Render checkbox for alignment markers

[madworm]

The layer alignment mark cannot be placed on any other layer then "Edge.Cuts", which defeats its purpose.

---

Application: kicad
Version: (2014-05-27 BZR 4891)-product Release build
wxWidgets: Version 2.8.12 (release,Unicode,compiler with C++ ABI 1002,GCC 4.8.1,STL containers,compatible with 2.6)
Platform: Linux 3.11.10-11-desktop x86_64, 64 bit, Little endian, wxGTK
Boost version: 1.54.0
         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

[Nick Østergaard (nickoe)]

I can confirm this in 5135 also. Having the alignment marker only on Edge.Cuts seems strange. I would expect it to be on all layers. I am not sure of some kind of layer manager shoudl be present for the alignment markers also.

[jean-pierre charras (jp-charras)]

I don't understand this report: when something is put on Edge.Cuts, it is on all layers.

[Nick Østergaard (nickoe)]

Hmm, I am not sure if that is correct. When I export to either gerber or PDF it will only plot the marker on the Edge.Cuts layer file. Maybe I am just interpreting the functionality of the alignment marker wrong.

[Lorenzo Marcantonio (l-marcantonio)]

On Mon, Sep 15, 2014 at 07:17:25PM -0000, Nick Østergaard wrote:
> Hmm, I am not sure if that is correct. When I export to either gerber or
> PDF it will only plot the marker on the Edge.Cuts layer file. Maybe I am
> just interpreting the functionality of the alignment marker wrong.

They *should* plot on every layer in the board. Otherwise I broke
something :D

I'll check how it works

--
Lorenzo Marcantonio
Logos Srl

[Chris Gibson (chris-w-gibson)]

Have you unchecked "Exclude PCB edge layer from other layers"?

[Nick Østergaard (nickoe)]

Hhh, yes, indded that I had. So I guess this is not a bug.

[madworm (madworm-de-inkscape)]

This is a bug. The user is prevented from adding alignment marks to a layer of his choice. Yet another case of "we know better than the user". You can place text on any layer you want, so there is no reason not to allow the same for this.

[Chris Gibson (chris-w-gibson)]

I always assumed the purpose of the alignment marks was so that one or more PCB plots (maybe transparencies for photo method) could be accurately aligned with each other.

If that is the case, then I believe the current method is correct. I can't see a reason to want to put one on another layer alone. It doesn't seem to have any purpose.

[madworm (madworm-de-inkscape)]

The layer alignment mark can be used as a local reference point when laying out a board. You don't always want to have it visible, so putting it onto any of the mechanical layers helps with that. If you can only have it on the edge-cuts layer, you have to turn that one off, which you don't want most of the time. Sometimes you even need multiple reference points, so setting the auxiliary origin doesn't help much.

It's all about choice. Just because You can't think of a good reason for such and such, doesn't mean the next user won't find it exactly that very useful, even essential.

[Lorenzo Marcantonio (l-marcantonio)]

On Wed, Sep 17, 2014 at 11:54:31AM -0000, madworm wrote:
> It's all about choice. Just because You can't think of a good reason for
> such and such, doesn't mean the next user won't find it exactly that
> very useful, even essential.

It's useful for planning routes; I use them as 'breadcrumbs' :D

--
Lorenzo Marcantonio
Logos Srl

[Bjorn Blixhavn (l-bjorn)]

This is definitely a bug. I submitted a board with alignment marks (for solder paste stencil) to Eurocircuits, and got the response
"Our engineers found that different data files have been merged. Merged data is NOT suitable for production.
"We need a separate data file for each layer of your PCB.
So it should be possible to place the alignment marks directly in front copper or silkscreen.

[Jeff Young (jeyjey)]

I think the Edge Cuts is the right place for them (since Edge Cuts can be easily set to appear/not appear on all other layers).

For the intended use that seems like enough. They're usually outside the board edges, aren't they? (Or is that too old-school and only true when using mylar? Maybe modern digital processor don't care where they are. Then again modern digital processors probably don't need them at all....)

Anyway, if you're using them for other uses (such as the breadcrumbs mentioned in an earlier comment), then separate visibility control might be nice. A Render checkbox would suffice.

[Nick Østergaard (nickoe)]

If using them as breafcrubs, you night aswell just use the line tool on a non copper layer.

[Dennis Heidner (heidnerd)]

I recognize that this is an old request that has been marked invalid.

However, I also am running up against the similar problem - and allowing the Kicad user to move an alignment target to another layer and use as a breadcrumb has some validity.

Some board manufactures do want the alignment targets, others if you use them for anything inside the board, you've got a problem. But the alignment targets are also useful to place in the working area of a board such that it's easy to identify the exclusion areas for copper. E.g. putting a module like a ESP12 on he board and you don't want copper. By placing the targets on the board, it makes it easy to use the exclusion tool to mark an area that won't have copper.

The targets are already part of the toolset that's built into PCBNEW. The only problem is that the function is assumed to only be used outside of the edge cut and for aligning mask layers. If the property of the target could be selected and moved to a "Margin" layer, that would remove the target from the gerbers, yet leave the breadcrumbs on the board -- which makes it much easier to generate later revisions of the boards.

Presently, you have to open up the .PCB file with a text editor, then replace the "edge.cut" layer with "Margin" by hand.

[Nick Østergaard (nickoe)]

project management moved to gitlab, please voice your suggestions on https://gitlab.com/kicad/code/kicad/-/issues :)