vector<int> grid_index::points_near_segment(Vec2 a, Vec2 b, mesh2d& idxd, int additional_cells) {
/* this function will return points that are nearby a potential segment (NOT present inside mesh2d)
NOTE: we could make this code specific to the use case required, meaning line-point distance, but it's not really necessary and sounds like premature optimization, on top of requiring more filtering (needs the point nearest to pt_a.
*/
vector<int> results;
set<Vec2i> cells;
Vec2i a_i(a * resolution);
Vec2i b_i(b * resolution);
// msgm(a_i, b_i);
// if (a_i != b_i)
{
int x_lo = min(a_i.x, b_i.x)-additional_cells;
int x_hi = max(a_i.x, b_i.x)+additional_cells;
int y_lo = min(a_i.y, b_i.y)-additional_cells;
int y_hi = max(a_i.y, b_i.y)+additional_cells;
for (int x = x_lo; x <= x_hi; ++x) {
for (int y = y_lo; y <= y_hi; ++y) {
if(x>-1 && y>-1 && x<resolution && y<resolution){
cells.insert({x,y});
}
}
}
}
// else {
// cells.insert(a_i);
// }
// msg(cells);
set<int> already;
for (auto&cell : cells) {
// auto range = bucket_segments.equal_range(cell);
auto range = bucket_points.equal_range(cell);
for (auto it = range.first; it != range.second; ++it) {
// if (already.count(it->second)) {msgm("skipping,",it->second); continue;}
if (already.count(it->second)) {continue;}
// msg(it->second);
already.insert(it->second);
results.push_back(it->second);
}
}
return results;
}
long matrix::mul_ijk(const matrix *a, const matrix *b, matrix *r)
{
int width, height;
a->size(&height, &width);
for (int i = 0; i < height; i++) {
iter_row r_i(r, i);
for (int j = 0; j < height; j++) {
iter_row a_i(a, i);
iter_col b_i(b, j);
double n = 0;
for (int k = 0; k < width; k++) {
n += **a_i * **b_i;
a_i++; b_i++;
}
**r_i = n;
r_i++;
}
}
return (long)width * width * height * 2;
}
long matrix::mul_kij(const matrix *a, const matrix *b, matrix *r)
{
int width, height, h_div, h_mod;
a->size(&height, &width);
h_div = height / 16;
h_mod = height % 16;
for (iter_all i(r); *i; i++)
**i = 0;
for (int k = 0; k < width; k++) {
iter_col a_i(a, k);
for (int i = 0; i < height; i++) {
number n = **a_i; a_i++;
iter_row b_i(b, k);
iter_row r_i(r, i);
for (int j = 0; j < h_div; j++) {
(*r_i)[0] += (*b_i)[0] * n;
(*r_i)[1] += (*b_i)[1] * n;
(*r_i)[2] += (*b_i)[2] * n;
(*r_i)[3] += (*b_i)[3] * n;
(*r_i)[4] += (*b_i)[4] * n;
(*r_i)[5] += (*b_i)[5] * n;
(*r_i)[6] += (*b_i)[6] * n;
(*r_i)[7] += (*b_i)[7] * n;
(*r_i)[8] += (*b_i)[8] * n;
(*r_i)[9] += (*b_i)[9] * n;
(*r_i)[10] += (*b_i)[10] * n;
(*r_i)[11] += (*b_i)[11] * n;
(*r_i)[12] += (*b_i)[12] * n;
(*r_i)[13] += (*b_i)[13] * n;
(*r_i)[14] += (*b_i)[14] * n;
(*r_i)[15] += (*b_i)[15] * n;
r_i += 16; b_i += 16;
}
for (int j = 0; j < h_mod; j++) {
**r_i += **b_i * n;
r_i++; b_i++;
}
}
}
return (long)width * width * height * 2;
}
void grid_index::add(Vec2 a, Vec2 b, int i) {
Vec2i a_i(a * resolution);
Vec2i b_i(b * resolution);
// msgm("adding segment", i, "coords", a, b);
if (a_i != b_i) {
int x_lo = min(a_i.x, b_i.x);
int x_hi = max(a_i.x, b_i.x);
int y_lo = min(a_i.y, b_i.y);
int y_hi = max(a_i.y, b_i.y);
for (int x = x_lo; x <= x_hi; ++x) {
for (int y = y_lo; y <= y_hi; ++y) {
bucket_segments.insert({ {x,y},i});
}
}
}
else {
//msgm("adding", i, )
bucket_segments .insert({ a_i,i});
}
}
void add(Vec2 a, Vec2 b, int i) {
Vec2i a_i(a / resolution);
Vec2i b_i(b / resolution);
if (a_i != b_i) {
int x_lo = min(a_i.x, b_i.x);
int x_hi = max(a_i.x, b_i.x);
int y_lo = min(a_i.y, b_i.y);
int y_hi = max(a_i.y, b_i.y);
for (int x = x_lo; x <= x_hi; ++x) {
for (int y = y_lo; y <= y_hi; ++y) {
bucket_index.insert({ {x,y},i });
}
}
}
else {
bucket_index.insert({ a_i,i });
}
if (i == 0) msg("SAY WAT AGAIN");
}
int grid_index::intersects(Vec2 a, Vec2 b, mesh2d& idxd, vector<pair<int,Vec2>> &results) {
set<Vec2i> cells;
Vec2i a_i(a * resolution);
Vec2i b_i(b * resolution);
// msgm(a_i, b_i);
if (a_i != b_i) {
int x_lo = min(a_i.x, b_i.x);
int x_hi = max(a_i.x, b_i.x);
int y_lo = min(a_i.y, b_i.y);
int y_hi = max(a_i.y, b_i.y);
for (int x = x_lo; x <= x_hi; ++x) {
for (int y = y_lo; y <= y_hi; ++y) {
cells.insert({x,y});
}
}
}
else {
cells.insert(a_i);
}
set<int> already;
for (auto&cell : cells) {
// auto range = bucket_index.equal_range(cell);
auto range = bucket_segments.equal_range(cell);
for (auto it = range.first; it != range.second; ++it) {
// if (it->second > -1 || already.count(it->second)) continue;
if (already.count(it->second)) continue;
already.insert(it->second);
// auto segment = idxd[-(it->second)-1];
auto segment = idxd[it->second];
//pair<Vec2, Vec2> segment = idxd[it->second];
Vec2 itsc_pt;
bool inter = ::intersects(a, b, segment.first, segment.second, itsc_pt);
if (inter) {
results.push_back({ it->second, itsc_pt });
}
}
}
return results.size();
}