A popular inquiry from AutoCAD users is how to plot a drawing to a raster file (or bitmap/picture). This is often in response to the need to provide a ‘picture’ of the drawing without actually providing the DWG, or perhaps a drawing is to be displayed in a web page.
First is the simple to use (but less control) command called BMPOUT. It creates a Windows Bitmap .BMP file, appropriate for Paintbrush but not ready for a web page. It captures the whole drawing viewport so center your drawing as well as possible before issuing the command. The following procedures can be used to ‘plot’ your drawing to a raster file.
Setup:
- Choose File > Plotter Manager.
- Choose ‘Add-A-Plotter Wizard’.
- Choose Next, then Next again (accepting My Computer).
- Under Manufacturers, choose ‘Raster File Formats’.Under Models, choose ‘Portable Network Graphics PNG’ (details on why below).
- Choose Next until the Finish button becomes available.
Use:
- Issue the Plot Command.
- On the Plot Device Tab, choose the PNG output created.
- Choose the Properties button, and choose the output resolution desired.
- In the lower right corner, specify the path and filename to create.
- Switch to Plot Settings tab, specify the window and complete the plot to file.
Why PNG?
You may wonder why the PNG file was chosen. It is a clean highly compressed format. In comparison, the JPG (JPEG) format is absolutely NOT a desire-able format for representing linework in raster format. While JPEG is fine for photographs, it is a ‘lossy’ compression and will produce noticeable ‘snow’ on line drawings, especially diagonal lines.
The PNG file is your best choice for raster output. It is very compact in size and is a ‘loseless’ compression. It can be displayed by all ‘current’ web browsers as well.