CC Circle API

function drawCircle( centerX, centerY, radius, col, solid )
    solid = solid or false
    local isAdvanced = term.isColor and term.isColor()
    local char = isAdvanced and " " or "|"
    if isAdvanced then term.setBackgroundColor( col ) end
    local radStep = 1/(1.5*radius)
    for angle = 1, math.pi+radStep, radStep do
        local pX = math.cos( angle ) * radius * 1.5
        local pY = math.sin( angle ) * radius
        if solid then
            local chord = math.abs(pX)
            term.setCursorPos( centerX - chord/2, centerY - pY )
            write( char:rep( chord ) )
            term.setCursorPos( centerX - chord/2, centerY + pY )
            write( char:rep( chord ) )
        else
            for i=-1,1,2 do
                for j=-1,1,2 do
                    term.setCursorPos( centerX + i*pX, centerY + j*pY )
                    write( char )
                end
            end
        end
    end
end