274X supports polygon shapes

On 3/1/2019 2:45, Chris Gantenbein wrote:

Eagle’s 274X output is vector based.  274X supports polygon shapes (outlines) filled solid as a copper pour.  Eagle’s 274X is not utilizing this available option causing huge files.

Is there a way to remedy?

I have been looking into this, but never got to the end of it. I have

this gerber ULP that I made years ago and really wanted to check if I

could use polygon fill to both get rid of the fixed wire fill overlap

issue (causing rounding issues at certain precision) and to get the

filesize down. I gave it up at the time, but I still think it is doable.

I think (not confirmed) that Cadsoft/Autodesk stays away from it because

there may be both gerber viewers and routing gear out there that can't

handle it correctly/consistent, but I still think it should be an option

in the DRC Layers setup. It would make Eagle draw fills much faster on

screen too.

Gerber X2 may be a better target for this function, as you don't have to

support older gear and software.

We are very aware of how line width affects the database. However, we need to use a particular min. line width to achieve ground fill around dense via locations. This is a large 26 layer board with multiple ground layers (single stripline stackup). Consequently, fab processing time and effort is becoming inordinate trying to handle the 200M+ vectorized Gerbers. The question I posed actually came from our fab suggesting a way to solve this problem.

Searching. Is there a run Gerber command line option with parameters/flags we could set differently from the default mode in order to help our situation, such as mentioned above, turning on polygon fill? Or, other command line options that might help?

We are very aware of how line width affects the database. However, we need to use a particular min. line width to achieve ground fill around dense via locations. This is a large 26 layer board with multiple ground layers (single stripline stackup). Consequently, fab processing time and effort is becoming inordinate trying to handle the 200M+ vectorized Gerbers. The question I posed actually came from our fab suggesting a way to solve this problem.

Searching. Is there a run Gerber command line option with parameters/flags we could set differently from the default mode in order to help our situation, such as mentioned above, turning on polygon fill? Or, other command line options that might help?

Hi Chris

A few weeks have passed but I would like to add the following to this discussion.

Polygon fill plains need not be done using only one polygon.

For the typical GND plain, first create the  polygon that surrounds the board and has a large wire size that satisfies the detail needed for most of the board.  For your dense via areas, where you require greater detail, you can place another small polygon over that area and give it a small wire size and the same name.

This should result in smaller file sizes but leave you with the task of ensuring you have identified all the dense areas. 

HTH
Warren