For many years the PC CAD market has been dominated by AutoCAD. AutoDesk do not readily release the DWG format, and CAD systems are generally playing catch up when reading DWG. In order to compensate for this AutoDesk created DXF, a vector language designed to make transferring DXF files easier.

RiscDXF was released 10 years ago as a way of converting DXF files into RiscCAD format and vice versa.

In the last 10 years, both the RiscCAD and DXF formats have undergone changes, and so RiscCAD Professional Release 10 will see a new version of RiscDXF. DXF is, on the face of it, a simple textual language describing the contents of the vector image. However, as modern CAD systems become more complex, the DXF file format has been expanded to try and cope with this. The result is that many CAD systems cannot accurately render DXF files.

On the outside, RiscDXF looks similar to the previous version, in fact, some of the window options are missing, but don't be fooled. RiscDXF is a powerful DXF processor which can convert a multitude of different DXF format files. RiscDXF has been comprehensively overhauled to meet the demands of modern DXF files. RiscDXF imports vector objects it can render, and importantly, ignores others and carries on processing.

RiscDXF can load all variants of DXF file from early versions of AutoCAD up to the very latest versions. One important feature is the ability to scale model space and paper space separately. This ensures that on drawings saved with a drawing border and model space objects, the whole drawing is imported with the border at the correct size and the model sitting inside the drawing border. When a DXF file is converted, RiscDXF will scan the file to ascertain the scale of the file. The user then has the opportunity to accept the recommended ISO scaling factor, or overide this with their own scale.

Font Handling
RiscDXF utilises a font mapping file which details which RISC OS outline fonts are to be mapped to fonts in the DXF file. These DXF fonts will typically be AutoCAD .shx files or Windows TrueType fonts. This allows DXF files to be imported and suitable fonts used in RiscCAD to give a professional display. These fonts are then re-mapped to Windows fonts when the file is converted back to DXF.

Blocks
Blocks are imported as groups within the RiscCAD file. Nested blocks within the DXF file are imported correctly, at the correct scale, insertion point and angle.

Colours, Weights and Styles
RiscCAD will import line weights, line styles and map AutoCAD colours to RISC OS colours where possible.