Introduce LdRectangle, LdPoint and LdPointArray.

Remove LdCanvasRect and LdSymbolArea.

12 files changed, 344 insertions, 147 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fc9bfc6..493904f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -82,6 +82,7 @@ set (project_DOC_DIR "${CMAKE_CURRENT_SOURCE_DIR}/docs/reference")
 set (logdiag_SOURCES
 	src/logdiag.c
 	src/ld-marshal.c
+	src/ld-types.c
 	src/ld-window-main.c
 	src/ld-diagram.c
 	src/ld-diagram-object.c
@@ -95,6 +96,7 @@ set (logdiag_SOURCES
 set (logdiag_HEADERS
 	${CMAKE_CURRENT_BINARY_DIR}/config.h
 	src/ld-marshal.h
+	src/ld-types.h
 	src/ld-window-main.h
 	src/ld-diagram.h
 	src/ld-diagram-object.h
diff --git a/src/ld-canvas.c b/src/ld-canvas.c
index 0acac75..aa6a1b3 100644
--- a/src/ld-canvas.c
+++ b/src/ld-canvas.c
@@ -15,6 +15,7 @@
 #include "config.h"
 
 #include "ld-marshal.h"
+#include "ld-types.h"
 #include "ld-diagram-object.h"
 #include "ld-diagram-symbol.h"
 #include "ld-diagram.h"
@@ -83,8 +84,6 @@ struct _LdCanvasColor
 	gdouble a;
 };
 
-typedef cairo_rectangle_t LdCanvasRect;
-
 /*
  * LdCanvasPrivate:
  * @diagram: A diagram object assigned to this canvas as a model.
@@ -138,7 +137,7 @@ struct _DrawData
 {
 	LdCanvas *self;
 	cairo_t *cr;
-	LdCanvasRect exposed_rect;
+	LdRectangle exposed_rect;
 	gdouble scale;
 };
 
@@ -181,12 +180,6 @@ static void ld_canvas_color_set (LdCanvasColor *color,
 	gdouble r, gdouble g, gdouble b, gdouble a);
 static void ld_canvas_color_apply (LdCanvasColor *color, cairo_t *cr);
 
-static gboolean ld_canvas_rect_contains (LdCanvasRect *rect,
-	gdouble x, gdouble y);
-static gboolean ld_canvas_rect_intersects (LdCanvasRect *first,
-	LdCanvasRect *second);
-static void ld_canvas_rect_extend (LdCanvasRect *rect, gdouble border);
-
 static void move_object_to_coords (LdCanvas *self, LdDiagramObject *object,
 	gdouble x, gdouble y);
 static LdDiagramObject *get_object_at_coords (LdCanvas *self,
@@ -195,11 +188,11 @@ static gboolean is_object_selected (LdCanvas *self, LdDiagramObject *object);
 static LdSymbol *resolve_diagram_symbol (LdCanvas *self,
 	LdDiagramSymbol *diagram_symbol);
 static gboolean get_symbol_area (LdCanvas *self, LdDiagramSymbol *symbol,
-	LdCanvasRect *rect);
+	LdRectangle *rect);
 static gboolean get_symbol_clip_area (LdCanvas *self, LdDiagramSymbol *symbol,
-	LdCanvasRect *rect);
+	LdRectangle *rect);
 static gboolean get_object_area (LdCanvas *self, LdDiagramObject *object,
-	LdCanvasRect *rect);
+	LdRectangle *rect);
 static gboolean object_hit_test (LdCanvas *self, LdDiagramObject *object,
 	gdouble x, gdouble y);
 static void queue_object_redraw (LdCanvas *self, LdDiagramObject *object);
@@ -792,37 +785,6 @@ ld_canvas_color_apply (LdCanvasColor *color, cairo_t *cr)
 	cairo_set_source_rgba (cr, color->r, color->g, color->b, color->a);
 }
 
-static gboolean
-ld_canvas_rect_contains (LdCanvasRect *rect, gdouble x, gdouble y)
-{
-	g_return_val_if_fail (rect != NULL, FALSE);
-	return (x >= rect->x && x <= rect->x + rect->width
-	     && y >= rect->y && y <= rect->y + rect->height);
-}
-
-static gboolean
-ld_canvas_rect_intersects (LdCanvasRect *first, LdCanvasRect *second)
-{
-	g_return_val_if_fail (first != NULL, FALSE);
-	g_return_val_if_fail (second != NULL, FALSE);
-
-	return !(first->x > second->x + second->width
-	      || first->y > second->y + second->height
-	      || first->x + first->width  < second->x
-	      || first->y + first->height < second->y);
-}
-
-static void
-ld_canvas_rect_extend (LdCanvasRect *rect, gdouble border)
-{
-	g_return_if_fail (rect != NULL);
-
-	rect->x -= border;
-	rect->y -= border;
-	rect->width  += 2 * border;
-	rect->height += 2 * border;
-}
-
 static void
 move_object_to_coords (LdCanvas *self, LdDiagramObject *object,
 	gdouble x, gdouble y)
@@ -870,12 +832,12 @@ resolve_diagram_symbol (LdCanvas *self, LdDiagramSymbol *diagram_symbol)
 }
 
 static gboolean
-get_symbol_area (LdCanvas *self, LdDiagramSymbol *symbol, LdCanvasRect *rect)
+get_symbol_area (LdCanvas *self, LdDiagramSymbol *symbol, LdRectangle *rect)
 {
 	LdDiagramObject *object;
 	gdouble object_x, object_y;
 	LdSymbol *library_symbol;
-	LdSymbolArea area;
+	LdRectangle area;
 	gdouble x1, x2;
 	gdouble y1, y2;
 
@@ -908,20 +870,20 @@ get_symbol_area (LdCanvas *self, LdDiagramSymbol *symbol, LdCanvasRect *rect)
 
 static gboolean
 get_symbol_clip_area (LdCanvas *self, LdDiagramSymbol *symbol,
-	LdCanvasRect *rect)
+	LdRectangle *rect)
 {
-	LdCanvasRect object_rect;
+	LdRectangle object_rect;
 
 	if (!get_object_area (self, LD_DIAGRAM_OBJECT (symbol), &object_rect))
 		return FALSE;
 
 	*rect = object_rect;
-	ld_canvas_rect_extend (rect, SYMBOL_CLIP_TOLERANCE);
+	ld_rectangle_extend (rect, SYMBOL_CLIP_TOLERANCE);
 	return TRUE;
 }
 
 static gboolean
-get_object_area (LdCanvas *self, LdDiagramObject *object, LdCanvasRect *rect)
+get_object_area (LdCanvas *self, LdDiagramObject *object, LdRectangle *rect)
 {
 	if (LD_IS_DIAGRAM_SYMBOL (object))
 		return get_symbol_area (self, LD_DIAGRAM_SYMBOL (object), rect);
@@ -931,12 +893,12 @@ get_object_area (LdCanvas *self, LdDiagramObject *object, LdCanvasRect *rect)
 static gboolean
 object_hit_test (LdCanvas *self, LdDiagramObject *object, gdouble x, gdouble y)
 {
-	LdCanvasRect rect;
+	LdRectangle rect;
 
 	if (!get_object_area (self, object, &rect))
 		return FALSE;
-	ld_canvas_rect_extend (&rect, OBJECT_BORDER_TOLERANCE);
-	return ld_canvas_rect_contains (&rect, x, y);
+	ld_rectangle_extend (&rect, OBJECT_BORDER_TOLERANCE);
+	return ld_rectangle_contains (&rect, x, y);
 }
 
 static void
@@ -944,7 +906,7 @@ queue_object_redraw (LdCanvas *self, LdDiagramObject *object)
 {
 	if (LD_IS_DIAGRAM_SYMBOL (object))
 	{
-		LdCanvasRect rect;
+		LdRectangle rect;
 
 		if (!get_symbol_clip_area (self, LD_DIAGRAM_SYMBOL (object), &rect))
 			return;
@@ -1151,7 +1113,7 @@ static void
 draw_symbol (LdDiagramSymbol *diagram_symbol, DrawData *data)
 {
 	LdSymbol *symbol;
-	LdCanvasRect clip_rect;
+	LdRectangle clip_rect;
 	gdouble x, y;
 
 	symbol = resolve_diagram_symbol (data->self, diagram_symbol);
@@ -1165,7 +1127,7 @@ draw_symbol (LdDiagramSymbol *diagram_symbol, DrawData *data)
 	}
 
 	if (!get_symbol_clip_area (data->self, diagram_symbol, &clip_rect)
-		|| !ld_canvas_rect_intersects (&clip_rect, &data->exposed_rect))
+		|| !ld_rectangle_intersects (&clip_rect, &data->exposed_rect))
 		return;
 
 	cairo_save (data->cr);
diff --git a/src/ld-library.c b/src/ld-library.c
index 73c40ef..5e4d502 100644
--- a/src/ld-library.c
+++ b/src/ld-library.c
@@ -2,7 +2,7 @@
  * ld-library.c
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -15,6 +15,7 @@
 
 #include "config.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-symbol-category.h"
 #include "ld-library.h"
diff --git a/src/ld-lua-symbol-private.h b/src/ld-lua-symbol-private.h
index 73bed20..0e8800e 100644
--- a/src/ld-lua-symbol-private.h
+++ b/src/ld-lua-symbol-private.h
@@ -2,7 +2,7 @@
  * ld-lua-symbol-private.h
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -28,7 +28,7 @@ struct _LdLuaSymbolPrivate
 	LdLua *lua;
 	gchar *name;
 	gchar *human_name;
-	LdSymbolArea area;
+	LdRectangle area;
 };
 
 
diff --git a/src/ld-lua-symbol.c b/src/ld-lua-symbol.c
index 5626761..a481cff 100644
--- a/src/ld-lua-symbol.c
+++ b/src/ld-lua-symbol.c
@@ -2,7 +2,7 @@
  * ld-lua-symbol.c
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -12,6 +12,7 @@
 
 #include "config.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-symbol-category.h"
 #include "ld-library.h"
@@ -35,7 +36,7 @@ static void ld_lua_symbol_finalize (GObject *gobject);
 
 static const gchar *ld_lua_symbol_real_get_name (LdSymbol *symbol);
 static const gchar *ld_lua_symbol_real_get_human_name (LdSymbol *symbol);
-static void ld_lua_symbol_real_get_area (LdSymbol *symbol, LdSymbolArea *area);
+static void ld_lua_symbol_real_get_area (LdSymbol *symbol, LdRectangle *area);
 static void ld_lua_symbol_real_draw (LdSymbol *symbol, cairo_t *cr);
 
 
@@ -102,7 +103,7 @@ ld_lua_symbol_real_get_human_name (LdSymbol *symbol)
 }
 
 static void
-ld_lua_symbol_real_get_area (LdSymbol *symbol, LdSymbolArea *area)
+ld_lua_symbol_real_get_area (LdSymbol *symbol, LdRectangle *area)
 {
 	LdLuaSymbol *self;
 
diff --git a/src/ld-lua.c b/src/ld-lua.c
index 4cab71c..746d2f9 100644
--- a/src/ld-lua.c
+++ b/src/ld-lua.c
@@ -15,6 +15,7 @@
 
 #include "config.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-library.h"
 
@@ -90,7 +91,7 @@ static int ld_lua_private_unregister_cb (lua_State *L);
 static int ld_lua_logdiag_register (lua_State *L);
 static int process_registration (lua_State *L);
 static gchar *get_translation (lua_State *L, int index);
-static gboolean read_symbol_area (lua_State *L, int index, LdSymbolArea *area);
+static gboolean read_symbol_area (lua_State *L, int index, LdRectangle *area);
 
 static void push_cairo_object (lua_State *L, LdLuaDrawData *draw_data);
 static gdouble get_cairo_scale (cairo_t *cr);
@@ -528,7 +529,7 @@ get_translation (lua_State *L, int index)
  * Return value: TRUE on success, FALSE on failure.
  */
 static gboolean
-read_symbol_area (lua_State *L, int index, LdSymbolArea *area)
+read_symbol_area (lua_State *L, int index, LdRectangle *area)
 {
 	lua_Number x1, x2, y1, y2;
 
diff --git a/src/ld-symbol-category.c b/src/ld-symbol-category.c
index 2ca2693..b9d70b1 100644
--- a/src/ld-symbol-category.c
+++ b/src/ld-symbol-category.c
@@ -2,7 +2,7 @@
  * ld-symbol-category.c
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -12,6 +12,7 @@
 
 #include "config.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-symbol-category.h"
 #include "ld-library.h"
diff --git a/src/ld-symbol.c b/src/ld-symbol.c
index 45f11c9..24a7ab9 100644
--- a/src/ld-symbol.c
+++ b/src/ld-symbol.c
@@ -2,7 +2,7 @@
  * ld-symbol.c
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -12,6 +12,7 @@
 
 #include "config.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-symbol-category.h"
 #include "ld-library.h"
@@ -82,7 +83,7 @@ ld_symbol_class_init (LdSymbolClass *klass)
  */
 	pspec = g_param_spec_boxed ("area", "Area",
 		"The area of this symbol.",
-		LD_TYPE_SYMBOL_AREA, G_PARAM_READABLE);
+		LD_TYPE_RECTANGLE, G_PARAM_READABLE);
 	g_object_class_install_property (object_class, PROP_AREA, pspec);
 }
 
@@ -108,7 +109,7 @@ ld_symbol_get_property (GObject *object, guint property_id,
 		break;
 	case PROP_AREA:
 		{
-			LdSymbolArea area;
+			LdRectangle area;
 
 			ld_symbol_get_area (self, &area);
 			g_value_set_boxed (value, &area);
@@ -171,7 +172,7 @@ ld_symbol_get_human_name (LdSymbol *self)
  * Get the area of the symbol.
  */
 void
-ld_symbol_get_area (LdSymbol *self, LdSymbolArea *area)
+ld_symbol_get_area (LdSymbol *self, LdRectangle *area)
 {
 	LdSymbolClass *klass;
 
@@ -202,51 +203,3 @@ ld_symbol_draw (LdSymbol *self, cairo_t *cr)
 	g_return_if_fail (klass->draw != NULL);
 	klass->draw (self, cr);
 }
-
-/**
- * ld_symbol_area_copy:
- * @self: An #LdSymbolArea structure.
- *
- * Makes a copy of the structure.
- * The result must be freed by ld_symbol_area_free().
- *
- * Return value: A copy of @self.
- **/
-LdSymbolArea *
-ld_symbol_area_copy (const LdSymbolArea *self)
-{
-	LdSymbolArea *new_area;
-
-	g_return_val_if_fail (self != NULL, NULL);
-
-	new_area = g_slice_new (LdSymbolArea);
-	*new_area = *self;
-	return new_area;
-}
-
-/**
- * ld_symbol_area_free:
- * @self: An #LdSymbolArea structure.
- *
- * Frees the structure created with ld_symbol_area_copy().
- **/
-void
-ld_symbol_area_free (LdSymbolArea *self)
-{
-	g_return_if_fail (self != NULL);
-
-	g_slice_free (LdSymbolArea, self);
-}
-
-GType
-ld_symbol_area_get_type (void)
-{
-	static GType our_type = 0;
-
-	if (our_type == 0)
-		our_type = g_boxed_type_register_static
-			(g_intern_static_string ("LdSymbolArea"),
-			(GBoxedCopyFunc) ld_symbol_area_copy,
-			(GBoxedFreeFunc) ld_symbol_area_free);
-	return our_type;
-}
diff --git a/src/ld-symbol.h b/src/ld-symbol.h
index 0290720..43ab4df 100644
--- a/src/ld-symbol.h
+++ b/src/ld-symbol.h
@@ -2,7 +2,7 @@
  * ld-symbol.h
  *
  * This file is a part of logdiag.
- * Copyright Přemysl Janouch 2010. All rights reserved.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
  *
  * See the file LICENSE for licensing information.
  *
@@ -14,33 +14,6 @@
 G_BEGIN_DECLS
 
 
-#define LD_TYPE_SYMBOL_AREA (ld_symbol_area_get_type ())
-
-typedef struct _LdSymbolArea LdSymbolArea;
-
-/**
- * LdSymbolArea:
- * @x: Left-top X coordinate.
- * @y: Left-top Y coordinate.
- * @width: Width of the area, must be positive.
- * @height: Height of the area, must be positive.
- *
- * Defines the area of the symbol relative to the center of the symbol,
- * which is at the (0, 0) coordinates.
- */
-struct _LdSymbolArea
-{
-	gdouble x, y;
-	gdouble width, height;
-};
-
-
-GType ld_symbol_area_get_type (void) G_GNUC_CONST;
-
-LdSymbolArea *ld_symbol_area_copy (const LdSymbolArea *self);
-void ld_symbol_area_free (LdSymbolArea *self);
-
-
 #define LD_TYPE_SYMBOL (ld_symbol_get_type ())
 #define LD_SYMBOL(obj) (G_TYPE_CHECK_INSTANCE_CAST \
 	((obj), LD_TYPE_SYMBOL, LdSymbol))
@@ -79,7 +52,7 @@ struct _LdSymbolClass
 
 	const gchar *(*get_name) (LdSymbol *self);
 	const gchar *(*get_human_name) (LdSymbol *self);
-	void (*get_area) (LdSymbol *self, LdSymbolArea *area);
+	void (*get_area) (LdSymbol *self, LdRectangle *area);
 	void (*draw) (LdSymbol *self, cairo_t *cr);
 };
 
@@ -88,7 +61,7 @@ GType ld_symbol_get_type (void) G_GNUC_CONST;
 
 const gchar *ld_symbol_get_name (LdSymbol *self);
 const gchar *ld_symbol_get_human_name (LdSymbol *self);
-void ld_symbol_get_area (LdSymbol *self, LdSymbolArea *area);
+void ld_symbol_get_area (LdSymbol *self, LdRectangle *area);
 void ld_symbol_draw (LdSymbol *self, cairo_t *cr);
 
 /* TODO: Interface for terminals.
diff --git a/src/ld-types.c b/src/ld-types.c
new file mode 100644
index 0000000..512bcef
--- /dev/null
+++ b/src/ld-types.c
@@ -0,0 +1,202 @@
+/*
+ * ld-types.c
+ *
+ * This file is a part of logdiag.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
+ *
+ * See the file LICENSE for licensing information.
+ *
+ */
+
+#include <gtk/gtk.h>
+
+#include "config.h"
+
+#include "ld-types.h"
+
+
+#define DEFINE_BOXED_TYPE(TypeName, type_name) \
+GType \
+type_name ## _get_type (void) \
+{ \
+	static GType our_type = 0; \
+	if (our_type == 0) \
+		our_type = g_boxed_type_register_static \
+			(g_intern_static_string (#TypeName), \
+			(GBoxedCopyFunc) type_name ## _copy, \
+			(GBoxedFreeFunc) type_name ## _free); \
+	return our_type; \
+}
+
+DEFINE_BOXED_TYPE (LdPoint, ld_point)
+DEFINE_BOXED_TYPE (LdPointArray, ld_point_array)
+DEFINE_BOXED_TYPE (LdRectangle, ld_rectangle)
+
+#define DEFINE_BOXED_TRIVIAL_COPY(TypeName, type_name) \
+TypeName * \
+type_name ## _copy (const TypeName *self) \
+{ \
+	TypeName *new_copy; \
+	g_return_val_if_fail (self != NULL, NULL); \
+	new_copy = g_slice_new (TypeName); \
+	*new_copy = *self; \
+	return new_copy; \
+}
+
+#define DEFINE_BOXED_TRIVIAL_FREE(TypeName, type_name) \
+void \
+type_name ## _free (TypeName *self) \
+{ \
+	g_return_if_fail (self != NULL); \
+	g_slice_free (TypeName, self); \
+}
+
+/**
+ * ld_point_copy:
+ * @self: An #LdPoint structure.
+ *
+ * Makes a copy of the structure.
+ * The result must be freed by ld_point_free().
+ *
+ * Return value: A copy of @self.
+ */
+DEFINE_BOXED_TRIVIAL_COPY (LdPoint, ld_point)
+
+/**
+ * ld_point_free:
+ * @self: An #LdPoint structure.
+ *
+ * Frees the structure created with ld_point_copy().
+ */
+DEFINE_BOXED_TRIVIAL_FREE (LdPoint, ld_point)
+
+/**
+ * ld_point_array_new:
+ * @num_points: The number of points the array can store.
+ *
+ * Create a new array of points and initialize.
+ *
+ * Return value: An #LdPointArray structure.
+ */
+LdPointArray *
+ld_point_array_new (gint num_points)
+{
+	LdPointArray *new_array;
+
+	g_return_val_if_fail (num_points >= 1, NULL);
+
+	new_array = g_slice_new (LdPointArray);
+	new_array->num_points = num_points;
+	new_array->points = g_malloc0 (num_points * sizeof (LdPoint));
+	return new_array;
+}
+
+/**
+ * ld_point_array_copy:
+ * @self: An #LdPointArray structure.
+ *
+ * Makes a copy of the structure.
+ * The result must be freed by ld_point_array_free().
+ *
+ * Return value: A copy of @self.
+ */
+LdPointArray *
+ld_point_array_copy (const LdPointArray *self)
+{
+	LdPointArray *new_array;
+
+	g_return_val_if_fail (self != NULL, NULL);
+
+	new_array = g_slice_new (LdPointArray);
+	new_array->num_points = self->num_points;
+	new_array->points = g_memdup (self->points,
+		self->num_points * sizeof (LdPoint));
+	return new_array;
+}
+
+/**
+ * ld_point_array_free:
+ * @self: An #LdPointArray structure.
+ *
+ * Frees the structure created with ld_point_array_copy().
+ */
+void
+ld_point_array_free (LdPointArray *self)
+{
+	g_return_if_fail (self != NULL);
+
+	g_free (self->points);
+	g_slice_free (LdPointArray, self);
+}
+
+/**
+ * ld_rectangle_copy:
+ * @self: An #LdRectangle structure.
+ *
+ * Makes a copy of the structure.
+ * The result must be freed by ld_rectangle_free().
+ *
+ * Return value: A copy of @self.
+ */
+DEFINE_BOXED_TRIVIAL_COPY (LdRectangle, ld_rectangle)
+
+/**
+ * ld_rectangle_free:
+ * @self: An #LdRectangle structure.
+ *
+ * Frees the structure created with ld_rectangle_copy().
+ */
+DEFINE_BOXED_TRIVIAL_FREE (LdRectangle, ld_rectangle)
+
+/**
+ * ld_rectangle_contains:
+ * @self: An #LdRectangle structure.
+ * @x: The X coordinate of the point to be checked.
+ * @y: The Y coordinate of the point to be checked.
+ *
+ * Return value: TRUE if the rectangle contains the specified point.
+ */
+gboolean
+ld_rectangle_contains (LdRectangle *self, gdouble x, gdouble y)
+{
+	g_return_val_if_fail (self != NULL, FALSE);
+	return (x >= self->x && x <= self->x + self->width
+	     && y >= self->y && y <= self->y + self->height);
+}
+
+/**
+ * ld_rectangle_intersects:
+ * @self: An #LdRectangle structure.
+ * @rect: An #LdRectangle to be checked for intersection.
+ *
+ * Return value: TRUE if the two rectangles intersect.
+ */
+gboolean
+ld_rectangle_intersects (LdRectangle *self, LdRectangle *rect)
+{
+	g_return_val_if_fail (self != NULL, FALSE);
+	g_return_val_if_fail (rect != NULL, FALSE);
+
+	return !(self->x > rect->x + rect->width
+	      || self->y > rect->y + rect->height
+	      || self->x + self->width  < rect->x
+	      || self->y + self->height < rect->y);
+}
+
+/**
+ * ld_rectangle_extend:
+ * @self: An #LdRectangle structure.
+ * @border: The border by which the rectangle should be extended.
+ *
+ * Extend a rectangle on all sides.
+ */
+void
+ld_rectangle_extend (LdRectangle *self, gdouble border)
+{
+	g_return_if_fail (self != NULL);
+
+	self->x -= border;
+	self->y -= border;
+	self->width  += 2 * border;
+	self->height += 2 * border;
+}
diff --git a/src/ld-types.h b/src/ld-types.h
new file mode 100644
index 0000000..6837f74
--- /dev/null
+++ b/src/ld-types.h
@@ -0,0 +1,100 @@
+/*
+ * ld-types.h
+ *
+ * This file is a part of logdiag.
+ * Copyright Přemysl Janouch 2010 - 2011. All rights reserved.
+ *
+ * See the file LICENSE for licensing information.
+ *
+ */
+
+#ifndef __LD_TYPES_H__
+#define __LD_TYPES_H__
+
+G_BEGIN_DECLS
+
+
+/**
+ * SECTION:ld-types
+ * @short_description: Simple data types.
+ *
+ * #LdPoint defines coordinates of a point.
+ *
+ * #LdRectangle defines the position and size of a rectangle.
+ */
+
+#define LD_TYPE_POINT (ld_point_get_type ())
+#define LD_TYPE_POINT_ARRAY (ld_point_array_get_type ())
+#define LD_TYPE_RECTANGLE (ld_rectangle_get_type ())
+
+typedef struct _LdPoint LdPoint;
+typedef struct _LdPointArray LdPointArray;
+typedef struct _LdRectangle LdRectangle;
+
+
+/**
+ * LdPoint:
+ * @x: The X coordinate.
+ * @y: The Y coordinate.
+ *
+ * Defines a point.
+ */
+struct _LdPoint
+{
+	gdouble x, y;
+};
+
+GType ld_point_get_type (void) G_GNUC_CONST;
+
+LdPoint *ld_point_copy (const LdPoint *self);
+void ld_point_free (LdPoint *self);
+
+
+/**
+ * LdPointArray:
+ * @points: An array of #LdPoint structures.
+ * @num_points: Count of points in @points.
+ *
+ * Moves quickly.
+ */
+struct _LdPointArray
+{
+	LdPoint *points;
+	gint num_points;
+};
+
+GType ld_point_array_get_type (void) G_GNUC_CONST;
+
+LdPointArray *ld_point_array_new (gint num_points);
+LdPointArray *ld_point_array_copy (const LdPointArray *self);
+void ld_point_array_free (LdPointArray *self);
+
+
+/**
+ * LdRectangle:
+ * @x: Left-top X coordinate.
+ * @y: Left-top Y coordinate.
+ * @width: Width of the area, must be positive.
+ * @height: Height of the area, must be positive.
+ *
+ * Defines a rectangle.
+ */
+struct _LdRectangle
+{
+	gdouble x, y;
+	gdouble width, height;
+};
+
+GType ld_rectangle_get_type (void) G_GNUC_CONST;
+
+LdRectangle *ld_rectangle_copy (const LdRectangle *self);
+void ld_rectangle_free (LdRectangle *self);
+gboolean ld_rectangle_contains (LdRectangle *self, gdouble x, gdouble y);
+gboolean ld_rectangle_intersects (LdRectangle *self, LdRectangle *rect);
+void ld_rectangle_extend (LdRectangle *self, gdouble border);
+
+
+G_END_DECLS
+
+#endif /* ! __LD_TYPES_H__ */
+
diff --git a/src/ld-window-main.c b/src/ld-window-main.c
index 366dbf0..d22f400 100644
--- a/src/ld-window-main.c
+++ b/src/ld-window-main.c
@@ -14,6 +14,7 @@
 
 #include "ld-window-main.h"
 
+#include "ld-types.h"
 #include "ld-symbol.h"
 #include "ld-symbol-category.h"
 #include "ld-library.h"
@@ -610,7 +611,7 @@ on_category_toggle (GtkToggleButton *toggle_button, gpointer user_data)
 		for (symbol_iter = children; symbol_iter;
 			symbol_iter = symbol_iter->next)
 		{
-			LdSymbolArea area;
+			LdRectangle area;
 
 			item->symbol = LD_SYMBOL (symbol_iter->data);
 			g_object_ref (item->symbol);