src/util/box.h

   1 #ifndef EL__UTIL_BOX_H
   2 #define EL__UTIL_BOX_H
   3
   4 /** A rectangular part of a drawing surface, such as the screen.  */
   5 struct box {
   6         int x;
   7         int y;
   8         int width;
   9         int height;
  10 };
  11
  12 /** @relates box */
  13 static inline int
  14 is_in_box(struct box *box, int x, int y)
  15 {
  16         return (x >= box->x && y >= box->y
  17                 && x < box->x + box->width
  18                 && y < box->y + box->height);
  19 }
  20
  21 /** @relates box */
  22 static inline int
  23 row_is_in_box(struct box *box, int y)
  24 {
  25         return (y >= box->y && y < box->y + box->height);
  26 }
  27
  28 /** @relates box */
  29 static inline int
  30 col_is_in_box(struct box *box, int x)
  31 {
  32         return (x >= box->x && x < box->x + box->width);
  33 }
  34
  35 /** Check whether a span of columns is in @a box.
  36  * Mainly intended for use with double-width characters.
  37  * @relates box */
  38 static inline int
  39 colspan_is_in_box(struct box *box, int x, int span)
  40 {
  41         return (x >= box->x && x + span <= box->x + box->width);
  42 }
  43
  44 /** For two intersecting boxes, set boxi to represent the intersect.
  45  * The behavior is kind of undefined for non-intersecting boxes, but
  46  * width and height of boxi are guaranteed to be negative.
  47  * @relates box */
  48 static inline void
  49 box_intersect(struct box *boxi, struct box *box1, struct box *box2)
  50 {
  51         boxi->x = int_max(box1->x, box2->x);
  52         boxi->y = int_max(box1->y, box2->y);
  53         boxi->width  = int_min(box1->x + box1->width,  box2->x + box2->width)  - boxi->x;
  54         boxi->height = int_min(box1->y + box1->height, box2->y + box2->height) - boxi->y;
  55 }
  56
  57
  58 /** @relates box */
  59 static inline void
  60 set_box(struct box *box, int x, int y, int width, int height)
  61 {
  62         box->x = int_max(0, x);
  63         box->y = int_max(0, y);
  64         box->width = int_max(0, width);
  65         box->height = int_max(0, height);
  66 }
  67
  68 /** @relates box */
  69 static inline void
  70 copy_box(struct box *dst, struct box *src)
  71 {
  72         copy_struct(dst, src);
  73 }
  74
  75 #define dbg_show_box(box) DBG("x=%i y=%i width=%i height=%i", (box)->x, (box)->y, (box)->width, (box)->height)
  76 #define dbg_show_xy(x_, y_) DBG("x=%i y=%i", x_, y_)
  77
  78
  79 #endif