11 typedef enum {DIR_UP, DIR_DOWN} segment_dir_t;
12 typedef enum {EVENT_CROSS, EVENT_END, EVENT_CORNER, EVENT_START, EVENT_HORIZONTAL} eventtype_t;
13 typedef enum {SLOPE_POSITIVE, SLOPE_NEGATIVE} slope_t;
15 typedef struct _point {
20 typedef struct _fillstyle {
24 typedef struct _edge {
32 typedef struct _windstate
39 typedef struct _windrule
41 windstate_t (*start)(int num_polygons);
42 windstate_t (*add)(windstate_t left, fillstyle_t*edge, segment_dir_t dir, int polygon_nr);
43 fillstyle_t* (*diff)(windstate_t*left, windstate_t*right);
46 typedef struct _segment {
50 double k; //k = a.x*b.y-a.y*b.x = delta.y*a.x - delta.x*a.y (=0 for points on the segment)
63 struct _segment*parent;
64 struct _segment*leftchild;
65 struct _segment*rightchild;
68 struct _segment*right;
73 dict_t scheduled_crossings;
76 #define LINE_EQ(p,s) ((double)(s)->delta.y*(p).x - (double)(s)->delta.x*(p).y - (s)->k)
78 /* x1 + ((x2-x1)*(y-y1)) / dy =
79 (x1*(y2-y1) + (x2-x1)*(y-y1)) / dy =
80 (x1*(y2-y) + x2 *(y-y1)) / dy =
81 (x1*y2 - x2*y1 + x2*y - y*x1) / dy =
82 (k + x2*y - x1*y) / dy
85 //#define XPOS(s,ypos) ((s)->a.x + ((s)->delta.x * (double)((ypos) - (s)->a.y)) / (s)->delta.y)
86 #define XPOS(s,ypos) (((s)->k + (double)(s)->delta.x*ypos) / (s)->delta.y)
88 #define XPOS_INT(s,ypos) ((int)ceil(XPOS((s),ypos)))
89 #define XDIFF(s1,s2,ypos) (((s1)->k + (double)(s1)->delta.x*ypos)*(s2)->delta.y - \
90 ((s2)->k + (double)(s2)->delta.x*ypos)*(s1)->delta.y)
92 typedef struct _gfxpoly {
97 void gfxpoly_fail(char*expr, char*file, int line, const char*function);
99 gfxpoly_t* gfxpoly_new(double gridsize);
100 char gfxpoly_check(gfxpoly_t*poly);
101 int gfxpoly_size(gfxpoly_t*poly);
102 void gfxpoly_dump(gfxpoly_t*poly);
103 gfxpoly_t* gfxpoly_save(gfxpoly_t*poly, const char*filename);
104 gfxpoly_t* gfxpoly_process(gfxpoly_t*poly, windrule_t*windrule);
106 typedef struct _event {
119 #define assert(x) ((x)?0:gfxpoly_fail(__STRING(x), __FILE__, __LINE__, __PRETTY_FUNCTION__))