//#define DEBUG
#define CHECKS
+#define SPLAY
typedef enum {DIR_UP, DIR_DOWN} segment_dir_t;
typedef enum {EVENT_CROSS, EVENT_END, EVENT_CORNER, EVENT_START, EVENT_HORIZONTAL} eventtype_t;
fillstyle_t* (*diff)(windstate_t*left, windstate_t*right);
} windrule_t;
+#define SEGNR(s) ((s)?(s)->nr:-1)
+
typedef struct _segment {
point_t a;
point_t b;
windstate_t wind;
int nr;
+#ifdef SPLAY
+ struct _segment*parent;
+ struct _segment*leftchild;
+ struct _segment*rightchild;
+#endif
struct _segment*left;
struct _segment*right;
char changed;