2d occupency grid map from sparse pointcloud

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Is their any ros module which can convert the 2d sparse point cloud generated from visual slam moudle like orb slam2 ros module or openvslm into 2d occupency grid map where the gaps between the relative grids are removed? I found that by projecting the point cloud into 2d or by using octomap server module the point cloud can be converted into 2d occupency grid map, but i sat that they don't close the gaps between relative grids in that 2d occupency grid map.