CashFlow, A Visualization Framework for 3D Flow - Studierstube ...

Software Design3.7. DataAccess Nodetable must be equal to the length of the virtual index.Note: The index in the real array is computed by adding offset to the values fromthe look–up table.Attributes used for figure 3.13 are:• offset = 2• length = 6• unique keyadditional attributes:* look–up tableSize of the lookup table is equal to the length of the virtual array.The virtual index is mapped to the real index by using the index stored in the look–up table. See figure 3.13 showing an example for a random virtual array. The offsetattribute is used to suite the virtual array interface.The range of the virtual index is [0..5].Virtual Array & DataAccess MapThe detailed information on the virtual array is encapsulated inside an object calledDataAccess Map. The DataAccess Map is used in the interface of the virtual array.All nodes requesting data, like the DataConsumer nodes, query a DataAccess nodeand receive a DataAccess Map. Based on the information provided by the DataAccessMap the DataConsumer nodes can instantiate the appropriate virtual array iterator andfinally access the data inside the MultiData node. Thus the DataAccess node providesan interface to the data for the DataConsumer node.57