TPC stores its blocks using the DXF (Data eXchange Format) format used to exchange data with CAD programs. Each block file starts with a BLOCK command and ends with an ENDBLK command. The DXF format allows TPC to re-use blocks you may be currently using in another CAD program and share its blocks with other programs.
The following example is the 'Set Rebar' block.
Notice that the block name (Set_Rebar) uses an underscore instead of a space. Within TPC, this block will be identified as 'Set Rebar'. TPC replaces the underscore with a space for internal use, but writes the underscore to the block file to maintain compatibility with AutoCAD.
You may also notice that TPC includes an '80' attribute with both the block and the CIRCLE entity. TPC stores information about the block and its entities in these values. TPC does not include these attributes in the BLOCK definitions when it writes a drawing to a DXF file. This ensures compatibility with CAD programs that may not allow this attribute.
Editing a Block Reference
Using Blocks from Other CAD Programs
Storing Blocks in the Drawing
Converting Blocks to Groups
Grouping Drawing Objects
No CAD Zone Drawings
Using Drawing View
Smart Drawing Objects
Working with Drawing Objects
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