void zeroSlope(Point start, Point end, Points &points) const {
if ((start.x - end.x)==0) {
bool isBottomTop = start.y < end.y;
if (!isBottomTop) {
Point tmp = start;
start = end;
end = tmp;
}
double yStart = ceil(start.y);
double yEnd = end.y;
for (double y = yStart; y < yEnd; y += step_)
points.push_back(Point(start.x, y));
if (isBottomTop)
std::sort(points.begin(), points.end(), sort_y());
else
std::sort(points.begin(), points.end(), sort_reverse_y());
} else {
bool isLeftRight = start.x < end.x;
if (!isLeftRight) {
Point tmp = start;
start = end;
end = tmp;
}
double xStart = ceil(start.x);
double xEnd = end.x;
for (double x = xStart; x < xEnd; x += step_)
points.push_back(Point(x, start.y));
if (isLeftRight)
std::sort(points.begin(), points.end(), sort_x());
else
std::sort(points.begin(), points.end(), sort_reverse_x());
}
}
//Builds a y-dimension BST from the sub array ps_[start,end)
node* build_ytree(point* ps_, int start, int end){
printf("Building ytree from %d to %d\n", start, end);
int i;
int len;
int l = end-start;
point* ps = malloc((l)*sizeof(point));
memcpy(ps, &ps_[start], (l)*sizeof(point));
//len is just l rounded up to the next power of 2
if ((l & (l-1)) != 0) {
len = 1<<((8*sizeof(int))-__builtin_clz(l));
} else {
len = l;
}
printf("len=%d, l=%d\n",len,l);
node** nodes = malloc(len*sizeof(node*));
int* indices = malloc(len*sizeof(int));
node* new_node;
sort_y(ps, l);
for (i=0; i<l; i++){
nodes[i] = malloc(sizeof(node));
nodes[i]->l = NULL;
nodes[i]->r = NULL;
nodes[i]->pivot = ps[i];
nodes[i]->leaves = 1;
indices[i] = i;
}
for (;i<len;i++){
nodes[i] = malloc(sizeof(node));
nodes[i]->l = NULL;
nodes[i]->r = NULL;
nodes[i]->pivot.x = HUGE_VAL;
nodes[i]->pivot.y = HUGE_VAL;
nodes[i]->leaves = 0;
indices[i] = i;
}
while (len>0){
//printf("%d\n", len);
len = len>>1;
for (i=0; i<len; i++){
new_node = malloc(sizeof(node));
nodes[2*i]->parent = new_node;
nodes[2*i+1]->parent = new_node;
new_node->l = nodes[2*i];
new_node->r = nodes[2*i+1];
new_node->d = NULL;
new_node->leaves = new_node->l->leaves + new_node->r->leaves;
new_node->pivot = ps[(indices[2*i]+indices[2*i+1])/2];
//printf("len=%d, i=%d, indices[]...=%d\n", len, i, (indices[2*i]+indices[2*i+1])/2);
indices[i] = (indices[2*i]+indices[2*i+1])/2;
nodes[i] = new_node;
}
}
free(indices);
return nodes[0];
}
