2010-07-31 [holger] 3.7.6cvs26
[claws.git] / src / gtk / gtkshruler.c
1 /* GtkSHRuler
2  *
3  *  Copyright (C) 2000-2005 Alfons Hoogervorst & The Claws Mail Team
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Library General Public
7  * License as published by the Free Software Foundation; either
8  * version 3 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Library General Public License for more details.
14  *
15  * You should have received a copy of the GNU Library General Public
16  * License along with this library. If not, see <http://www.gnu.org/licenses/>.
17  */
18  
19 /* I derived this class from hruler. S in HRuler could be read as
20  * Sylpheed (sylpheed.good-day.net), but also [S]ettable HRuler.
21  * I basically ripped apart the draw_ticks member of HRuler; it
22  * now draws the ticks at ruler->max_size. so gtk_ruler_set_range's
23  * last parameter has the distance between two ticks (which is
24  * the width of the fixed font character!
25  * 
26  * -- Alfons
27  */
28
29 #include <math.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <gtk/gtk.h>
33 #include "gtkshruler.h"
34 #include "utils.h"
35 #include "gtkutils.h"
36
37 #define RULER_HEIGHT          14
38 #define MINIMUM_INCR          5
39 #define MAXIMUM_SUBDIVIDE     5
40 #define MAXIMUM_SCALES        10
41
42 #define ROUND(x) ((int) ((x) + 0.5))
43
44 static void gtk_shruler_class_init      (GtkSHRulerClass *klass);
45 static void gtk_shruler_init            (GtkSHRuler      *hruler);
46 static void gtk_shruler_draw_ticks      (GtkRuler        *ruler);
47
48 GType
49 gtk_shruler_get_type(void)
50 {
51         static GType shruler_type = 0;
52
53         if ( !shruler_type ) {
54                 static const GTypeInfo shruler_info = {
55                         sizeof (GtkSHRulerClass),
56
57                         (GBaseInitFunc) NULL,
58                         (GBaseFinalizeFunc) NULL,
59
60                         (GClassInitFunc) gtk_shruler_class_init,
61                         (GClassFinalizeFunc) NULL,
62                         NULL,   /* class_data */
63
64                         sizeof (GtkSHRuler),
65                         0,      /* n_preallocs */
66                         (GInstanceInitFunc) gtk_shruler_init,
67                 };
68                 /* inherit from GtkHRuler */
69                 shruler_type = g_type_register_static (GTK_TYPE_HRULER, "GtkSHRuler", &shruler_info, (GTypeFlags)0);
70         }
71         return shruler_type;
72 }
73
74 static void
75 gtk_shruler_class_init(GtkSHRulerClass * klass)
76 {
77         GtkWidgetClass * widget_class;
78         GtkRulerClass * hruler_class;
79
80         widget_class = GTK_WIDGET_CLASS(klass);
81         hruler_class = GTK_RULER_CLASS(klass);
82
83         /* just neglect motion notify events */
84         widget_class->motion_notify_event = NULL /* gtk_shruler_motion_notify */;
85
86         /* we want the old ruler draw ticks... */
87         /* ruler_class->draw_ticks = gtk_hruler_draw_ticks; */
88         hruler_class->draw_ticks = gtk_shruler_draw_ticks;
89         
90         /* unimplemented draw pos */
91         hruler_class->draw_pos = NULL;
92 /*
93         hruler_class->draw_pos = gtk_shruler_draw_pos;
94 */
95 }
96
97 static void
98 gtk_shruler_init (GtkSHRuler * shruler)
99 {
100         GtkWidget * widget;
101         
102         widget = GTK_WIDGET (shruler);
103         widget->requisition.width = widget->style->xthickness * 2 + 1;
104         widget->requisition.height = widget->style->ythickness * 2 + RULER_HEIGHT;
105 }
106
107
108 GtkWidget*
109 gtk_shruler_new(void)
110 {
111         return GTK_WIDGET( g_object_new( gtk_shruler_get_type(), NULL ) );
112 }
113
114 static void
115 gtk_shruler_draw_ticks(GtkRuler *ruler)
116 {
117         GtkWidget *widget;
118         cairo_t *cr;
119         gint i;
120         gint width, height;
121         gint xthickness;
122         gint ythickness;
123         gint pos;
124
125         cm_return_if_fail (ruler != NULL);
126         cm_return_if_fail (GTK_IS_HRULER (ruler));
127
128         if (!gtkut_widget_is_drawable (GTK_WIDGET(ruler))) 
129                 return;
130
131         widget = GTK_WIDGET (ruler);
132         
133         cr = gdk_cairo_create(ruler->backing_store);
134         cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
135         cairo_set_line_width(cr, 1.);
136         gdk_cairo_set_source_color(cr, &gtk_widget_get_style(widget)->text[GTK_STATE_NORMAL]);
137
138         xthickness = widget->style->xthickness;
139         ythickness = widget->style->ythickness;
140
141         width = widget->allocation.width;
142         height = widget->allocation.height - ythickness * 2;
143   
144         gtk_paint_box (widget->style, ruler->backing_store,
145                        GTK_STATE_NORMAL, GTK_SHADOW_OUT, 
146                        NULL, widget, "hruler",
147                        0, 0, 
148                        widget->allocation.width, widget->allocation.height);
149
150         /* assume ruler->max_size has the char width */
151         /* i is increment of char_width,  pos is label number
152          * y position is based on height of widget itself */
153         for ( i = 0, pos = 0; i < widget->allocation.width - xthickness; i += ruler->max_size, pos++ ) {        
154                 gint length = height / 8;
155         
156                 if ( pos % 10 == 0 ) length = ( 2 * height / 3 );
157                 else if ( pos % 5 == 0 ) length = ( height / 3 );
158                 
159                 cairo_move_to(cr, i, height + ythickness);
160                 cairo_line_to(cr, i, height - length);
161                 cairo_stroke(cr);
162                 
163                 if ( pos % 10 == 0 ) {
164                         gchar buf[8];
165                         PangoLayout *layout;
166
167                         /* draw label */
168                         g_snprintf(buf, sizeof buf, "%d", pos);
169
170                         layout = gtk_widget_create_pango_layout
171                                 (GTK_WIDGET(ruler), buf);
172
173                         cairo_move_to(cr, i+2, 0);
174                         pango_cairo_show_layout(cr, layout);
175
176                         g_object_unref(layout);
177                 }
178         }
179
180         cairo_destroy(cr);
181 }