layout/lucca-rect.h

   1 /* Copyright (c) 2008 Vincent Povirk
   2
   3 Permission is hereby granted, free of charge, to any person
   4 obtaining a copy of this software and associated documentation
   5 files (the "Software"), to deal in the Software without
   6 restriction, including without limitation the rights to use,
   7 copy, modify, merge, publish, distribute, sublicense, and/or sell
   8 copies of the Software, and to permit persons to whom the
   9 Software is furnished to do so, subject to the following
  10 conditions:
  11
  12 The above copyright notice and this permission notice shall be
  13 included in all copies or substantial portions of the Software.
  14
  15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  17 OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22 OTHER DEALINGS IN THE SOFTWARE.
  23 */
  24
  25 #ifndef LUCCA_RECT_H
  26 #define LUCCA_RECT_H
  27
  28 #include "lucca-common.h"
  29
  30 /*
  31     Internal rectangle type.
  32     LuccaRect stores LEFT, RIGHT, TOP, BOTTOM coordinates internally and has
  33       operations for manipulating/comparing rectangles without hard-coding
  34       special cases for different orientations.
  35 */
  36
  37 typedef struct {
  38     gint c[4];
  39 } LuccaRect;
  40
  41 /* lucca_rect_from_xywh: Create a rectangle from its xywh coordinates */
  42 static LuccaRect lucca_rect_from_xywh(gint x, gint y, gint width, gint height) {
  43     LuccaRect result = {{x, x+width-1, y, y+height-1}};
  44     return result;
  45 }
  46
  47 /* lucca_rect_getx, lucca_rect_gety, lucca_rect_getwidth, lucca_rect_getheight:
  48     Returns an xywh coordinate of the given rectangle */
  49 static gint lucca_rect_getx(LuccaRect r) {
  50     return r.c[LUCCA_SIDE_LEFT];
  51 }
  52 static gint lucca_rect_gety(LuccaRect r) {
  53     return r.c[LUCCA_SIDE_TOP];
  54 }
  55 static gint lucca_rect_getwidth(LuccaRect r) {
  56     return r.c[LUCCA_SIDE_RIGHT]-r.c[LUCCA_SIDE_LEFT]+1;
  57 }
  58 static gint lucca_rect_getheight(LuccaRect r) {
  59     return r.c[LUCCA_SIDE_BOTTOM]-r.c[LUCCA_SIDE_TOP]+1;
  60 }
  61
  62 /* lucca_rect_contains_point: Test if a rectangle contains a point */
  63 static gboolean lucca_rect_contains_point(LuccaRect r, gint x, gint y) {
  64     return (r.c[LUCCA_SIDE_LEFT] <= x &&
  65             r.c[LUCCA_SIDE_RIGHT] >= x &&
  66             r.c[LUCCA_SIDE_TOP] <= y &&
  67             r.c[LUCCA_SIDE_BOTTOM] >= y);
  68 }
  69
  70 /* lucca_rect_contains_rect: Test if a rectangle contains another rectangle */
  71 static gboolean lucca_rect_contains_rect(LuccaRect a, LuccaRect b) {
  72     return (a.c[LUCCA_SIDE_LEFT] <= b.c[LUCCA_SIDE_LEFT] &&
  73             a.c[LUCCA_SIDE_RIGHT] >= b.c[LUCCA_SIDE_RIGHT] &&
  74             a.c[LUCCA_SIDE_TOP] <= b.c[LUCCA_SIDE_TOP] &&
  75             a.c[LUCCA_SIDE_BOTTOM] >= b.c[LUCCA_SIDE_BOTTOM]);
  76 }
  77
  78 /* lucca_rects_intersect: Test if two rectangles intersect */
  79 static gboolean lucca_rects_intersect(LuccaRect a, LuccaRect b) {
  80     if (a.c[LUCCA_SIDE_LEFT] > b.c[LUCCA_SIDE_RIGHT])
  81         return FALSE;
  82     if (b.c[LUCCA_SIDE_LEFT] > a.c[LUCCA_SIDE_RIGHT])
  83         return FALSE;
  84     if (a.c[LUCCA_SIDE_TOP] > b.c[LUCCA_SIDE_BOTTOM])
  85         return FALSE;
  86     if (b.c[LUCCA_SIDE_TOP] > a.c[LUCCA_SIDE_BOTTOM])
  87         return FALSE;
  88     return TRUE;
  89 }
  90
  91 /* lucca_rect_get_thickness: Return a rectangle's thickness in the given direction */
  92 static guint lucca_rect_get_thickness(LuccaRect r, LuccaSide side) {
  93     return r.c[side|1] - r.c[side&2] + 1;
  94 }
  95
  96 /* lucca_rect_set_thickness: Change rectangle's thickness by changing the given coordinate */
  97 static LuccaRect lucca_rect_set_thickness(LuccaRect r, LuccaSide side, guint thickness) {
  98     r.c[side] = r.c[lucca_side_opposite(side)] + lucca_side_sign(side) * (thickness - 1);
  99     return r;
 100 }
 101
 102 #endif
 103