[SOLVED] [AD] Stroke spills out past bounding box when set to align to center (or outside)

[Anonymous Puddle]

I am trying to get my shape to be a precise size, including its stroke. I cannot simply set the shape to 4 in. tall because the stroke expands that area to more than 4 in. How do I get the bounding box to show me the total area my shape is using, including the stroke? Going to Select > Cycle Selection Box does not do anything here, as I thought it might. Perhaps I'm asking the wrong question to seek the solution but I want the shape AND the stroke to be a total of 4 in., for example.

In the video, the green shape is set to Align to Inside and the red shape is set to Align to center. The red shape's stroke spills over the selection box, or rather the selection box does not update to contain the stroke.

[NotMyFault]

as you already found out, strokes don’t react to snapping or count for bounding box.

but a little math will do the job, using the transform panel.

assuming a centered stroke, use 4in minus 1/2 stroke for width. On Desktop, you can type in simple math formulas directly.

On iPad, use a calculator, spreadsheet, etc.

[Anonymous Puddle]

@NotMyFault Disappointing that that's the only way... It's quite convoluted.

[Anonymous Puddle]

EUREKA! The solution is to use Expand Stroke. From the menu bar, go to Layer > Expand Stroke. This will convert your stroke to a closed shape, and the bounding box will adjust to accommodate the size of the stroke. Now, I can achieve the exact size shape I want, including the size of the stroke!

Here is the help article on it, for anyone interested: https://affinity.help/designer2/en-US.lproj/index.html?page=pages/CurvesShapes/expandStroke.html&title=Expand stroke

[GarryP]

On 12/30/2024 at 7:12 PM, Anonymous Puddle said:

I want the shape AND the stroke to be a total of 4 in., for example.

I don’t understand why you cannot use “Align to Inside” as you have done with the green rectangle in your video.

If the stroke is aligned to the inside then the external dimensions of the shape (including the stroke) will be those which you set in the Transform Panel.

See attached image.

Is there some important information that I’m missing or not understanding?

[Anonymous Puddle]

1 minute ago, GarryP said:

I don’t understand why you cannot use “Align to Inside” as you have done with the green rectangle in your video.

I did not mention it but it is because I had been wanting rounded corners with the stroke. When I select "Align to Inside", the corners are squared off.

[GarryP]

Ah, I see.

Have you tried setting the Corner for the Rectangle to Rounded via the Context Toolbar?

[Anonymous Puddle]

@GarryP Ah, nice tip! That could be helpful. That option does not show up for more complex curves though- in which case I imagine one would need to utilize Expand Stroke.

[carl123]

14 minutes ago, Anonymous Puddle said:

@GarryP Ah, nice tip! That could be helpful. That option does not show up for more complex curves though- in which case I imagine one would need to utilize Expand Stroke.

There's a Corner Tool in Designer that may be useful to you

[GarryP]

As carl123 has just mentioned, you can use the Corner Tool for some shapes but the result would, of course, depend on the geometry of the original shape.

It’s worth noting that, under certain conditions, “Align to Inside” and “Align to Outside” might not produce a result which is ‘perfect’ because of various technical reasons.

Sometimes there is a very thin curve of either the shape’s fill colour (when using “Align to Inside”) or a very thin curve which lets the background ‘shine through’ (when using “Align to Outside”). Basically the geometries of the fill and the geometries of the stroke are calculated separately and the results of those calculations don’t always ‘match’ exactly.

See my attached image where you can see that using “Align to Inside” has caused the outside edge of the red fill to be visible outside of the yellow stroke by a tiny amount. (You might need to zoom in to the image to see it clearly.)

There are some ‘workarounds’ for those occasions but the effectiveness of these can vary.

[Anonymous Puddle]

@GarryP How fascinating! 

9 minutes ago, carl123 said:

There's a Corner Tool in Designer that may be useful to you

Unless I'm missing something, there is no way to use the corner tool to expand the corners outward. I'm assuming you are suggesting to set the stroke to "Align to Inside", then use the corner tool to round the corners. The Corner tool can only round corners inward, not outward. Even testing the Contour tool, which I can use to round the corners outward, gives me undesirable results with imprecise and even jagged corners compared to the same shape with the stroke set to "Align to Center".

These are great tips, and thank you both or pointing them out! However, (correct me if I'm wrong) it seems that Expand Stroke is still the best option for precise results.

[GarryP]

Yes, the Corner Tool will only add corners inside the original shape, a bit like using a plane or other tool to put a corner on a piece of wood.

You can use the Contour Tool to expand the shape outside of its original geometry (use it on a duplicate so you don’t lose the original) but the effectiveness of the results, as usual, depend on the original shape and what you are trying to do.

However, using the Contour Tool would mean that the dimensions of the shape would grow so I don’t know how adding a corner to the outside of your shape using that would match up with your original issue.