app/highlight.c

   1 /* Dia -- an diagram creation/manipulation program -*- c -*-
   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 #include "highlight.h"
  20
  21 #include "glib.h"
  22
  23 #include "diagram.h"
  24 #include "diagramdata.h"
  25 #include "object.h"
  26 #include "object_ops.h"
  27
  28 /* One could argue that the actual setting of the object's field
  29  * should happen inside lib rather than app.  I think that'd be overkill.
  30  * -Lars
  31  */
  32
  33 /* The highlighting must happen within a certain small area around the bbox.
  34  * Highlighting sets the bbox to ... some more.
  35  * Problem:  The bbox is the same for all views, but highlighting size should
  36  * depend on the zoom level.  The renderer obviously can figure out to make
  37  * it a few more pixels or something, but we need the bbox to also be
  38  * enlarged by a bit.  I guess the object_add_updates call must handle that,
  39  * as it knows about the conversion.
  40  */
  41
  42 static Color red = { 1.0, 0.0, 0.0 };
  43
  44 void
  45 highlight_object(DiaObject *obj, Color *col, Diagram *dia)
  46 {
  47   if (col)
  48     obj->highlight_color = col;
  49   else
  50     obj->highlight_color = &red;
  51
  52   object_add_updates(obj, dia);
  53 }
  54
  55 void
  56 highlight_object_off(DiaObject *obj, Diagram *dia)
  57 {
  58   if (obj->highlight_color != NULL) {
  59     /* Must add updates first, so we get the border erased. */
  60     object_add_updates(obj, dia);
  61     obj->highlight_color = NULL;
  62   }
  63 }
  64
  65 /** Resets all highlighting in this layer.  Helper function for
  66  * highlight_reset_all
  67  */
  68 static void
  69 highlight_reset_layer(Layer *layer, Diagram *dia)
  70 {
  71   GList *objects;
  72
  73   for (objects = layer->objects; objects != NULL;
  74        objects = g_list_next(objects)) {
  75     DiaObject *object = (DiaObject*)objects->data;
  76     highlight_object_off(object, dia);
  77   }
  78 }
  79
  80 /* Currently does a brute-force run-through of all objects.
  81  * If this is too slow, we could create a list of currently highlighted
  82  * objects in the diagram and traverse that before killing it.
  83  * Note that we're not assuming that all highlighted objects are in
  84  * the active layer.
  85  */
  86 void
  87 highlight_reset_all(Diagram *dia) {
  88   int i;
  89   for (i = 0; i < dia->data->layers->len; i++) {
  90     highlight_reset_layer((Layer*)g_ptr_array_index(dia->data->layers, i), dia);
  91   }
  92 }