lib/gfxpoly/poly.h

   1 #ifndef __poly_h__
   2 #define __poly_h__
   3
   4 #include <stdint.h>
   5 #include "../q.h"
   6 #include "../types.h"
   7 #include "wind.h"
   8
   9 /* features */
  10 #define SPLAY
  11 #define DONT_REMEMBER_CROSSINGS
  12
  13 typedef enum {EVENT_CROSS, EVENT_END, EVENT_START, EVENT_HORIZONTAL} eventtype_t;
  14 typedef enum {SLOPE_POSITIVE, SLOPE_NEGATIVE} slope_t;
  15
  16 #define INVALID_COORD (0x7fffffff)
  17 typedef struct _point {
  18     int32_t x;
  19     int32_t y;
  20 } point_t;
  21 type_t point_type;
  22
  23 #define SEGNR(s) ((int)((s)?(s)->nr:-1))
  24
  25 typedef struct _gfxpolystroke {
  26     segment_dir_t dir;
  27     edgestyle_t*fs;
  28     int points_size;
  29     int num_points;
  30     point_t*points;
  31     struct _gfxpolystroke*next;
  32 } gfxpolystroke_t;
  33 typedef struct _gfxpoly {
  34     double gridsize;
  35     gfxpolystroke_t*strokes;
  36 } gfxpoly_t;
  37
  38 typedef struct _segment {
  39     point_t a;
  40     point_t b;
  41     point_t delta;
  42     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)
  43     int32_t minx, maxx;
  44
  45     segment_dir_t dir;
  46     edgestyle_t*fs;
  47     edgestyle_t*fs_out;
  48 #ifdef CHECKS
  49     char fs_out_ok;
  50 #endif
  51
  52     int polygon_nr;
  53     windstate_t wind;
  54     ptroff_t nr;
  55
  56 #ifdef SPLAY
  57     struct _segment*parent;
  58     struct _segment*leftchild;
  59     struct _segment*rightchild;
  60 #endif
  61     struct _segment*left;
  62     struct _segment*right;
  63     char changed;
  64
  65     point_t pos;
  66
  67     gfxpolystroke_t*stroke;
  68     int stroke_pos;
  69
  70 #ifndef DONT_REMEMBER_CROSSINGS
  71     dict_t scheduled_crossings;
  72 #endif
  73 } segment_t;
  74
  75 typedef struct _moments {
  76     double area;
  77     double m[3][3];
  78 } moments_t;
  79
  80 #define LINE_EQ(p,s) ((double)(s)->delta.y*(p).x - (double)(s)->delta.x*(p).y - (s)->k)
  81
  82 /* x1 + ((x2-x1)*(y-y1)) / dy =
  83    (x1*(y2-y1) + (x2-x1)*(y-y1)) / dy =
  84    (x1*(y2-y)  +  x2    *(y-y1)) / dy =
  85    (x1*y2 - x2*y1 + x2*y - y*x1) / dy =
  86    (k + x2*y - x1*y) / dy
  87    (k + dx*y) / dy
  88 */
  89 //#define XPOS(s,ypos) ((s)->a.x + ((s)->delta.x * (double)((ypos) - (s)->a.y)) / (s)->delta.y)
  90 #define XPOS(s,ypos) (((s)->k + (double)(s)->delta.x*ypos) / (s)->delta.y)
  91
  92 #define XPOS_INT(s,ypos) ((int)ceil(XPOS((s),ypos)))
  93 #define XDIFF(s1,s2,ypos) (((s1)->k + (double)(s1)->delta.x*ypos)*(s2)->delta.y - \
  94                            ((s2)->k + (double)(s2)->delta.x*ypos)*(s1)->delta.y)
  95
  96 void gfxpoly_fail(char*expr, char*file, int line, const char*function);
  97
  98 char gfxpoly_check(gfxpoly_t*poly, char updown);
  99 int gfxpoly_num_segments(gfxpoly_t*poly);
 100 int gfxpoly_size(gfxpoly_t*poly);
 101 void gfxpoly_dump(gfxpoly_t*poly);
 102 void gfxpoly_save(gfxpoly_t*poly, const char*filename);
 103 void gfxpoly_save_arrows(gfxpoly_t*poly, const char*filename);
 104 gfxpoly_t* gfxpoly_process(gfxpoly_t*poly1, gfxpoly_t*poly2, windrule_t*windrule, windcontext_t*context, moments_t*moments);
 105
 106 gfxpoly_t* gfxpoly_intersect(gfxpoly_t*p1, gfxpoly_t*p2);
 107 gfxpoly_t* gfxpoly_union(gfxpoly_t*p1, gfxpoly_t*p2);
 108 double gfxpoly_area(gfxpoly_t*p);
 109 double gfxpoly_intersection_area(gfxpoly_t*p1, gfxpoly_t*p2);
 110
 111 #ifndef CHECKS
 112 #ifdef assert
 113 #undef assert
 114 #endif
 115 #define assert(x)
 116 #else
 117 #define assert(x) ((x)?0:gfxpoly_fail(__STRING(x), __FILE__, __LINE__, __PRETTY_FUNCTION__))
 118 #endif
 119
 120
 121 #endif