How do I make a dashed line SOP?

[matijaerceg]

I’d like to make a simple point A to point B straight line SOP, but I’d like it to render like a dashed line with configurable thickness (a la Wireframe MAT Line Width parameter).

I’m thinking, if the Line SOP has 20 segments, and every second segment is deleted, it would give a dashed line. Or something like that… Is there a way to do this easily?

My priority is the appearance of a dashed line, not the geometry, so if it’s easy to do with a MAT, that would work for me also.

[nettoyeur]

there are some different solutions to be found if you search the forum for “dashed”, here’s one:

Strokes and dashed strokes over shapes

Hello, I am trying to apply regular strokes or dashed strokes (probably will be switchable later) over the triangle. I am starting from drawing the triangle with the circle TOP and the circle SOP; haven’t figured out which one works better for my purpose. My questions are: With the circle SOP (in the file), is it possible to draw regular and dashed strokes over the triangle? [Screen Shot 2021-07-14 at 5.52.41 PM] With the circle TOP (in the file), I was able to draw the stroke in the pa…

[matijaerceg]

Thx for the pointer!

I ended up using a modified solution from that thread, where you first split up the line into many segments, group half of them in sets, set the group’s alpha to 0, and use a wireframe material to set thickness. I don’t think wireframe would work as a MAT on SOPs that aren’t a straight line though, which is why the other thread probably used the Constant or Line MATs.

For anyone in the future who might care to see, here’s my tox:

dashed-line-basic.tox (7.8 KB)

For what it’s worth, I’d still be interested to see if anyone knows of a way to ‘dash’ at the SOP level, rather than the material level, as I noticed that the dashes are filtered/soft, and if it was the actual geometry that was dashed, the dashes would have perfect hard ends. Notice the fade/black on each dash here:

[ab_out]

Made something quick that seems to be doing what you’re looking for with some extra control:

Here’s the network:

• SOP using just 2 points A to B
• render it out (lately i’m always using the “cameraViewport” (see the pallete) camera as it allows you to easily and interactively set the camera…)
• Use const MAT that allows you to set a color map => just start from a patternCHOP and convert to the TOP domain + in the MAT’s common page set Wire frame and start playing with the line width

While wrinting this answer i notice a similar softening when zooming in on the dashed line. However, by increasing the pattern Length parameter this effect is reduced significantly.
=> added a second solution in the .toe that eliminates the softening by doing everything in the SOP domain using some convertSOPs and a joinSOP that joins by groups of N premitives… This allows you to use the line MAT and set the line width from there

dashedLineSOP.7.toe (25.1 KB)

Hope this helps

[matijaerceg]

Thanks for taking a stab @ab_out

@ab_out

i notice a similar softening

Since you’re using a color map in the first solution, you can actually just change it to use Nearest Neighbor filtering, which takes care of the softness:

Your second solution, however, is exactly what I was hoping for! Thanks