocation.height - ythickness * 2;

        gtk_paint_box (widget->style, ruler->backing_store,

                       GTK_STATE_NORMAL, GTK_SHADOW_OUT, 

                       NULL, widget, "hruler",

                       0, 0, 

                       widget->allocation.width, widget->allocation.height);

#if 0

        gdk_draw_line (ruler->backing_store, gc,

                       xthickness,

                       height + ythickness,

                       widget->allocation.width - xthickness,

                       height + ythickness);

#endif

        /* assume ruler->max_size has the char width */

        /* i is increment of char_width,  pos is label number

         * y position is based on height of widget itself */

        for ( i = 0, pos = 0; i < widget->allocation.width - xthickness; i += ruler->max_size, pos++ ) {        

                gint length = height / 8;

                if ( pos % 10 == 0 ) length = ( 2 * height / 3 );

                else if ( pos % 5 == 0 ) length = ( height / 3 );

                gdk_draw_line(ruler->backing_store, gc,

                              i, height + ythickness,

                              i, height - length);                        

                if ( pos % 10 == 0 ) {

                        gchar buf[8];

                        PangoLayout *layout;

                        /* draw label */

                        g_snprintf(buf, sizeof buf, "%d", pos);

                        layout = gtk_widget_create_pango_layout

                                (GTK_WIDGET(ruler), buf);

                        gdk_draw_layout(ruler->backing_store, gc, i + 2,

                                        0, layout);

                        g_object_unref(layout);

                }

        }

}

/* gtk_ruler_set_pos() - does not work yet, need to reimplement 

 * gtk_ruler_draw_pos(). */

void

gtk_shruler_set_pos(GtkSHRuler * ruler, gfloat pos)

{

        GtkRuler * ruler_;

        g_return_if_fail( ruler != NULL );

        ruler_ = GTK_RULER(ruler);

        if ( pos < ruler_->lower ) 

                pos = ruler_->lower;

        if ( pos > ruler_->upper )

                pos = ruler_->upper;

        ruler_->position = pos;        

        /*  Make sure the ruler has been allocated already  */

        if ( ruler_->backing_store != NULL )

                gtk_ruler_draw_pos(ruler_);

}