src/zoom-context.cpp

   1 #define __SP_ZOOM_CONTEXT_C__
   2
   3 /*
   4  * Handy zooming tool
   5  *
   6  * Authors:
   7  *   Lauris Kaplinski <lauris@kaplinski.com>
   8  *   Frank Felfe <innerspace@iname.com>
   9  *   bulia byak <buliabyak@users.sf.net>
  10  *
  11  * Copyright (C) 1999-2002 Authors
  12  *
  13  * Released under GNU GPL, read the file 'COPYING' for more information
  14  */
  15
  16
  17 #include <gdk/gdkkeysyms.h>
  18
  19 #include "macros.h"
  20 #include "rubberband.h"
  21 #include "desktop.h"
  22 #include "pixmaps/cursor-zoom.xpm"
  23 #include "pixmaps/cursor-zoom-out.xpm"
  24 #include "prefs-utils.h"
  25
  26 #include "zoom-context.h"
  27
  28 static void sp_zoom_context_class_init(SPZoomContextClass *klass);
  29 static void sp_zoom_context_init(SPZoomContext *zoom_context);
  30 static void sp_zoom_context_setup(SPEventContext *ec);
  31 static void sp_zoom_context_finish (SPEventContext *ec);
  32
  33 static gint sp_zoom_context_root_handler(SPEventContext *event_context, GdkEvent *event);
  34 static gint sp_zoom_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event);
  35
  36 static SPEventContextClass *parent_class;
  37
  38 static gint xp = 0, yp = 0; // where drag started
  39 static gint tolerance = 0;
  40 static bool within_tolerance = false;
  41 static bool escaped;
  42
  43 GType sp_zoom_context_get_type(void)
  44 {
  45     static GType type = 0;
  46
  47     if (!type) {
  48         GTypeInfo info = {
  49             sizeof(SPZoomContextClass),
  50             NULL, NULL,
  51             (GClassInitFunc) sp_zoom_context_class_init,
  52             NULL, NULL,
  53             sizeof(SPZoomContext),
  54             4,
  55             (GInstanceInitFunc) sp_zoom_context_init,
  56             NULL,       /* value_table */
  57         };
  58         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPZoomContext", &info, (GTypeFlags) 0);
  59     }
  60
  61     return type;
  62 }
  63
  64 static void sp_zoom_context_class_init(SPZoomContextClass *klass)
  65 {
  66     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
  67
  68     parent_class = (SPEventContextClass*) g_type_class_peek_parent(klass);
  69
  70     event_context_class->setup = sp_zoom_context_setup;
  71     event_context_class->finish = sp_zoom_context_finish;
  72
  73     event_context_class->root_handler = sp_zoom_context_root_handler;
  74     event_context_class->item_handler = sp_zoom_context_item_handler;
  75 }
  76
  77 static void sp_zoom_context_init (SPZoomContext *zoom_context)
  78 {
  79     SPEventContext *event_context = SP_EVENT_CONTEXT(zoom_context);
  80
  81     event_context->cursor_shape = cursor_zoom_xpm;
  82     event_context->hot_x = 6;
  83     event_context->hot_y = 6;
  84 }
  85
  86 static void
  87 sp_zoom_context_finish (SPEventContext *ec)
  88 {
  89         ec->enableGrDrag(false);
  90 }
  91
  92 static void sp_zoom_context_setup(SPEventContext *ec)
  93 {
  94     if (prefs_get_int_attribute("tools.zoom", "selcue", 0) != 0) {
  95         ec->enableSelectionCue();
  96     }
  97     if (prefs_get_int_attribute("tools.zoom", "gradientdrag", 0) != 0) {
  98         ec->enableGrDrag();
  99     }
 100
 101     if (((SPEventContextClass *) parent_class)->setup) {
 102         ((SPEventContextClass *) parent_class)->setup(ec);
 103     }
 104 }
 105
 106 static gint sp_zoom_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event)
 107 {
 108     gint ret = FALSE;
 109
 110     if (((SPEventContextClass *) parent_class)->item_handler) {
 111         ret = ((SPEventContextClass *) parent_class)->item_handler (event_context, item, event);
 112     }
 113
 114     return ret;
 115 }
 116
 117 static gint sp_zoom_context_root_handler(SPEventContext *event_context, GdkEvent *event)
 118 {
 119     SPDesktop *desktop = event_context->desktop;
 120     tolerance = prefs_get_int_attribute_limited ("options.dragtolerance", "value", 0, 0, 100);
 121     double const zoom_inc = prefs_get_double_attribute_limited("options.zoomincrement", "value", M_SQRT2, 1.01, 10);
 122
 123     gint ret = FALSE;
 124
 125     switch (event->type) {
 126         case GDK_BUTTON_PRESS:
 127             if (event->button.button == 1) {
 128                 // save drag origin
 129                 xp = (gint) event->button.x;
 130                 yp = (gint) event->button.y;
 131                 within_tolerance = true;
 132
 133                 NR::Point const button_w(event->button.x, event->button.y);
 134                 NR::Point const button_dt(desktop->w2d(button_w));
 135                 Inkscape::Rubberband::get()->start(desktop, button_dt);
 136
 137                 escaped = false;
 138
 139                 ret = TRUE;
 140             }
 141             break;
 142
 143         case GDK_MOTION_NOTIFY:
 144             if (event->motion.state & GDK_BUTTON1_MASK) {
 145                 ret = TRUE;
 146
 147                 if ( within_tolerance
 148                      && ( abs( (gint) event->motion.x - xp ) < tolerance )
 149                      && ( abs( (gint) event->motion.y - yp ) < tolerance ) ) {
 150                     break; // do not drag if we're within tolerance from origin
 151                 }
 152                 // Once the user has moved farther than tolerance from the original location
 153                 // (indicating they intend to move the object, not click), then always process the
 154                 // motion notify coordinates as given (no snapping back to origin)
 155                 within_tolerance = false;
 156
 157                 NR::Point const motion_w(event->motion.x, event->motion.y);
 158                 NR::Point const motion_dt(desktop->w2d(motion_w));
 159                 Inkscape::Rubberband::get()->move(motion_dt);
 160             }
 161             break;
 162
 163         case GDK_BUTTON_RELEASE:
 164             if ( event->button.button == 1 ) {
 165                 NR::Maybe<NR::Rect> const b = Inkscape::Rubberband::get()->getRectangle();
 166                 if (b != NR::Nothing() && !within_tolerance) {
 167                     desktop->set_display_area(b.assume(), 10);
 168                 } else if (!escaped) {
 169                     NR::Point const button_w(event->button.x, event->button.y);
 170                     NR::Point const button_dt(desktop->w2d(button_w));
 171                     double const zoom_rel( (event->button.state & GDK_SHIFT_MASK)
 172                                            ? 1 / zoom_inc
 173                                            : zoom_inc );
 174                     desktop->zoom_relative_keep_point(button_dt, zoom_rel);
 175                 }
 176                 ret = TRUE;
 177             }
 178             Inkscape::Rubberband::get()->stop();
 179             xp = yp = 0;
 180             escaped = false;
 181             break;
 182
 183         case GDK_KEY_PRESS:
 184             switch (get_group0_keyval (&event->key)) {
 185                 case GDK_Escape:
 186                     Inkscape::Rubberband::get()->stop();
 187                     xp = yp = 0;
 188                     escaped = true;
 189                     ret = TRUE;
 190                     break;
 191                 case GDK_Up:
 192                 case GDK_Down:
 193                 case GDK_KP_Up:
 194                 case GDK_KP_Down:
 195                     // prevent the zoom field from activation
 196                     if (!MOD__CTRL_ONLY)
 197                         ret = TRUE;
 198                     break;
 199                 case GDK_Shift_L:
 200                 case GDK_Shift_R:
 201                     event_context->cursor_shape = cursor_zoom_out_xpm;
 202                     sp_event_context_update_cursor(event_context);
 203                     break;
 204                 default:
 205                         break;
 206                 }
 207                 break;
 208         case GDK_KEY_RELEASE:
 209             switch (get_group0_keyval (&event->key)) {
 210                 case GDK_Shift_L:
 211                 case GDK_Shift_R:
 212                     event_context->cursor_shape = cursor_zoom_xpm;
 213                     sp_event_context_update_cursor(event_context);
 214                     break;
 215                 default:
 216                     break;
 217                 }
 218             break;
 219         default:
 220             break;
 221     }
 222
 223     if (!ret) {
 224         if (((SPEventContextClass *) parent_class)->root_handler) {
 225             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
 226         }
 227     }
 228
 229     return ret;
 230 }
 231
 232 /*
 233   Local Variables:
 234   mode:c++
 235   c-file-style:"stroustrup"
 236   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 237   indent-tabs-mode:nil
 238   fill-column:99
 239   End:
 240 */
 241 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :