clearing all empty cells for minesweeper (game) code

How can I create something that when I click on one of the zero's all the other zeros appear aswell?

I found some advice from Dough Hull on 24 Feb 2014:

 "I Changed Something Flag" = True
 While "I Changed Something Flag" == True
  "I Changed Something Flag" = FALSE
  Start in upper left corner, sweep from left to right, top to bottom until you hit bottom Right:
      If the current square is empty, and any adjacent square is unknown
        reveal unknown square
        make the "I changed something flag" true
      end
 end
 end

However, I don't completely understand this, is there anyone that might be able to explain it a little further? For example, how do I sweep accross the matrix (from left to right)? And how do I actually make it 'reveal' the unknown square?

[Mollymomo]

Hi, this is two years later, but did you figure it out?

Answer 1

[Geoff Hayes]

The original answer can be found at https://www.mathworks.com/matlabcentral/answers/118873-clearing-all-empty-cells-for-minesweeper-game-code but I think that the idea was to keep sweeping over every cell in the matrix until no new cell has been revealed....because every time that you reveal a 0, then you would need to check all neighbouring zeros to ensure that they have been revealed too. And since that new reveal might affect a cell (in a previous column or row) that should be revealed, then a new sweep must be started. If we assume we have two identically sized matrices with one representing the zeros and ones (gamingMatrix), and the other representing whether an cell has been revealed (revealedMatrix) then the sample code might look like

hasRevealedElement = true;
while hasRevealedElement
    hasRevealedElement = false;
    for col=1:size(gamingArea,2)
        for row=1:size(gamingArea,1)
            if gamingArea(row,col) == 0 && revealedMatrix(row,col) == true
                if revealEmptyAdjacentNeighbours(row,col)
                    hasRevealedElement = true;
                end
            end
        end
    end
end

The function revealEmptyAdjacentNeighbours reveals any empty (0) adjacent neighbours to the current cell. It returns true if at least one adjacent neighbour has been revealed. If a sweep has been made where no new element has been revealed, then we know that all 0's adjacent to the one that was revealed by the user, have been revealed too.

Other approaches could be considered as well: a recursive function could be used to reveal all empty adjacent cells to the current revealed one. The function would then be called for all cells that were just revealed, continuing in this fashion until all appropriate cells have been revealed.