Most of the queries we receive about data transfer between AutoCAD and gCADPlus involve a desire to take AutoCAD files and bring them into gCADPlus to use as a base plan. Here we offer some suggestions on converting AutoCAD dwg drawings to gCADPlus.
Tip: Occasionally, we get a request to go the other way. For example, you may be working with an architect who wants to place one of your landscape design drawings in AutoCAD, so we include some advice on that as well.
About AutoCAD and its dwg file format
AutoCAD has been around for a very long time. A new version is released each year, and the file format used by AutoCAD (dwg) changes. That means someone using (say) AutoCAD 2010 cannot open a drawing from a designer using AutoCAD 2019. This regular change to dwg is possibly motivated by Autodesk’s wish to sell more AutoCAD licences, but it does create difficulties.
Tip: If you request a drawing from an architect to be used by you as a base plan, it is a good idea to determine what version of AutoCAD they are using. It is also worth asking them to save a dwg file in an earlier format – maybe 2-3 steps back from the latest AutoCAD. Sometimes extra drawings are attached to dwg file. These are called external references. Ask the sender to ensure they bind external references to the file before sending it to you. (Ref to the BIND command)
gCADPlus file format
The file format used by gCADPlus is lcd. It is a compressed format, which is why gCADPlus files are often much smaller and load faster than AutoCAD files. AutoCAD dwg files will not load directly into AutoCAD, but we can convert them using an exchange format called DXF.
There are two versions of the DXF implementation – ASCII and Binary.
The ASCII DXF file format is a complete representation of an AutoCAD drawing in ASCII text form, which is easily processed by other programs. In addition, a binary form of the full DXF file can also accept limited input in another binary file format.
The binary file contains all the information in an ASCII DXF file but in a more compact form that takes about 25 per cent less file space. It can be read and written more quickly (typically five times faster) by AutoCAD and other CAD applications such as gCADPlus. Unlike ASCII DXF files, which entail a trade-off between size and floating-point accuracy, binary DXF files preserve the accuracy in the drawing database.
How to convert dwg to DXF ready for gCADPlus
To do this, we use a free tool called ODA File Converter published by the Open Design Alliance. This tool takes the dwg file and converts it to DXF, which we can then read in gCADPlus. The figure below shows a screen grab of the OCAD File Converter application in operation.
This movie shows the ODA File Converter in use. We emphasise the need to set input and export criteria in the ODA tool and process a complex AutoCAD drawing in dwg format to a binary DXF ready for gCADPlus.
Here is an example of a file conversion – a dwg file from a survey firm now in gCADPlus.
Talking back to architects and others using DXF exchange
The safest way to send gCADPlus information to an AutoCAD user is also via DXF. Every version of AutoCAD can open a DXF file, so there is no need to worry about the AutoCAD version the recipient of the file is using.
Simply load your drawing in gCADPlus, select File > DXF Tools >, and choose DXFout. A copy of the drawing is produced with the same name that you have been working with, but with the extension .dxf, and that will be able to be read by AutoCAD users.
It’s a good idea to check your conversion before sending
Autodesk provides a free application called DWG TrueView that can test your conversion before sending the file off to your architect. Any AutoCAD version will load a DXF file, but if the architects require a dwg file, check with them, determine their AutoCAD version, and save it from TrueView to DWG in that particular format.
An image shows a DXF file exported from gCADPlus in the TrueView environment. Once the DXF has been shown to load correctly in TrueView, after establishing the version of AutoCAD your architect uses, you can send your dwg drawing to the recipient.
Visit the gCADPlus download page.