1 /* GTK - The GIMP Toolkit
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
21 * Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GTK+ Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
28 #include <glib/gprintf.h>
30 #include "gtkhruler.h"
33 #define RULER_HEIGHT 14
34 #define MINIMUM_INCR 5
35 #define MAXIMUM_SUBDIVIDE 5
36 #define MAXIMUM_SCALES 10
38 #define ROUND(x) ((int) ((x) + 0.5))
41 static void gtk_hruler_class_init (GtkHRulerClass *klass);
42 static void gtk_hruler_init (GtkHRuler *hruler);
43 static gint gtk_hruler_motion_notify (GtkWidget *widget,
44 GdkEventMotion *event);
45 static void gtk_hruler_draw_ticks (GtkRuler *ruler);
46 static void gtk_hruler_draw_pos (GtkRuler *ruler);
50 gtk_hruler_get_type (void)
52 static GType hruler_type = 0;
56 static const GTypeInfo hruler_info =
58 sizeof (GtkHRulerClass),
60 NULL, /* base_finalize */
61 (GClassInitFunc) gtk_hruler_class_init,
62 NULL, /* class_finalize */
63 NULL, /* class_data */
66 (GInstanceInitFunc) gtk_hruler_init,
69 hruler_type = g_type_register_static (GTK_TYPE_RULER, "GtkHRuler",
77 gtk_hruler_class_init (GtkHRulerClass *klass)
79 GtkWidgetClass *widget_class;
80 GtkRulerClass *ruler_class;
82 widget_class = (GtkWidgetClass*) klass;
83 ruler_class = (GtkRulerClass*) klass;
85 widget_class->motion_notify_event = gtk_hruler_motion_notify;
87 ruler_class->draw_ticks = gtk_hruler_draw_ticks;
88 ruler_class->draw_pos = gtk_hruler_draw_pos;
92 gtk_hruler_init (GtkHRuler *hruler)
96 widget = GTK_WIDGET (hruler);
97 widget->requisition.width = widget->style->xthickness * 2 + 1;
98 widget->requisition.height = widget->style->ythickness * 2 + RULER_HEIGHT;
103 gtk_hruler_new (void)
105 return g_object_new (GTK_TYPE_HRULER, NULL);
109 gtk_hruler_motion_notify (GtkWidget *widget,
110 GdkEventMotion *event)
115 ruler = GTK_RULER (widget);
118 gdk_window_get_pointer (widget->window, &x, NULL, NULL);
122 ruler->position = ruler->lower + ((ruler->upper - ruler->lower) * x) / widget->allocation.width;
123 g_object_notify (G_OBJECT (ruler), "position");
125 /* Make sure the ruler has been allocated already */
126 if (ruler->backing_store != NULL)
127 gtk_ruler_draw_pos (ruler);
133 gtk_hruler_draw_ticks (GtkRuler *ruler)
141 gint length, ideal_length;
142 gdouble lower, upper; /* Upper and lower limits, in ruler units */
143 gdouble increment; /* Number of pixels per unit */
144 gint scale; /* Number of units per major unit */
146 gdouble start, end, cur;
153 PangoRectangle logical_rect, ink_rect;
155 if (!GTK_WIDGET_DRAWABLE (ruler))
158 widget = GTK_WIDGET (ruler);
160 gc = widget->style->fg_gc[GTK_STATE_NORMAL];
161 bg_gc = widget->style->bg_gc[GTK_STATE_NORMAL];
163 xthickness = widget->style->xthickness;
164 ythickness = widget->style->ythickness;
166 digit_height = PANGO_PIXELS (ink_rect.height) + 2;
167 digit_offset = ink_rect.y;
169 layout = gtk_widget_create_pango_layout (widget, "012456789");
170 pango_layout_get_extents (layout, &ink_rect, &logical_rect);
172 digit_height = PANGO_PIXELS (ink_rect.height) + 1;
173 digit_offset = ink_rect.y;
175 width = widget->allocation.width;
176 height = widget->allocation.height - ythickness * 2;
178 gtk_paint_box (widget->style, ruler->backing_store,
179 GTK_STATE_NORMAL, GTK_SHADOW_OUT,
180 NULL, widget, "hruler",
182 widget->allocation.width, widget->allocation.height);
185 gdk_draw_line (ruler->backing_store, gc,
188 widget->allocation.width - xthickness,
189 height + ythickness);
191 upper = ruler->upper / ruler->metric->pixels_per_unit;
192 lower = ruler->lower / ruler->metric->pixels_per_unit;
194 if ((upper - lower) == 0)
196 increment = (gdouble) width / (upper - lower);
198 /* determine the scale
199 * We calculate the text size as for the vruler instead of using
200 * text_width = gdk_string_width(font, unit_str), so that the result
201 * for the scale looks consistent with an accompanying vruler
203 scale = ceil (ruler->max_size / ruler->metric->pixels_per_unit);
204 g_snprintf (unit_str, sizeof (unit_str), "%d", scale);
205 text_width = strlen (unit_str) * digit_height + 1;
207 for (scale = 0; scale < MAXIMUM_SCALES; scale++)
208 if (ruler->metric->ruler_scale[scale] * fabs(increment) > 2 * text_width)
211 if (scale == MAXIMUM_SCALES)
212 scale = MAXIMUM_SCALES - 1;
214 /* drawing starts here */
216 for (i = MAXIMUM_SUBDIVIDE - 1; i >= 0; i--)
218 subd_incr = (gdouble) ruler->metric->ruler_scale[scale] /
219 (gdouble) ruler->metric->subdivide[i];
220 if (subd_incr * fabs(increment) <= MINIMUM_INCR)
223 /* Calculate the length of the tickmarks. Make sure that
224 * this length increases for each set of ticks
226 ideal_length = height / (i + 1) - 1;
227 if (ideal_length > ++length)
228 length = ideal_length;
232 start = floor (lower / subd_incr) * subd_incr;
233 end = ceil (upper / subd_incr) * subd_incr;
237 start = floor (upper / subd_incr) * subd_incr;
238 end = ceil (lower / subd_incr) * subd_incr;
242 for (cur = start; cur <= end; cur += subd_incr)
244 pos = ROUND ((cur - lower) * increment);
246 gdk_draw_line (ruler->backing_store, gc,
247 pos, height + ythickness,
248 pos, height - length + ythickness);
253 g_snprintf (unit_str, sizeof (unit_str), "%d", (int) cur);
255 pango_layout_set_text (layout, unit_str, -1);
256 pango_layout_get_extents (layout, &logical_rect, NULL);
258 gtk_paint_layout (widget->style,
259 ruler->backing_store,
260 GTK_WIDGET_STATE (widget),
265 pos + 2, ythickness + PANGO_PIXELS (logical_rect.y - digit_offset),
271 g_object_unref (layout);
275 gtk_hruler_draw_pos (GtkRuler *ruler)
282 gint bs_width, bs_height;
287 if (GTK_WIDGET_DRAWABLE (ruler))
289 widget = GTK_WIDGET (ruler);
291 gc = widget->style->fg_gc[GTK_STATE_NORMAL];
292 xthickness = widget->style->xthickness;
293 ythickness = widget->style->ythickness;
294 width = widget->allocation.width;
295 height = widget->allocation.height - ythickness * 2;
297 bs_width = height / 2;
298 bs_width |= 1; /* make sure it's odd */
299 bs_height = bs_width / 2 + 1;
301 if ((bs_width > 0) && (bs_height > 0))
303 /* If a backing store exists, restore the ruler */
304 if (ruler->backing_store && ruler->non_gr_exp_gc)
305 gdk_draw_drawable (ruler->widget.window,
306 ruler->non_gr_exp_gc,
307 ruler->backing_store,
308 ruler->xsrc, ruler->ysrc,
309 ruler->xsrc, ruler->ysrc,
310 bs_width, bs_height);
312 increment = (gdouble) width / (ruler->upper - ruler->lower);
314 x = ROUND ((ruler->position - ruler->lower) * increment) + (xthickness - bs_width) / 2 - 1;
315 y = (height + bs_height) / 2 + ythickness;
317 for (i = 0; i < bs_height; i++)
318 gdk_draw_line (widget->window, gc,
320 x + bs_width - 1 - i, y + i);