AoE4 Generated Map Function: Closest or Furthest edge functions

closestEdgeFurthestEdge.lua

--tells you what is the closest and furthest edge from a given coordinate
--copy and paste code to preview at https://aoe4.app/

--returns the closest edge of a given coordinate
--rowCoordinate (int) grid coordinate
--colCoordinate (int) grid coordinate
--edgesCompare (array) the edges to compare e.g. { 'left', 'right' } what is closest edge, left or right
--returns (string) 'top' 'right' 'bottom' 'left'
function closestEdge(rowCoordinate, colCoordinate, edgesCompare)
    
    if (edgesCompare == nil) then
        edgesCompare = { 'top', 'right', 'bottom', 'left' } 
    end
    
    edges = {}
    edges.top = rowCoordinate
    edges.right = gridSize - colCoordinate + 1
    edges.bottom = gridSize - rowCoordinate + 1
    edges.left = colCoordinate
    
    finalEdges = {}
    for edgeIndex = 1, #edgesCompare do
        edgeName = edgesCompare[edgeIndex]
        edgeVal = edges[edgeName]
        finalEdges[edgeName] = edgeVal
    end
    
    local edgeReturn
    for i, v in pairs(finalEdges) do
        edgeReturn = edgeReturn or i
        if (v < finalEdges[edgeReturn]) then
            edgeReturn = i
        end
    end
    
    return edgeReturn
    
end

--returns the furthest edge of a given coordinate
--rowCoordinate (int) grid coordinate
--colCoordinate (int) grid coordinate
--edgesCompare (array) the edges to compare e.g. { 'left', 'right' } what is furthest edge, left or right
--returns (string) 'top' 'right' 'bottom' 'left'
function furthestEdge(rowCoordinate, colCoordinate, edgesCompare)
    
    if (edgesCompare == nil) then
        edgesCompare = { 'top', 'right', 'bottom', 'left' } 
    end
    
    edges = {}
    edges.top = rowCoordinate
    edges.right = gridSize - colCoordinate + 1
    edges.bottom = gridSize - rowCoordinate + 1
    edges.left = colCoordinate
    
    finalEdges = {}
    for edgeIndex = 1, #edgesCompare do
        edgeName = edgesCompare[edgeIndex]
        edgeVal = edges[edgeName]
        finalEdges[edgeName] = edgeVal
    end
    
    local edgeReturn
    for i, v in pairs(finalEdges) do
        edgeReturn = edgeReturn or i
        if (v > finalEdges[edgeReturn]) then
            edgeReturn = i
        end
    end
    
    return edgeReturn
    
end