| 38 |
|
polySnip(const Vert2_list *contour, int u, int v, int w, int n, int *V) |
| 39 |
|
{ |
| 40 |
|
int p; |
| 41 |
< |
double Ax, Ay, Bx, By, Cx, Cy, Px, Py; |
| 41 |
> |
double Ax, Ay, Bx, By, Cx, Cy, Px, Py, cross; |
| 42 |
|
|
| 43 |
|
Ax = contour->v[V[u]].mX; |
| 44 |
|
Ay = contour->v[V[u]].mY; |
| 49 |
|
Cx = contour->v[V[w]].mX; |
| 50 |
|
Cy = contour->v[V[w]].mY; |
| 51 |
|
|
| 52 |
< |
if ( EPSILON > (((Bx-Ax)*(Cy-Ay)) - ((By-Ay)*(Cx-Ax))) ) return false; |
| 52 |
> |
cross = ((Bx - Ax)*(Cy - Ay)) - ((By - Ay)*(Cx - Ax)); |
| 53 |
> |
if (EPSILON > cross) return EPSILON > -cross ? -1 : false; /* Negative if colinear points */ |
| 54 |
|
|
| 55 |
|
for (p=0;p<n;p++) |
| 56 |
|
{ |
| 57 |
< |
if( (p == u) || (p == v) || (p == w) ) continue; |
| 57 |
> |
if( (p == u) | (p == v) | (p == w) ) continue; |
| 58 |
|
Px = contour->v[V[p]].mX; |
| 59 |
|
Py = contour->v[V[p]].mY; |
| 60 |
+ |
if ((Px == Ax && Py == Ay) || (Px == Bx && Py == By) || |
| 61 |
+ |
(Px == Cx && Py == Cy)) continue; /* Handle donuts */ |
| 62 |
|
if (insideTriangle(Ax,Ay,Bx,By,Cx,Cy,Px,Py)) return false; |
| 63 |
|
} |
| 64 |
|
|
| 126 |
|
{ |
| 127 |
|
/* allocate and initialize list of Vertices in polygon */ |
| 128 |
|
|
| 129 |
< |
int nv, m, u, v, w, count; |
| 129 |
> |
int nv, m, u, v, w, count, result; |
| 130 |
|
int *V; |
| 131 |
|
|
| 132 |
|
if ( contour->nv < 3 ) return false; |
| 149 |
|
for(m=0, v=nv-1; nv>2; ) |
| 150 |
|
{ |
| 151 |
|
/* if we loop, it is probably a non-simple polygon */ |
| 152 |
< |
if (0 >= (count--)) |
| 152 |
> |
if (0 >= count--) |
| 153 |
|
{ |
| 154 |
< |
/* Triangulate: ERROR - probable bad polygon! */ |
| 154 |
> |
/* Triangulate: ERROR - probable bad polygon */ |
| 155 |
|
return false; |
| 156 |
|
} |
| 157 |
|
|
| 160 |
|
v = u+1; if (nv <= v) v = 0; /* new v */ |
| 161 |
|
w = v+1; if (nv <= w) w = 0; /* next */ |
| 162 |
|
|
| 163 |
< |
if ( polySnip(contour,u,v,w,nv,V) ) |
| 163 |
> |
result = polySnip(contour, u, v, w, nv, V); |
| 164 |
> |
if (result > 0) /* successfully found a triangle */ |
| 165 |
|
{ |
| 166 |
< |
int a,b,c,s,t; |
| 166 |
> |
int a,b,c; |
| 167 |
|
|
| 168 |
|
/* true names of the vertices */ |
| 169 |
|
a = V[u]; b = V[v]; c = V[w]; |
| 172 |
|
if (!(*cb)(contour, a, b, c)) return false; |
| 173 |
|
|
| 174 |
|
m++; |
| 175 |
+ |
} |
| 176 |
+ |
if (result) /* successfully found a triangle or three consecutive colinear points */ |
| 177 |
+ |
{ |
| 178 |
+ |
int s,t; |
| 179 |
|
|
| 180 |
|
/* remove v from remaining polygon */ |
| 181 |
|
for(s=v,t=v+1;t<nv;s++,t++) V[s] = V[t]; nv--; |
| 182 |
|
|
| 183 |
< |
/* resest error detection counter */ |
| 183 |
> |
/* reset error detection counter */ |
| 184 |
|
count = 2*nv; |
| 185 |
|
} |
| 186 |
|
} |
