Item 1.
That is a very important point that I haven’t commented on until now. I agree that it is better to keep the text editable.
One of the workflows suggested in this thread involves Path > Object to Path. If you do this on the original text in your Inkscape file, then the text is no longer editable as text. (The text, once converted to paths, can be edited by having graphical effects applied to it. This is necessary sometimes, which is one reason the Object to Path menu item exists, aside from situations where an Inkscape file is to be used by something that can handle paths better than text.) In my business-card example, if the makerspace changes its hours or e-mail address, then it is much easier to update the business-card design if the text is still text than if all the text were converted to paths.
In the legal realm of software licensing, “source code” is defined as (to my recollection) “the preferred form for modification.” If you change your original text into paths, then you would be removing the source code for that text from your own design. Having the text-to-path or text-to-raster conversion be done by some means that makes a copy, preserves the source code for you.
Item 2.
Manually resizing one layer (the bitmap in this suggestion) to match another layer (the vector cuts) is exactly what we at our makerspace are trying to avoid.
When we were manually resizing in GFUI, we would get artifacts like, a ridge of non-engraved material inside of the cut line, because the engraved rectangle didn’t quite line up with the rectangle of cut. Then this ridge has to be trimmed off by hand.
With the rasterize
filter, no resizing is needed. The raster output from Inkscape always registers perfectly with the vector lines on the other layers.
Item 3.
Some general points:
Techniques that use one layer to generate another layer that looks the same, can lead to mistakes in which you leave the wrong layer visible when sending the design to the laser cutter.
Also, you need to generate that output layer all over again whenever you make any change, no matter how minor, to its source layer. With the rasterize
-filter approach, any change that doesn’t add any top-level objects to the set of rasterized objects doesn’t require you to do that generating step at all - Inkscape automatically updates the raster data in the next PDF that you export. (“Top-level objects” refers to grouping. If you apply the rasterize
filter to a group that contains a rectangle and some text, and then you draw an ellipse within that group, you haven’t added any top-level objects; the ellipse, being contained within a group, isn’t a top-level object.)
I think that “I’m about to Glowforge this; I need to make a PDF and then upload that to GFUI” is easier to remember, and less error-prone, than exporting & re-importing a PNG, or doing any other manual process for copying one layer to a layer of a different format.
Both procedures, namely exporting as a PNG bitmap (then re-importing into Inkscape), and exporting as a PDF (with the rasterize filter), produce another file besides the source SVG, which means, the export steps are a similar number of mouse clicks (re-importing adds more mouse clicks). But the PDF contains both the raster & vector data, and includes the overall size of the design in mm or inches, while the PNG contains only the raster data, and has no scale factor. So I think the PDF is more useful. For instance, you can send or give the PDF electronically to someone to show them what the design looks like, even if they don’t want to use an SVG program such as Inkscape. Or you can print the PDF to an ordinary printer to produce a mockup, including the vector cut/engrave/score lines, without needing to start Inkscape if Inkscape isn’t running at the moment.
Having the file that’s sent to the laser cutter (PDF in my suggested process) be different than your design file (SVG) has the advantage that you can (optionally) leave a “comment” layer visible in the design file, without that layer printing on the laser cutter. We did this, for example, in the business-card design, where we were trying different fonts. Each instance of the business card in the design file has a comment underneath it that says what font(s) were used on that instance. This process can involve:
a. File > Save in the source SVG file;
b. making the “comment” layer invisible;
c. exporting the PDF;
d. Edit > Undo to make the “comment” layer visible and mark the file unmodified so I won’t think I have to save the SVG again.
Item 4.
In Inkscape, I suggest that vector layers (e.g., cut) should be higher in the layer stack than raster layers. I had some vector cuts (the phone number) superimposed on a raster engrave rectangle. If the layer that contains the (raster) rectangle is higher than the (vector) cut layer, then the cuts won’t be visible on your Inkscape screen (unless you happen to make that area of the raster rectangle be transparent).
We also use an invisible layer called “unused”, where we can send unwanted parts of vector clipart instead of deleting them. This way, if we later want a deleted part of the clipart back, we can just pull it back from that layer, instead of having to repeat all steps in standardizing the clipart for our Glowforge design.
Item 5.
I wish someone would try the rasterize-filter method and at least post to this thread that they were able to engrave-and-cut something on their Glowforge with it. Even if that person never uses the technique again.
All you need to do is:
- Put the filter file into your Inkscape filter folder and restart Inkscape.
- Make an Inkscape print-and-cut design.
a. For testing, you don’t have to put the engrave & cut on separate layers if you don’t want to.
b. One of the cases of most interest for this testing is to engrave a complex vector drawing of any kind. As alluded to by mpipes, you should reduce the drawing to monochromatic (I use shades of gray) to keep GFUI from converting it into many engrave steps. I believe you would equally have to edit the drawing to monochrome whether you output in raster or vector form.
c. Another case of interest is to engrave text.
d. But the process is the same whether you do [b] & [c] or not.
- Make sure that any vector item that you want raster-engraved has the
rasterize
filter applied, and that things you want vector-cut/engraved/scored do not have that filter applied. Bitmaps (photos etc.) don’t need the rasterize
filter, since they’re already in raster format.
- File > Save a Copy… as PDF. In the PDF export options dialog, make sure “Rasterize filter effects” is turned on.
- Send the PDF to the Glowforge. As with any Inkscape vector design, you’ll need to specify in GFUI which vector steps are to be cut vs. engraved vs. scored.
When revising the design:
- You never need to do step 1 again on the same computer.
- Step 3 is much simpler if you combine things into groups; then you can just apply the
rasterize
filter to the group. If you do all edits to the group by double-clicking the group as I mentioned in an earlier post, then you don’t have to touch the rasterize
filter again. Only if you add a new group, outside any existing groups (i.e., at the top level of the group hierarchy of your design), would you need to set the new group to be filtered by rasterize
(only once, then the group will retain that filter setting).