include/pwlib/region.h

   1 /*
   2  * region.h
   3  *
   4  * Arbitrarily shaped region.
   5  *
   6  * Portable Windows Library
   7  *
   8  * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
   9  *
  10  * The contents of this file are subject to the Mozilla Public License
  11  * Version 1.0 (the "License"); you may not use this file except in
  12  * compliance with the License. You may obtain a copy of the License at
  13  * http://www.mozilla.org/MPL/
  14  *
  15  * Software distributed under the License is distributed on an "AS IS"
  16  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  17  * the License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * The Original Code is Portable Windows Library.
  21  *
  22  * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
  23  *
  24  * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
  25  * All Rights Reserved.
  26  *
  27  * Contributor(s): ______________________________________.
  28  *
  29  * $Log$
  30  * Revision 1.15  2001/05/22 12:49:33  robertj
  31  * Did some seriously wierd rewrite of platform headers to eliminate the
  32  *   stupid GNU compiler warning about braces not matching.
  33  *
  34  * Revision 1.14  1999/03/10 03:49:53  robertj
  35  * More documentation adjustments.
  36  *
  37  * Revision 1.13  1999/03/09 08:01:49  robertj
  38  * Changed comments for doc++ support (more to come).
  39  *
  40  * Revision 1.12  1999/02/16 08:08:46  robertj
  41  * MSVC 6.0 compatibility changes.
  42  *
  43  * Revision 1.11  1998/09/23 06:28:48  robertj
  44  * Added open source copyright license.
  45  *
  46  * Revision 1.10  1995/03/14 12:42:25  robertj
  47  * Updated documentation to use HTML codes.
  48  *
  49  * Revision 1.9  1995/01/14  06:19:30  robertj
  50  * Documentation
  51  *
  52  * Revision 1.8  1994/08/23  11:32:52  robertj
  53  * Oops
  54  *
  55  * Revision 1.7  1994/08/22  00:46:48  robertj
  56  * Added pragma fro GNU C++ compiler.
  57  *
  58  * Revision 1.6  1994/01/03  04:42:23  robertj
  59  * Mass changes to common container classes and interactors etc etc etc.
  60  *
  61  * Revision 1.5  1993/12/06  22:06:45  robertj
  62  * Destructor should be virtual for classes with virtual member functions.
  63  *
  64  * Revision 1.4  1993/10/16  20:33:20  robertj
  65  * Added function to determine if a rectangle and region overlap.
  66  *
  67  * Revision 1.3  1993/08/21  01:50:33  robertj
  68  * Made Clone() function optional, default will assert if called.
  69  *
  70  * Revision 1.2  1993/07/14  12:49:16  robertj
  71  * Fixed RCS keywords.
  72  *
  73  */
  74
  75
  76 #define _PREGION
  77
  78 #ifdef __GNUC__
  79 #pragma interface
  80 #endif
  81
  82
  83 /**A class representing a region of the graphics system drawing plane. This
  84    is an arbitrary enclosed shape. It is often made up from a collection of
  85    rectangles.
  86  */
  87 class PRegion : public PObject
  88 {
  89   PCLASSINFO(PRegion, PObject);
  90
  91   public:
  92    /**Create new region object. The first, parameterless, constructor creates
  93        an empty region. The second creates a region that initially encloses
  94        the specified rectangle.
  95      */
  96     PRegion();
  97     PRegion(
  98       const PRect & rect    /// Rectangle for initial region.
  99     );
 100
 101     /** Create a copy of the specified region. */
 102     PRegion(
 103       const PRegion & rgn   /// Region to copy.
 104     );
 105
 106     /** Assign one region to another. */
 107     PRegion & operator=(
 108       const PRegion & rgn   /// Region to assign to the current region.
 109     );
 110
 111     /** Destroy the region. */
 112     virtual ~PRegion();
 113
 114
 115   /**@name Overrides from class PObject */
 116    /**Determine if the two regions are identical.
 117
 118        @return
 119        #EqualTo# if the regions enclose the identical part of the
 120        drawing plane, otherwise #GreaterThan# is returned.
 121      */
 122     virtual Comparison Compare(
 123       const PObject & obj   /// Region to compare against.
 124     ) const;
 125
 126
 127   /**@name New functions for class */
 128    /**Add the specified area of the drawing plane to the region. The region
 129        will include the area specified into its enclosed space.
 130      */
 131     void Add(
 132       const PRect & rect    /// Rectangle to add to teh region.
 133     );
 134     void Add(
 135       const PRegion & rgn   /// Another region to add to region.
 136     );
 137
 138    /**Determine if the point is contined within the regions space.
 139
 140        @return
 141        TRUE if point is in region.
 142      */
 143     BOOL ContainsPoint(
 144       const PPoint & pt   /// Point to determine if is inside region.
 145     ) const;
 146
 147    /**Determine if the rectangle is wholly contiained within the region.
 148
 149        @return
 150        TRUE if rectangle is in region.
 151      */
 152     BOOL ContainsRect(const PRect & rect) const;
 153
 154    /**Determine if any part of the rectangle overlapps any part of the region.
 155
 156        @return
 157        TRUE if rectangle intersect region.
 158      */
 159     BOOL OverlapsRect(const PRect & rect) const;
 160
 161    /**Determine if the region is empty.
 162
 163        @return
 164        TRUE if region encloses no space.
 165      */
 166     BOOL IsEmpty() const;
 167
 168    /**Move the region the specified delta amount. The shape of the region does
 169     not change, only its origin.
 170      */
 171     void Offset(
 172       PORDINATE dx,   /// Amount to move region horizontally.
 173       PORDINATE dy    /// Amount ot move region vertically.
 174     );
 175
 176    /**Calculate the smallest enclosing bounding box around the region.
 177
 178        @return
 179        rectangle that encloses the region.
 180      */
 181     PRect GetBounds() const;
 182
 183    /**Calculate the region that is the intersection of the object and the
 184        specified region.
 185
 186        @return
 187        region that is inside both regions.
 188      */
 189     PRegion Intersection(const PRegion & rgn) const;
 190
 191    /**Calcaulte the region that is the union of the object and the specified
 192        region.
 193
 194        @return
 195        region that is inside either region.
 196      */
 197     PRegion Union(const PRegion & rgn) const;
 198
 199
 200 // Include platform dependent part of class
 201 #include <pwlib/region.h>
 202 };
 203
 204
 205 // End Of File ///////////////////////////////////////////////////////////////