AD 2.2.0 Stroke precision and zoom issue

[ErikA310]

Good morning,

I have some issue with stroke precision and and stroke display when zooming in. I have a (rounded) rectangle positioned on y=5mm and specified  6mm inner aligned stroke (calculated by app to 17.01pt). Calculating back from pt to mm this computes to 6,00075mm. So the stroke should end at 11.00075mm. Looking at attached image Zoom1  you will find that the end is rather displayed at 11.05mm instead. I assume there is some rounding issue.

When you further zoom in either the calculation is showing a different issue or a redraw problem, please see Zoom2.png. Shape ends now above the 11mm guide

Can you please have a look?

Thanks and best regards,
Erik

[MacBook Pro M1 Max 16", Metal enabled, Sonoma 14.0]

[Hangman]

Hi @ErikA310,

2 hours ago, ErikA310 said:

I have some issue with stroke precision and and stroke display when zooming in. I have a (rounded) rectangle positioned on y=5mm and specified  6mm inner aligned stroke (calculated by app to 17.01pt). Calculating back from pt to mm this computes to 6,00075mm. So the stroke should end at 11.00075mm. Looking at attached image Zoom1  you will find that the end is rather displayed at 11.05mm instead. I assume there is some rounding issue.

1 mm = 2.8346438836889 pts
6 mm = 17.007863302133 pts

Therefore

1 pt = 0.352777999999999 mm
17.007863302133 pts = 5.999999999999859 mm
17.01 pts = 6.000753779999983 mm

or Rounded to six decimal places (the accuracy of Affinity apps)

1 pt = 0.352778 mm
17.007863302133 pts = 6.000000 mm
17.01 pts = 6.000754 mm

In your first screengrab, it's showing y = 5.05 mm so the expectation is that the inner edge of the stroke will appear at 11.05 mm which it does.

There have always been redraw issues when zooming in very close, I don't know if this is something that will ever be fixed but it's been there from day 1.

[walt.farrell]

I wonder if it would help @ErikA310 to adjust the application Settings to show lines in the document units rather than in points? That removes the need for the user to do the conversions between mm and pt.

That should be in the User Interface section of the Designer Settings.

[ErikA310]

Thanx @Hangman@walt.farrell,

for pointing out my mistakes with respect to unit conversion and positioning/alignment. After correction this looks much better (see Zoom3.png).
Nevertheless the zoom issue still persists, or is this also my mistake/misunderstanding of the app's behaviour?

At some level of zooming in the stroke is not painted as expected. Please refer to attachment Zoom4. The glitch is also showing some variance. Zooming in. via cmd+ and zooming out via cmd- does not necessarily mean. Glitch visible, glitch invisible. Sometimes I have to zoom out two times to get the 'correct' visual representation back. Any idea about this?

Thank you and best regards,
Erik

[Hangman]

Hi @ErikA310,

That's no problem at all, I'm glad you have the unit conversion and positioning/alignment issues resolved.

For the screen re-draw issue, one thing you can try is to disable Hardware Acceleration under the Performance Settings to see if either makes any difference when zooming.