Pad clearance not visible with OpenGL

[Robin Whittle]

I haven't tried this with the latest nightly, because the machine I have to test that doesn't do OpenGL, due to it being a VM under VirtualBox. So this report is about version 4.0.2:

Application: pcbnew
Version: 4.0.2-stable release build
wxWidgets: Version 3.0.2 (debug,wchar_t,compiler with C++ ABI 1009,GCC 5.2.0,wx containers,compatible with 2.8)
Platform: Windows 7 (build 7601, Service Pack 1), 64-bit edition, 64 bit, Little endian, wxMSW
Boost version: 1.57.0
         USE_WX_GRAPHICS_CONTEXT=OFF
         USE_WX_OVERLAY=OFF
         KICAD_SCRIPTING=ON
         KICAD_SCRIPTING_MODULES=ON
         KICAD_SCRIPTING_WXPYTHON=ON
         USE_FP_LIB_TABLE=HARD_CODED_ON
         BUILD_GITHUB_PLUGIN=ON

With the default canvas I can see a line around pads when I turn on: Preferences > Display > Show pad clearance.

No such things are visible when I do this with the OpenGL canvas or the Cairo canvas (which is very slow).

The closest potentially related bug report I could find is from 2014: https://bugs.launchpad.net/kicad/+bug/1333100 .
See also a report I just made "Solder mask layer not visible with default canvas": https://bugs.launchpad.net/kicad/+bug/1570831 .

Thanks for KiCad!

[Novak Tamas (novak-7)]

It is a similar feature to turn on Preferences - Interactive routing - Mode=Highlite collisions. You see green light when in proximity.
On the other hand if you select "Shove" the clearance will be maintained automatically, no really need to show clearance.

[Rogier Lodewijks (rogier-f)]

Possibly a bit of topic, but IMO the collision highlighting would be of great help when searching/fixing DRC violations. Currently the DRC markers only point you in the general direction of the error. It's up to the user to find out what's wrong exactly. Personally I think the DRC-error highlighting in Eagle is very nice, clearly pointing out the issue. (example: http://i.stack.imgur.com/3ni9Q.png)

[Novak Tamas (novak-7)]

@Rogier I agree. I'd rephrase the wish as not pad clearance should be visible everywhere, but DRC error display should be enhanced with showing clearance area borders, and hilite their collisions.

[Strntydog (strntydog)]

Clearance is a nice thing to see when laying tacks, even though GAL can highlight collisions, you need to then back track until the collision goes away, the "halo" can help a designer see what the clearance is along his entire track, just because there is no collision DOES NOT mean that clearance is optimal for the track.

http://i.imgur.com/2AzG3cy.png <- Shows clearance for the current track (in legacy)
http://i.imgur.com/BSX7jkc.png <- GAL Doesnt.

It doesn't seem like an unreasonable request for a designer to be able to enable the visible clearance lines to a track they are routing on GAL, and I would really like them.