static void
find_three_point_rectangle (Rectangle *r,
Point points[4],
gint p)
{
Point a = points[p % 4]; /* 0 1 2 3 */
Point b = points[(p + 1) % 4]; /* 1 2 3 0 */
Point c = points[(p + 2) % 4]; /* 2 3 0 1 */
Point d = points[(p + 3) % 4]; /* 3 0 1 2 */
Point i1; /* intersection point */
Point i2; /* intersection point */
Point i3; /* intersection point */
if (intersect_x (b, c, a, &i1) &&
intersect_y (c, d, i1, &i2) &&
intersect_x (d, a, i2, &i3))
add_rectangle (points, r, i3, i3, i1, i1);
if (intersect_y (b, c, a, &i1) &&
intersect_x (c, d, i1, &i2) &&
intersect_y (d, a, i2, &i3))
add_rectangle (points, r, i3, i3, i1, i1);
if (intersect_x (d, c, a, &i1) &&
intersect_y (c, b, i1, &i2) &&
intersect_x (b, a, i2, &i3))
add_rectangle (points, r, i3, i3, i1, i1);
if (intersect_y (d, c, a, &i1) &&
intersect_x (c, b, i1, &i2) &&
intersect_y (b, a, i2, &i3))
add_rectangle (points, r, i3, i3, i1, i1);
}
int ray_trace(int h,int w,double x0, double y0, double k0, int p, double D)
{
int px,py,pp=(p*k0>0?1:-1);
double nx0,ny0,nx1,ny1,nx,ny,d0,d1;
printf("%d %d %.4lf %.4lf %.6lf %d %.4lf\n", h,w,x0,y0,k0,p,D);
if(D<=0) return 0;
if(hmap[h][w]=='X' && x0!=mx && y0!=my && equal(my,k0*(mx-x0)+y0)) {
d0=distance(x0,y0,mx,my);
printf("@@@%.4lf %.4lf\n",D,d0);
if(d0<D || equal(d0,D)) return 1;
else return 0;
}
// printf(">%c %.4lf s:%.7lf\n",hmap[h][w],d0,fabs(my-k0*(mx-x0)-y0));
if(p>0) nx0=floor(x0+1);
else nx0=ceil(x0-1);
if(pp>0) ny1=floor(y0+1);
else ny1=ceil(y0-1);
ny0=intersect_x(x0,y0,k0,nx0); nx1=intersect_y(x0,y0,k0,ny1);
d0=distance(x0,y0,nx0,ny0); d1=distance(x0,y0,nx1,ny1);
// printf("n0: %.4lf %.4lf %.4lf ", nx0, ny0, d0);
// printf("n1: %.4lf %.4lf %.4lf\n", nx1, ny1,d1);
if(equal(d0,d1)) {
if(hmap[h+p][w+pp]=='#') {
if(hmap[h+p][w]=='#' && hmap[h][w+pp]=='#')
return ray_trace(h,w,nx0,ny0,k0,-1*p,D-d0);
else if(hmap[h+p][w]=='#')
return ray_trace(h+p,w,nx0,ny0,ref_x(k0),p,D-d0);
else if(hmap[h][w+pp]=='#')
return ray_trace(h,w+pp,nx0,ny0,ref_y(k0),-1*p,D-d0);
else return 0;
} else return ray_trace(h+p,w+pp,nx0,ny0,k0,p,D-d0);
}
if(d0<d1) {
if(hmap[h+p][w]=='#')
return ray_trace(h,w,nx0,ny0,ref_x(k0),p,D-d0);
else return ray_trace(h+p,w,nx0,ny0,k0,p,D-d0);
} else {
if(hmap[h][w+pp]=='#')
return ray_trace(h,w,nx1,ny1,ref_y(k0),-1*p,D-d1);
else return ray_trace(h,w+pp,nx1,ny1,k0,p,D-d1);
}
}
static void
find_maximum_aspect_rectangle (Rectangle *r,
Point points[4],
gint p)
{
Point a = points[ p % 4]; /* 0 1 2 3 */
Point b = points[(p + 1) % 4]; /* 1 2 3 0 */
Point c = points[(p + 2) % 4]; /* 2 3 0 1 */
Point d = points[(p + 3) % 4]; /* 3 0 1 2 */
Point i1; /* intersection point */
Point i2; /* intersection point */
Point i3; /* intersection point */
if (intersect_x (b, c, a, &i1))
{
i2.x = i1.x + 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (c, d, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
i2.x = i1.x - 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (c, d, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
}
if (intersect_y (b, c, a, &i1))
{
i2.x = i1.x + 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (c, d, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
i2.x = i1.x - 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (c, d, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
}
if (intersect_x (c, d, a, &i1))
{
i2.x = i1.x + 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (b, c, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
i2.x = i1.x - 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (b, c, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
}
if (intersect_y (c, d, a, &i1))
{
i2.x = i1.x + 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (b, c, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
i2.x = i1.x - 1.0 * r->aspect;
i2.y = i1.y + 1.0;
if (intersect (d, a, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (a, b, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
if (intersect (b, c, i1, i2, &i3))
add_rectangle (points, r, i1, i3, i1, i3);
}
}