function _findContiguous()

in slides/asset/common/Array2D.js [1998:2043]

• 29 lines of code
• 29 McCabe index (conditional complexity)

  function _findContiguous(cell, r, c, grid, w, h, contiguous, checked, finder, countDiagonals, group) {
    if (!_hasChecked(checked, r, c)) {
      checked[r] || (checked[r] = []);
      checked[r][c] = true; // Avoid repeat checks

      // No need to check out-of-bounds cells
      if (c > -1 && c < w && r > -1 && r < h) {

        // A truthy return value is a match
        if (finder(cell, r, c, grid)) {

          // Spawn a new group
          if (!group) {
            group = [];

            // Push group into the collection
            contiguous.push(group);
          }

          // Add cell's coordinate to the group
          group.push([r, c]);

          // Direction cache
          var up = r - 1;
          var down = r + 1;
          var left = c - 1;
          var right = c + 1;

          // Orthogonal neighbors
          if (up > -1 && up < h)       _findContiguous(grid[up][c], up, c, grid, w, h, contiguous, checked, finder, countDiagonals, group);
          if (down > -1 && down < h)   _findContiguous(grid[down][c], down, c, grid, w, h, contiguous, checked, finder, countDiagonals, group);
          if (left > -1 && left < w)   _findContiguous(grid[r][left], r, left, grid, w, h, contiguous, checked, finder, countDiagonals, group);
          if (right > -1 && right < w) _findContiguous(grid[r][right], r, right, grid, w, h, contiguous, checked, finder, countDiagonals, group);

          // Diagonal neighbors (if desired)
          if (countDiagonals) {
            if (up > -1 && up < h && left > -1 && left < w)       _findContiguous(grid[up][left], up, left, grid, w, h, contiguous, checked, finder, countDiagonals, group);
            if (up > -1 && up < h && right > -1 && right < w)     _findContiguous(grid[up][right], up, right, grid, w, h, contiguous, checked, finder, countDiagonals, group);
            if (down > -1 && down < h && left > -1 && left < w)   _findContiguous(grid[down][left], down, left, grid, w, h, contiguous, checked, finder, countDiagonals, group);
            if (down > -1 && down < h && right > -1 && right < w) _findContiguous(grid[down][right], down, right, grid, w, h, contiguous, checked, finder, countDiagonals, group);
          }

        } else { /* The cell did not match; skip. */ }
      } else { /* The cell was out-of-bounds; skip. */ }
    } else { /* The cell was already checked; skip. */ }
  }