DXFLIB Reads too many Items.

If you are having problems with dxflib, post here. Please report bugs here.

Moderator: andrew

Post Reply
beding
Newbie Member
Posts: 5
Joined: Mon Nov 08, 2010 12:53 pm

DXFLIB Reads too many Items.

Post by beding » Sun Nov 14, 2010 4:15 pm

When I read some DXF files, e.g. created by ACAD, i seem much more objects than shown.
I expect some objects are stored but no longer in use, how can i see that?

User avatar
andrew
Site Admin
Posts: 5453
Joined: Fri Mar 30, 2007 6:07 am

Post by andrew » Sun Nov 14, 2010 6:35 pm

Most likely you are reading in and displaying all block definitions that are stored in the file. A "block definition" is a named, reusable group. A "block insert" is an entity that references a block definition in a drawing. A drawing might for example contain a block definition called "screw" which contains some lines and other entities that represent a screw. A block insert might exist at position 50,50 which means that your drawing will display a screw at this position. Other block inserts might exist in other positions, reusing the same block definition.

In DXF, every entity is part of a block definition. 'Normal' entities are part of the special block definition named "*Model_Space" which contains the entire drawing and is usually displayed when opening a drawing. Entities that are part of any other block definition are only displayed if block inserts exist for that block definition.

dxflib will call DL_CreationAdapter::addBlock() and DL_CreationAdapter::endBlock() to encapsulate each individual block definition.

If you are not interested in block definitions (or block inserts) at all, simply ignore everything that is not directly part of the special block definition called "*Model_Space". In other words, ignore any DL_CreationAdapter::add*() calls that occur between DL_CreationAdapter::addBlock() and DL_CreationAdapter::endBlock() if the block name is not "*ModelSpace".

beding
Newbie Member
Posts: 5
Joined: Mon Nov 08, 2010 12:53 pm

Post by beding » Sun Nov 14, 2010 7:17 pm

Thanks, that works!

Post Reply

Return to “dxflib Troubleshooting and Problems”