[dia] Bug 108770 - text_margin allows to attach text with some distance

[Hans Breuer <hans src gnome org>]

commit 3ae43fb24714244efa978ffcb481817d836e5c9a
Author: Hans Breuer <hans breuer org>
Date:   Sat Jun 7 22:05:23 2014 +0200

    Bug 108770 - text_margin allows to attach text with some distance
    
    Some while ago discussed on dia-list
    https://mail.gnome.org/archives/dia-list/2014-March/msg00011.html
    a text_margin property to allow Text alignment with some distance.
    Also it is extending background fill by the margin. (With background
    drawing on the distance_from method is now using the bounding box
    e.g. for easier selection of text objects.
    I'm not completely satisfied with the behavior of not connected text,
    when the margin gets changed. It is currently moving the text although
    just increasing the margin should probably just keep the text position
    fixed and draw a bigger margin. OTOH this would make the object
    behavior dependent on it's connection state.

 objects/standard/textobj.c |   96 +++++++++++++++++++++++++++-----------------
 1 files changed, 59 insertions(+), 37 deletions(-)
---
diff --git a/objects/standard/textobj.c b/objects/standard/textobj.c
index 53abd72..a0a3d25 100644
--- a/objects/standard/textobj.c
+++ b/objects/standard/textobj.c
@@ -62,8 +62,10 @@ struct _Textobj {
   Valign vert_align;
   /*! bounding box filling */
   Color fill_color;
-  /*! backround to be filled or transparent */
+  /*! background to be filled or transparent */
   gboolean show_background;
+  /*! margin used for background drawing and connection point placement */
+  real margin;
 };
 
 static struct _TextobjProperties {
@@ -94,7 +96,7 @@ static void textobj_save(Textobj *textobj, ObjectNode obj_node,
 static DiaObject *textobj_load(ObjectNode obj_node, int version, DiaContext *ctx);
 static DiaMenu *textobj_get_object_menu(Textobj *textobj, Point *clickedpoint);
 
-static void textobj_valign_point(Textobj *textobj, Point* p, real factor);
+static void textobj_valign_point(Textobj *textobj, Point* p);
 
 static ObjectTypeOps textobj_type_ops =
 {
@@ -112,10 +114,11 @@ PropEnumData prop_text_vert_align_data[] = {
   { N_("First Line"), VALIGN_FIRST_LINE },
   { NULL, 0 }
 };
+static PropNumData text_margin_range = { 0.0, 10.0, 0.1 };
 static PropDescription textobj_props[] = {
   OBJECT_COMMON_PROPERTIES,
   PROP_STD_TEXT_ALIGNMENT,
-  { "text_vert_alignment", PROP_TYPE_ENUM, PROP_FLAG_VISIBLE | PROP_FLAG_OPTIONAL, \
+  { "text_vert_alignment", PROP_TYPE_ENUM, PROP_FLAG_VISIBLE | PROP_FLAG_OPTIONAL,
     N_("Vertical text alignment"), NULL, prop_text_vert_align_data },
   PROP_STD_TEXT_FONT,
   PROP_STD_TEXT_HEIGHT,
@@ -123,6 +126,8 @@ static PropDescription textobj_props[] = {
   PROP_STD_SAVED_TEXT,
   PROP_STD_FILL_COLOUR_OPTIONAL,
   PROP_STD_SHOW_BACKGROUND_OPTIONAL,
+  { "text_margin", PROP_TYPE_REAL,  PROP_FLAG_VISIBLE | PROP_FLAG_OPTIONAL,
+    N_("Text margin"), NULL, &text_margin_range }, 
   PROP_DESC_END
 };
 
@@ -136,6 +141,7 @@ static PropOffset textobj_offsets[] = {
   {"text_vert_alignment",PROP_TYPE_ENUM,offsetof(Textobj,vert_align)},
   { "fill_colour", PROP_TYPE_COLOUR, offsetof(Textobj, fill_color) },
   { "show_background", PROP_TYPE_BOOL, offsetof(Textobj, show_background) },
+  { "text_margin", PROP_TYPE_REAL, offsetof(Textobj, margin) },
   { NULL, 0, 0 }
 };
 
@@ -191,6 +197,8 @@ textobj_set_props(Textobj *textobj, GPtrArray *props)
 static real
 textobj_distance_from(Textobj *textobj, Point *point)
 {
+  if (textobj->show_background)
+    return distance_rectangle_point(&textobj->object.bounding_box, point);
   return text_distance_from(textobj->text, point); 
 }
 
@@ -202,8 +210,6 @@ textobj_select(Textobj *textobj, Point *clicked_point,
   text_grab_focus(textobj->text, &textobj->object);
 }
 
-
-
 static ObjectChange*
 textobj_move_handle(Textobj *textobj, Handle *handle,
                    Point *to, ConnectionPoint *cp,
@@ -214,12 +220,7 @@ textobj_move_handle(Textobj *textobj, Handle *handle,
   assert(to!=NULL);
 
   if (handle->id == HANDLE_TEXT) {
-          /*Point to2 = *to;
-          point_add(&to2,&textobj->text->position);
-          point_sub(&to2,&textobj->text_handle.pos);
-          textobj_move(textobj, &to2);*/
-          textobj_move(textobj, to);
-          
+    textobj_move(textobj, to);
   }
 
   return NULL;
@@ -245,36 +246,36 @@ textobj_draw(Textobj *textobj, DiaRenderer *renderer)
     Rectangle box;
     Point ul, lr;
     text_calc_boundingbox (textobj->text, &box);
-    ul.x = box.left;
-    ul.y = box.top;
-    lr.x = box.right;
-    lr.y = box.bottom;
+    ul.x = box.left - textobj->margin;
+    ul.y = box.top - textobj->margin;
+    lr.x = box.right + textobj->margin;
+    lr.y = box.bottom + textobj->margin;
     DIA_RENDERER_GET_CLASS (renderer)->draw_rect (renderer, &ul, &lr, &textobj->fill_color, NULL);
   }
   text_draw(textobj->text, renderer);
 }
 
-static void textobj_valign_point(Textobj *textobj, Point* p, real factor)
-        /* factor should be 1 or -1 */
+static void
+textobj_valign_point(Textobj *textobj, Point* p)
 {
-    Rectangle *bb  = &(textobj->object.bounding_box); 
-    real offset ;
-    switch (textobj->vert_align){
-        case VALIGN_BOTTOM:
-            offset = bb->bottom - textobj->object.position.y;
-            p->y -= offset * factor; 
-            break;
-        case VALIGN_TOP:
-            offset = bb->top - textobj->object.position.y;
-            p->y -= offset * factor; 
-            break;
-        case VALIGN_CENTER:
-            offset = (bb->bottom + bb->top)/2 - textobj->object.position.y;
-            p->y -= offset * factor; 
-            break;
-        case VALIGN_FIRST_LINE:
-            break;
-        }
+  Rectangle *bb  = &(textobj->object.bounding_box); 
+  real offset;
+  switch (textobj->vert_align){
+  case VALIGN_BOTTOM:
+    offset = bb->bottom - textobj->object.position.y;
+    p->y -= offset; 
+    break;
+  case VALIGN_TOP:
+    offset = bb->top - textobj->object.position.y;
+    p->y -= offset; 
+    break;
+  case VALIGN_CENTER:
+    offset = (bb->bottom + bb->top)/2 - textobj->object.position.y;
+    p->y -= offset; 
+    break;
+  case VALIGN_FIRST_LINE:
+    break;
+  }
 }
 static void
 textobj_update_data(Textobj *textobj)
@@ -286,10 +287,24 @@ textobj_update_data(Textobj *textobj)
   text_calc_boundingbox(textobj->text, &obj->bounding_box);
 
   to2 = obj->position;
-  textobj_valign_point(textobj, &to2, 1);
+  textobj_valign_point(textobj, &to2);
+  /* shift text position depending on text alignment */
+  if (VALIGN_TOP == textobj->vert_align)
+    to2.y += textobj->margin; /* down */
+  else if (VALIGN_BOTTOM == textobj->vert_align)
+    to2.y -= textobj->margin; /* up */
+  if (ALIGN_LEFT == textobj->text->alignment)
+    to2.x += textobj->margin; /* right */
+  else if (ALIGN_RIGHT == textobj->text->alignment)
+    to2.x -= textobj->margin; /* left */
   text_set_position(textobj->text, &to2);
   text_calc_boundingbox(textobj->text, &obj->bounding_box);
-  
+  /* grow the bounding box by 2x margin */
+  obj->bounding_box.top    -= textobj->margin;
+  obj->bounding_box.left   -= textobj->margin;
+  obj->bounding_box.bottom += textobj->margin;
+  obj->bounding_box.right  += textobj->margin;
+
   textobj->text_handle.pos = obj->position;
 }
 
@@ -333,6 +348,8 @@ textobj_create(Point *startpoint,
   textobj->text_handle.type = HANDLE_MAJOR_CONTROL;
   textobj->text_handle.connect_type = HANDLE_CONNECTABLE;
   textobj->text_handle.connected_to = NULL;
+  /* no margin till Dia 0.98 */
+  textobj->margin = 0.0;
 
   textobj_update_data(textobj);
 
@@ -362,6 +379,8 @@ textobj_save(Textobj *textobj, ObjectNode obj_node, DiaContext *ctx)
     data_add_color(new_attribute(obj_node, "fill_color"), &textobj->fill_color, ctx);
     data_add_boolean(new_attribute(obj_node, "show_background"), textobj->show_background, ctx);
   }
+  if (textobj->margin > 0.0)
+    data_add_real(new_attribute(obj_node, "margin"), textobj->margin, ctx);
 }
 
 static DiaObject *
@@ -407,6 +426,9 @@ textobj_load(ObjectNode obj_node, int version, DiaContext *ctx)
     textobj->show_background = data_boolean(attribute_first_data(attr), ctx);
   else
     textobj->show_background = FALSE;
+  attr = object_find_attribute(obj_node, "margin");
+  if (attr)
+    textobj->margin = data_real(attribute_first_data(attr), ctx);
 
   object_init(obj, 1, 0);