Is there any way to automatically create diagonals in a polygon?

[Cassio Duarte]

Is there any way to automatically create diagonals in a polygon? I need to make one with 32 sides, with its vertices joined internally creating a mesh. Attached I show what I mean.  Is there this feature in Afinnity Designer?

 

Thanks in advance

[ronnyb]

Nothing automatic that I know of…. But you could step back in your current design to where you only have 1 of the vertices connected to all others, and hit the Return/Enter key, this will bring up a panel for step and repeat type operations. Make sure to check Duplicate, type 31 for the number of steps, and 360/32 degrees for Rotation angle…. 

[NotMyFault]

A polygon and 2 double-stars will do.

your image is distorted a bit, I made a 32 polygon with same x/y size

[Cassio Duarte]

Thanks very much for your help!

[George-Frazee]

edit: Of course as soon as I post I realize how he did it with the stars (got thrown off by the use of the double star). Way easier, but I think the steps below are worth understanding. I'm still thinking their might be a way to adapt this for non regular polygons, if that were ever necessary. Still experimenting.

Like @ronnyb said, you can use the data entry tool to do this. It's not *automatic* per se but using data entry and the node tool you can do this process for any polygon. Two things to keep in mind are that this only works with *regular* polygons, and that sometimes the polygon tool doesn't render the shapes mathematically perfect, so there's some chance a diagonal could be (imperceptibly) not aligned with a vertex of the polygon.

Hopefully the vid is clear (this looks like a lot of steps but it's actually very quick once you get the hang of it)

1. Drop the polygon in the center of the canvas.
2. Use the pen to draw a line from the center to one of the vertices
3. Move the transform origin to the center of the canvas/polygon
4. Hit enter/return for the data entry tool
5. For the "rotation" value, type 360/n where n is the number of sides
6. Check duplicate
7. Set the number of dupes to n - 1.
8. Remove the unneeded lines, in this case the top line and the two adjacent line to the origin of our diagonals
9. Select all the remaining diagonals and select the node tool
10. DRAG to highlight the center nodes (just clicking will only select the top node)
11. Move the node to the vertex of the polygon.
12. From there you can use data entry tool again to make a second set of diagonals.

There's obviously many many ways to approach this but this to me is the least tedious of what I tried. (I also couldn't figure out what @NotMyFault meant by using double stars here and I'd love to see how that works)

 

Edited October 26 by George-Frazee

[NotMyFault]

1 hour ago, George-Frazee said:

got thrown off by the use of the double star). Way easier, but I think the steps below are worth understanding.

I used double stars as the regular star shape on iPad is limited to 48 nodes, too few. 

Your solution is superior when using Desktop. I did not find a way to trigger „move/enter“ tool on iPad (no keyboard attached, no menu entry).

[ronnyb]

9 hours ago, George-Frazee said:

Like @ronnyb said, you can use the data entry tool to do this. It's not *automatic* per se but using data entry and the node tool you can do this process for any polygon. Two things to keep in mind are that this only works with *regular* polygons, and that sometimes the polygon tool doesn't render the shapes mathematically perfect, so there's some chance a diagonal could be (imperceptibly) not aligned with a vertex of the polygon.

Hopefully the vid is clear (this looks like a lot of steps but it's actually very quick once you get the hang of it)

1. Drop the polygon in the center of the canvas.
2. Use the pen to draw a line from the center to one of the vertices
3. Move the transform origin to the center of the canvas/polygon
4. Hit enter/return for the data entry tool
5. For the "rotation" value, type 360/n where n is the number of sides
6. Check duplicate
7. Set the number of dupes to n - 1.
8. Remove the unneeded lines, in this case the top line and the two adjacent line to the origin of our diagonals
9. Select all the remaining diagonals and select the node tool
10. DRAG to highlight the center nodes (just clicking will only select the top node)
11. Move the node to the vertex of the polygon.
12. From there you can use data entry tool again to make a second set of diagonals.

There's obviously many many ways to approach this but this to me is the least tedious of what I tried. (I also couldn't figure out what @NotMyFault meant by using double stars here and I'd love to see how that works)

 

If precision is a concern, make sure to increase decimal place accuracy in the app’s Settings to the highest number of decimal places and Zoom all the way when placing the rotation point/center, as snapping in Affinity is NOT precise unless zoomed in all the way… check and see. Snap at low vs high magnification and then zoom in to see…
 

Also you can use the Join command to connect a central node to each of the outer nodes instead of snapping, but that would be very tedious, useful only if your final use case warrants the efforts…