You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
90 lines
2.3 KiB
90 lines
2.3 KiB
#include "pathing.hpp"
|
|
#include "dbc.hpp"
|
|
#include <vector>
|
|
|
|
using std::vector;
|
|
|
|
inline void add_neighbors(PointList &neighbors, Matrix &closed, size_t y, size_t x) {
|
|
size_t h = closed.size();
|
|
size_t w = closed[0].size();
|
|
vector<size_t> rows{y - 1, y, y + 1};
|
|
vector<size_t> cols{x - 1, x, x + 1};
|
|
|
|
for(size_t row : rows) {
|
|
for(size_t col : cols) {
|
|
if((0 <= row && row < h) &&
|
|
(0 <= col && col < w) &&
|
|
closed[row][col] == 0)
|
|
{
|
|
closed[row][col] = 1;
|
|
neighbors.push_back({.x=col, .y=row});
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Used https://github.com/HenrYxZ/dijkstra-map as a reference.
|
|
*/
|
|
void Pathing::compute_paths(Matrix &walls) {
|
|
INVARIANT();
|
|
// Initialize the new array with every pixel at limit distance
|
|
// NOTE: this is normally ones() * limit
|
|
int limit = $limit == 0 ? $height * $width : $limit;
|
|
matrix_assign($paths, limit);
|
|
|
|
Matrix closed = walls;
|
|
PointList starting_pixels;
|
|
PointList open_pixels;
|
|
|
|
// First pass: Add starting pixels and put them in closed
|
|
for(size_t counter = 0; counter < $height * $width; counter++) {
|
|
size_t x = counter % $width; // BUG: is this right?
|
|
size_t y = counter / $width;
|
|
if($input[y][x] == 0) {
|
|
$paths[y][x] = 0;
|
|
closed[y][x] = 1;
|
|
starting_pixels.push_back({.x=x,.y=y});
|
|
}
|
|
}
|
|
|
|
// Second pass: Add border to open
|
|
for(auto sp : starting_pixels) {
|
|
add_neighbors(open_pixels, closed, sp.y, sp.x);
|
|
}
|
|
|
|
// Third pass: Iterate filling in the open list
|
|
int counter = 1; // leave this here so it's available below
|
|
for(; counter < limit && !open_pixels.empty(); ++counter) {
|
|
PointList next_open;
|
|
for(auto sp : open_pixels) {
|
|
$paths[sp.y][sp.x] = counter;
|
|
add_neighbors(next_open, closed, sp.y, sp.x);
|
|
}
|
|
open_pixels = next_open;
|
|
}
|
|
|
|
// Last pass: flood last pixels
|
|
for(auto sp : open_pixels) {
|
|
$paths[sp.y][sp.x] = counter;
|
|
}
|
|
}
|
|
|
|
void Pathing::set_target(const Point &at, int value) {
|
|
$input[at.y][at.x] = 0;
|
|
}
|
|
|
|
void Pathing::clear_target(const Point &at) {
|
|
$input[at.y][at.x] = 1;
|
|
}
|
|
|
|
bool Pathing::INVARIANT() {
|
|
using dbc::check;
|
|
|
|
check($paths.size() == $height, "paths wrong height");
|
|
check($paths[0].size() == $width, "paths wrong width");
|
|
check($input.size() == $height, "input wrong height");
|
|
check($input[0].size() == $width, "input wrong width");
|
|
|
|
return true;
|
|
}
|
|
|