misc/rect.c

   1 /*
   2  * Rectangle-related functions
   3  *
   4  * Copyright 1993 Alexandre Julliard
   5  */
   6
   7 static char Copyright[] = "Copyright  Alexandre Julliard, 1993";
   8
   9 #include "windows.h"
  10
  11 #define MIN(a,b) ((a) < (b) ? (a) : (b))
  12 #define MAX(a,b) ((a) > (b) ? (a) : (b))
  13
  14
  15 /***********************************************************************
  16  *           SetRect    (USER.72)
  17  */
  18 void SetRect( LPRECT rect, short left, short top, short right, short bottom )
  19 {
  20     rect->left   = left;
  21     rect->right  = right;
  22     rect->top    = top;
  23     rect->bottom = bottom;
  24 }
  25
  26
  27 /***********************************************************************
  28  *           SetRectEmpty    (USER.73)
  29  */
  30 void SetRectEmpty( LPRECT rect )
  31 {
  32     rect->left = rect->right = rect->top = rect->bottom = 0;
  33 }
  34
  35
  36 /***********************************************************************
  37  *           CopyRect    (USER.74)
  38  */
  39 void CopyRect( LPRECT dest, LPRECT src )
  40 {
  41     *dest = *src;
  42 }
  43
  44
  45 /***********************************************************************
  46  *           IsRectEmpty    (USER.75)
  47  */
  48 BOOL IsRectEmpty( LPRECT rect )
  49 {
  50     return ((rect->left == rect->right) || (rect->top == rect->bottom));
  51 }
  52
  53
  54 /***********************************************************************
  55  *           PtInRect    (USER.76)
  56  */
  57 BOOL PtInRect( LPRECT rect, POINT pt )
  58 {
  59     return ((pt.x >= rect->left) && (pt.x < rect->right) &&
  60             (pt.y >= rect->top) && (pt.y < rect->bottom));
  61 }
  62
  63
  64 /***********************************************************************
  65  *           OffsetRect    (USER.77)
  66  */
  67 void OffsetRect( LPRECT rect, short x, short y )
  68 {
  69     rect->left   += x;
  70     rect->right  += x;
  71     rect->top    += y;
  72     rect->bottom += y;
  73 }
  74
  75
  76 /***********************************************************************
  77  *           InflateRect    (USER.78)
  78  */
  79 void InflateRect( LPRECT rect, short x, short y )
  80 {
  81     rect->left   -= x;
  82     rect->top    -= y;
  83     rect->right  += x;
  84     rect->bottom += y;
  85 }
  86
  87
  88 /***********************************************************************
  89  *           IntersectRect    (USER.79)
  90  */
  91 BOOL IntersectRect( LPRECT dest, LPRECT src1, LPRECT src2 )
  92 {
  93     if (IsRectEmpty(src1) || IsRectEmpty(src2) ||
  94         (src1->left >= src2->right) || (src2->left >= src1->right) ||
  95         (src1->top >= src2->bottom) || (src2->top >= src1->bottom))
  96     {
  97         SetRectEmpty( dest );
  98         return FALSE;
  99     }
 100     dest->left   = MAX( src1->left, src2->left );
 101     dest->right  = MIN( src1->right, src2->right );
 102     dest->top    = MAX( src1->top, src2->top );
 103     dest->bottom = MIN( src1->bottom, src2->bottom );
 104     return TRUE;
 105 }
 106
 107
 108 /***********************************************************************
 109  *           UnionRect    (USER.80)
 110  */
 111 BOOL UnionRect( LPRECT dest, LPRECT src1, LPRECT src2 )
 112 {
 113     if (IsRectEmpty(src1))
 114     {
 115         if (IsRectEmpty(src2))
 116         {
 117             SetRectEmpty( dest );
 118             return FALSE;
 119         }
 120         else *dest = *src2;
 121     }
 122     else
 123     {
 124         if (IsRectEmpty(src2)) *dest = *src1;
 125         else
 126         {
 127             dest->left   = MIN( src1->left, src2->left );
 128             dest->right  = MAX( src1->right, src2->right );
 129             dest->top    = MIN( src1->top, src2->top );
 130             dest->bottom = MAX( src1->bottom, src2->bottom );
 131         }
 132     }
 133     return TRUE;
 134 }
 135
 136
 137 /***********************************************************************
 138  *           EqualRect    (USER.244)
 139  */
 140 BOOL EqualRect( LPRECT rect1, LPRECT rect2 )
 141 {
 142     return ((rect1->left == rect2->left) && (rect1->right == rect2->right) &&
 143             (rect1->top == rect2->top) && (rect1->bottom == rect2->bottom));
 144 }
 145
 146
 147 /***********************************************************************
 148  *           SubtractRect    (USER.373)
 149  */
 150 BOOL SubtractRect( LPRECT dest, LPRECT src1, LPRECT src2 )
 151 {
 152     RECT tmp;
 153
 154     if (IsRectEmpty( src1 ))
 155     {
 156         SetRectEmpty( dest );
 157         return FALSE;
 158     }
 159     *dest = *src1;
 160     if (IntersectRect( &tmp, src1, src2 ))
 161     {
 162         if (EqualRect( &tmp, dest ))
 163         {
 164             SetRectEmpty( dest );
 165             return FALSE;
 166         }
 167         if ((tmp.top == dest->top) && (tmp.bottom == dest->bottom))
 168         {
 169             if (tmp.left == dest->left) dest->left = tmp.right;
 170             else if (tmp.right == dest->right) dest->right = tmp.left;
 171         }
 172         else if ((tmp.left == dest->left) && (tmp.right == dest->right))
 173         {
 174             if (tmp.top == dest->top) dest->top = tmp.bottom;
 175             else if (tmp.bottom == dest->bottom) dest->bottom = tmp.top;
 176         }
 177     }
 178     return TRUE;
 179 }
 180