function isObstacle(vector, brush)

    if brush == nil then
        return IsWall(D3DXVECTOR3(vector.x, 0, vector.z)) or IsWallOfGrass(D3DXVECTOR3(vector.x, 0, vector.z))
    elseif brush == false then
        return IsWall(D3DXVECTOR3(vector.x, 0, vector.z))
    else
        return IsWallOfGrass(D3DXVECTOR3(vector.x, 0, vector.z))
    end

end

function OnDraw()

    local x, y, z = player.x, player.y, player.z
    local radius = 1100
    local quality = 2 * math.pi / 30
    local points = {}
    for theta = 0, 2 * math.pi + quality, quality do
        local c = WorldToScreen(D3DXVECTOR3(x + radius * math.cos(theta), y, z - radius * math.sin(theta)))
        for step = 0, radius, 50 do
            if isObstacle(Vector(x + step * math.cos(theta), y, z - step * math.sin(theta)), false) then
                break
            else
                c = WorldToScreen(D3DXVECTOR3(x + step * math.cos(theta), y, z - step * math.sin(theta)))
            end
        end
        points[#points + 1] = D3DXVECTOR2(c.x, c.y)
    end
    DrawLines2(points, 1, 4294967295)

end