10 typedef enum {DIR_UP, DIR_DOWN} segment_dir_t;
11 typedef enum {EVENT_CROSS, EVENT_END, EVENT_CORNER, EVENT_START, EVENT_HORIZONTAL} eventtype_t;
12 typedef enum {SLOPE_POSITIVE, SLOPE_NEGATIVE} slope_t;
14 typedef struct _point {
19 typedef struct _fillstyle {
23 typedef struct _edge {
31 typedef struct _windstate
38 typedef struct _windrule
40 windstate_t (*start)(int num_polygons);
41 windstate_t (*add)(windstate_t left, fillstyle_t*edge, segment_dir_t dir, int polygon_nr);
42 fillstyle_t* (*diff)(windstate_t*left, windstate_t*right);
45 typedef struct _segment {
49 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)
62 struct _segment*right;
67 dict_t scheduled_crossings;
70 #define LINE_EQ(p,s) ((double)(s)->delta.y*(p).x - (double)(s)->delta.x*(p).y - (s)->k)
72 /* x1 + ((x2-x1)*(y-y1)) / dy =
73 (x1*(y2-y1) + (x2-x1)*(y-y1)) / dy =
74 (x1*(y2-y) + x2 *(y-y1)) / dy =
75 (x1*y2 - x2*y1 + x2*y - y*x1) / dy =
76 (k + x2*y - x1*y) / dy
79 //#define XPOS(s,ypos) ((s)->a.x + ((s)->delta.x * (double)((ypos) - (s)->a.y)) / (s)->delta.y)
80 #define XPOS(s,ypos) (((s)->k + (double)(s)->delta.x*ypos) / (s)->delta.y)
82 #define XPOS_INT(s,ypos) ((int)ceil(XPOS((s),ypos)))
83 #define XDIFF(s1,s2,ypos) (((s1)->k + (double)(s1)->delta.x*ypos)*(s2)->delta.y - \
84 ((s2)->k + (double)(s1)->delta.x*ypos)*(s1)->delta.y)
86 // rewrite as XDIFF==0?
87 #define XPOS_EQ(s1,s2,ypos) (XPOS((s1),(ypos))==XPOS((s2),(ypos)))
89 typedef struct _gfxpoly {
94 void gfxpoly_fail(char*expr, char*file, int line, const char*function);
96 gfxpoly_t* gfxpoly_new(double gridsize);
97 char gfxpoly_check(gfxpoly_t*poly);
98 int gfxpoly_size(gfxpoly_t*poly);
99 void gfxpoly_dump(gfxpoly_t*poly);
100 gfxpoly_t* gfxpoly_save(gfxpoly_t*poly, const char*filename);
101 gfxpoly_t* gfxpoly_process(gfxpoly_t*poly, windrule_t*windrule);
103 typedef struct _event {
116 #define assert(x) ((x)?0:gfxpoly_fail(__STRING(x), __FILE__, __LINE__, __PRETTY_FUNCTION__))