In this AutoCAD 2D training course you will learn on how to use look up table, a lookup table is basically a list of window properties which is added to a dynamic block in Autocad 2D. A dynamic block is created within Autocad and consists of blocks which can be adjusted to show variations in length, width, orientation, scale and position. They can also consist of various different objects like bathroom utilities when the block is inserted the user has the choice of which utility they want to be visible in the drawing. The dynamic quality is added by introducing various parameters and actions within the block editor. This functionality was previously part of the AutoLisp programming code until AutoDesk incorporated it into the program itself.
In the example of a dynamic window block with variable lengths the lookup table would consist of a list of window lengths and descriptions. And when you select from the list, the block automatically changes to the selected length.
To create a Lookup Table, open the Block Editor and choose a dynamic window block, for example. On the left hand side of the interface a palette has opened with Parameters and Actions tabs. Choose the Lookup tool from the Parameters list and click in the drawing itself to place the list above the top left corner of the window block. Next open the Actions tab and choose Lookup; then click or double-click on the icon above the block whereupon the Property Lookup Table opens. Click the Add Properties button and OK and a tag Distance 1 appears in a table on the left column. This table is where we enter the data for our lookup table. Click in the field below Distance 1 and type 1000. Next click in the field below Lookup 1 and type (for example) 1000 Superior, Dual Pane.
Repeat the process by clicking in the next field below Distance 1 and type 1500. Click in the next field below Lookup 1 and type 1500, Modern, 9 lights, Timber. Click in next field below Distance 1 and type 2000. Click in the next field below Lookup 1 and type 2000, Aluminium, Budget. Then click on Read Only below Custom and select Allow Reverse Lookup. Hit OK to complete this list. Now save the block on the top left of the panel and Close Block Editor, also choosing to save the changes.
To test the process select the block and notice the lookup button on the top left; click on it to see the list. Then select a length and block should change size accordingly. If it doesn’t change you’ll need to edit the block by going back into the Block Editor and right-clicking on the Lookup icon to open the dialog box again. Choose Display Lookup table and make your changes, then save and close the dialog box. Finally save the file, and the block with its lookup table will be saved with this drawing file. It can later be accessed via the Autocad Design Centre, or through the Import Block command.
Other options for a lookup table would be to specify the width and height of an object. Door types with associated widths would be another example, more information here.