Altium PCB import loses soldermask relief of regions
Description
In Altium it is possible to set a copper region to also create an opening in the soldermask on the layer above it. This is often used for RF designs to remove the soldermask from traces or resonant structures (because the soldermask is an uncontrolled dielectric) or to make land patterns for machined shields.
When imported to kicad, these regions become polygons on Top copper layer but lose their soldermask opening. Since kicad polygons can only exist on one layer, the import should create another polygon on the silkscreen layer in addition to the copper layer.
In Altium:
The region on the right is on Top copper layer but has solder mask expansion set
In kicad:
Steps to reproduce
- From pcbnew, file -> import -> Non-KiCad Board File to import altium2kicad_region_soldermask_expansion.PcbDoc
This file was made with Altium Designer 22.11.1
KiCad Version
Application: KiCad PCB Editor x64 on x64
Version: (7.0.0-rc2-176-g26b9d2f5ac), release build
Libraries:
wxWidgets 3.2.1
FreeType 2.12.1
HarfBuzz 5.0.1
FontConfig 2.14.1
libcurl/7.83.1-DEV Schannel zlib/1.2.13
Platform: Windows 10 (build 19044), 64-bit edition, 64 bit, Little endian, wxMSW
Build Info:
Date: Feb 2 2023 06:17:44
wxWidgets: 3.2.1 (wchar_t,wx containers)
Boost: 1.80.0
OCC: 7.6.2
Curl: 7.83.1-DEV
ngspice: 38
Compiler: Visual C++ 1934 without C++ ABI
Build settings:
KICAD_SPICE=ON
Edited by Brendan Haines