1 /* Dia -- an diagram creation/manipulation program
2 * Copyright (C) 1998 Alexander Larsson
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program 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
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 /*! \file connection.c -- This file handles simple (straight-line) connection basics */
20 #include <config.h>
21
22 #include <stdio.h>
23 #include <string.h> /* memcpy() */
24 #include <assert.h>
25
26 #include "connection.h"
27 #include "message.h"
28
29 /** Adjust connection endings for autogap. This function actually moves the
30 * ends of the connection, but only when the end is connected to
31 * a mainpoint.
32 */
33 void
connection_adjust_for_autogap(Connection * connection)34 connection_adjust_for_autogap(Connection *connection)
35 {
36 Point endpoints[2];
37 ConnectionPoint *start_cp, *end_cp;
38
39 start_cp = connection->endpoint_handles[0].connected_to;
40 end_cp = connection->endpoint_handles[1].connected_to;
41
42 endpoints[0] = connection->endpoints[0];
43 endpoints[1] = connection->endpoints[1];
44
45 if (connpoint_is_autogap(start_cp)) {
46 endpoints[0] = start_cp->pos;
47 }
48 if (connpoint_is_autogap(end_cp)) {
49 endpoints[1] = end_cp->pos;
50 }
51
52 if (connpoint_is_autogap(start_cp)) {
53 connection->endpoints[0] = calculate_object_edge(&endpoints[0],
54 &endpoints[1],
55 start_cp->object);
56 }
57 if (connpoint_is_autogap(end_cp)) {
58 connection->endpoints[1] = calculate_object_edge(&endpoints[1],
59 &endpoints[0],
60 end_cp->object);
61 }
62 }
63
64 /** Function called to move one of the handles associated with the
65 * object.
66 * This is an object_ops function.
67 * @param obj The object whose handle is being moved.
68 * @param handle The handle being moved.
69 * @param pos The position it has been moved to (corrected for
70 * vertical/horizontal only movement).
71 * @param cp If non-NULL, the connectionpoint found at this position.
72 * If @a cp is NULL, there may or may not be a connectionpoint.
73 * @param The reason the handle was moved.
74 * - HANDLE_MOVE_USER means the user is dragging the point.
75 * - HANDLE_MOVE_USER_FINAL means the user let go of the point.
76 * - HANDLE_MOVE_CONNECTED means it was moved because something
77 * it was connected to moved.
78 * @param modifiers gives a bitset of modifier keys currently held down
79 * - MODIFIER_SHIFT is either shift key
80 * - MODIFIER_ALT is either alt key
81 * - MODIFIER_CONTROL is either control key
82 * Each has MODIFIER_LEFT_* and MODIFIER_RIGHT_* variants
83 * @return An @a ObjectChange* with additional undo information, or
84 * (in most cases) NULL. Undo for moving the handle itself is handled
85 * elsewhere.
86 */
87 ObjectChange*
connection_move_handle(Connection * conn,HandleId id,Point * to,ConnectionPoint * cp,HandleMoveReason reason,ModifierKeys modifiers)88 connection_move_handle(Connection *conn, HandleId id,
89 Point *to, ConnectionPoint *cp,
90 HandleMoveReason reason, ModifierKeys modifiers)
91 {
92 switch(id) {
93 case HANDLE_MOVE_STARTPOINT:
94 conn->endpoints[0] = *to;
95 break;
96 case HANDLE_MOVE_ENDPOINT:
97 conn->endpoints[1] = *to;
98 break;
99 default:
100 message_error("Internal error in connection_move_handle.\n");
101 break;
102 }
103 return NULL;
104 }
105
106 /** Update the type and placement of the two handles.
107 * This only updates handles 0 and 1, not any handles added by subclasses.
108 * @param conn The connection object to do the update on.
109 */
110 void
connection_update_handles(Connection * conn)111 connection_update_handles(Connection *conn)
112 {
113 conn->endpoint_handles[0].id = HANDLE_MOVE_STARTPOINT;
114 conn->endpoint_handles[0].pos = conn->endpoints[0];
115
116 conn->endpoint_handles[1].id = HANDLE_MOVE_ENDPOINT;
117 conn->endpoint_handles[1].pos = conn->endpoints[1];
118 }
119
120 /** Update the bounding box for a connection.
121 * @param conn The connection to update bounding box on.
122 */
123 void
connection_update_boundingbox(Connection * conn)124 connection_update_boundingbox(Connection *conn)
125 {
126 assert(conn != NULL);
127
128 line_bbox(&conn->endpoints[0],&conn->endpoints[1],
129 &conn->extra_spacing,&conn->object.bounding_box);
130 }
131
132 /** Initialize a connection objects.
133 * This will in turn call object_init.
134 * @param conn A newly allocated connection object.
135 * @param num_handles How many handles to allocate room for.
136 * @param num_connections How many connectionpoints to allocate room for.
137 */
138 void
connection_init(Connection * conn,int num_handles,int num_connections)139 connection_init(Connection *conn, int num_handles, int num_connections)
140 {
141 DiaObject *obj;
142 int i;
143
144 obj = &conn->object;
145
146 assert(num_handles>=2);
147
148 object_init(obj, num_handles, num_connections);
149
150 assert(obj->handles!=NULL);
151
152 for (i=0;i<2;i++) {
153 obj->handles[i] = &conn->endpoint_handles[i];
154 obj->handles[i]->type = HANDLE_MAJOR_CONTROL;
155 obj->handles[i]->connect_type = HANDLE_CONNECTABLE;
156 obj->handles[i]->connected_to = NULL;
157 }
158 }
159
160 /** Copies an object connection-level and down.
161 * @param from The object to copy from.
162 * @param to The newly allocated object to copy into.
163 */
164 void
connection_copy(Connection * from,Connection * to)165 connection_copy(Connection *from, Connection *to)
166 {
167 int i;
168 DiaObject *toobj;
169 DiaObject *fromobj;
170
171 toobj = &to->object;
172 fromobj = &from->object;
173
174 object_copy(fromobj, toobj);
175
176 for (i=0;i<2;i++) {
177 to->endpoints[i] = from->endpoints[i];
178 }
179
180 for (i=0;i<2;i++) {
181 /* handles: */
182 to->endpoint_handles[i] = from->endpoint_handles[i];
183 to->endpoint_handles[i].connected_to = NULL;
184 toobj->handles[i] = &to->endpoint_handles[i];
185 }
186 memcpy(&to->extra_spacing,&from->extra_spacing,sizeof(to->extra_spacing));
187 }
188
189 /** Function called before an object is deleted.
190 * This function must call the parent class's DestroyFunc, and then free
191 * the memory associated with the object, but not the object itself
192 * Must also unconnect itself from all other objects, which can be done
193 * by calling object_destroy, or letting the super-class call it)
194 * This is one of the object_ops functions.
195 * @param conn An object to destroy.
196 */
197 void
connection_destroy(Connection * conn)198 connection_destroy(Connection *conn)
199 {
200 object_destroy(&conn->object);
201 }
202
203 /** Save a connections data to XML.
204 * @param conn The connection to save.
205 * @param obj_node The XML node to save it to.
206 */
207 void
connection_save(Connection * conn,ObjectNode obj_node)208 connection_save(Connection *conn, ObjectNode obj_node)
209 {
210 AttributeNode attr;
211
212 object_save(&conn->object, obj_node);
213
214 attr = new_attribute(obj_node, "conn_endpoints");
215 data_add_point(attr, &conn->endpoints[0]);
216 data_add_point(attr, &conn->endpoints[1]);
217 }
218
219 /** Load a connections data from XML.
220 * @param conn A fresh connection object to load into.
221 * @param obj_node The XML node to load from.
222 */
223 void
connection_load(Connection * conn,ObjectNode obj_node)224 connection_load(Connection *conn, ObjectNode obj_node)
225 {
226 AttributeNode attr;
227 DataNode data;
228
229 object_load(&conn->object, obj_node);
230
231 attr = object_find_attribute(obj_node, "conn_endpoints");
232 if (attr != NULL) {
233 data = attribute_first_data(attr);
234 data_point( data , &conn->endpoints[0] );
235 data = data_next(data);
236 data_point( data , &conn->endpoints[1] );
237 }
238 }
239