Large plot data warning from Cadsoft Eagle CAM processor
Today we got a new warning from Eagle’s CAM processor when exporting gerbers to make PCBs. When the CAM processor started we got the error “Board contains a polygon that may cause extremely large plot data”. After some removing nearly every component from the PCB, we found that it was related to the arrows on the silk shown above. The edges have a sharp angle, and the polygons at the tips have a width of zero. To correct the issue we changed the offending polygons’ width to positive value.
This entry was posted in Eagle and tagged bug, Cadsoft Eagle, error.
Comments
How big would the data have been? Usually I can click “Yes” or “Yes to all” on the warning box and it continues fine. It usually happens if I have a logo on the board, but I’ve never had a board house come back to me and say it’s a problem.
Divide By Zero error being handled?
The CAM processor will balk this warning whenever zero width polygons are involved. Since a polygon is a raster of wires then zero thickness will yield an infinite amount of wires. This is a gross simplification, but it’s the gist of the issue. There’s no such thing a zero apeture but when you setup the polygon width to be zero EAGLE uses a very small width which ends up generating a lot of CAM data.
In extreme cases this can cause the CAM processor to take hours processing a file were it would normally take seconds or minutes to process.
We generally recommend to use the largest width you can get away with, but as long as it’s a non-zero value you’ll be OK.
Best Regards,
Jorge Garcia
Cadsoft Support
P.S Next time you run into problems please give us a call at 954-237-0932 or shoot an e-mail to sales@cadsoftusa.com. I feel bad when users lose time, with a question or issue that can be resolved quickly.
I’m impressed with Cadsoft’s reply on this post. Mr Garcia, thanks for showing that you’re a company that cares about customer service, and proactively searches out ways to assist your users.