Sub Mandelbrot()
    Dim colour(256, 256) As Long
    Dim Row As Long, Col As Long
    Dim xcenter As Long, ycenter As Long, span  As Long, imax  As Long
    Dim startx  As Double, starty As Double, endx  As Double, endy As Double
    Dim Delta As Double
    Dim cx As Double, cy As Double, x As Double, y As Double, xtemp As Double
    Dim i As Long, Colmax As Long, Colscale As Double
    
    'Formata a ?rea de c?lulas
    Columns("A:IV").Select
    Selection.ColumnWidth = 0.2
    Rows("1:257").Select
    Selection.RowHeight = 2
    Range(Cells(1, 1), Cells(256, 256)).Interior.Color = RGB(0, 255, 255)
    Range("a1").Select
    
    
    'Atribui o cenntro da figura
    xcenter = 0
    ycenter = 0
    ' Le a escala e a resolu??o da figura
    span = Range("IX260")
    imax = Range("IX261")
    
    'Definime o limite inicial e final de cada dimens?o
    startx = xcenter - span / 2
    endx = xcenter + span / 2
    starty = ycenter - span / 2
    endy = ycenter + span / 2
    Delta = span / 256
    
   
    'Calcula para cada c?lula a itera??o de Mandelbrot at? a resolu??o definida em imax
    For Row = 1 To 256
        For Col = 1 To 256
            cx = startx + Delta * Col
            cy = starty + Delta * Row
            x = cx
            y = cy
            i = 0
            While i < imax And (x * x + y * y <= 4)
                xtemp = x * x - y * y + cx
                y = 2 * x * y + cy
                x = xtemp
                i = i + 1
            Wend
            colour(Row, Col) = IIf(i = imax, 0, i)
            DoEvents
        Next Col
    Next Row
    
    
    'Descolbre o valor m?ximo associado (o m?nimo ? zero)
    Colmax = 0
    For Row = 1 To 256
        For Col = 1 To 256
            If Colmax < colour(Row, Col) Then Colmax = colour(Row, Col)
        Next
    Next
    
    'Se todos o svalores forem zero, deu pau!
    If Colmax = 0 Then Exit Sub
    
    'Ajusta a escala de cores a ser utilizada
    Colscale = RGB(0, 0, 255) / Colmax    ' aqui no cas ser? o verde e o azul
    For Row = 1 To 256
        For Col = 1 To 256
            Cells(Row, Col).Interior.Color = Int(Colscale * colour(Row, Col))
        Next
        DoEvents
    Next
End Sub



Sub Samambaia()
    Dim colour(256, 256) As Long
    
    
    Columns("A:IV").Select
    Selection.ColumnWidth = 0.2
    Rows("1:257").Select
    Selection.RowHeight = 2
    Range(Cells(1, 1), Cells(256, 256)).Interior.Color = RGB(255, 255, 255)
    Range("a1").Select
    

    
    'Read user inputs
    xcenter = 0 'Range("EP259")
    ycenter = 0 'Range("EP260")
    span = Range("IX260")
    imax = Range("IX261")
    
    'Fix the starting and ending co-ordinates
    startx = xcenter - span / 2
    endx = xcenter + span / 2
    starty = ycenter - span / 2
    endy = ycenter + span / 2
    Delta = span / 256
    
   
    'For each cell in the image, run the iteration for the Mandelbrot set
    For Row = 1 To 256
        For Col = 1 To 256
            cx = startx + Delta * Col
            cy = starty + Delta * Row
            x = cx
            y = cy
            i = 0
            While i < imax And (x * x + y * y <= 4)
                xtemp = x * x - y * y - 0.15
                y = 2 * x * y - 0.17
                x = xtemp
                i = i + 1
            Wend
            colour(Row, Col) = IIf(i = imax, 0, i)
            DoEvents
        Next
    Next
    
    Colmax = 0
    
    'Find the max value of the colour, this will be mapped to white and the other colours
    'will be scaled accordingly
    
    For Row = 1 To 256
        For Col = 1 To 256
            If Colmax < colour(Row, Col) Then Colmax = colour(Row, Col)
        Next
    Next
    
    'If its all black, there is nothing to do
    If Colmax = 0 Then Exit Sub
    
    'Set the colour scale and colour the cells accordingly
    Colscale = RGB(255, 255, 255) / Colmax
    For Row = 1 To 256
        For Col = 1 To 256
            Cells(Row, Col).Interior.Color = Int(Colscale * colour(Row, Col))
        Next
        DoEvents
    Next
End Sub