Zoom and the models seem distorted

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Debbie
Posts: 6
Joined: Wed Aug 14, 2019 7:18 am

Zoom and the models seem distorted

Post by Debbie »

Make two cubes close to each other and no gaps between them. Zoom the camera continuously and they become distorted at the adjoning part.
It seems something is wrong with the projection. Has anybody seen this before?

OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.16131 (Git)
Build type: Release
Branch: releases/FreeCAD-0-18
Hash: 3129ae4296e40ed20e7b3d460b86e6969acbe1c3
Python version: 3.6.6
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
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chrisb
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Posts: 54302
Joined: Tue Mar 17, 2015 9:14 am

Re: Zoom and the models seem distorted

Post by chrisb »

I guess it's just the display. You can try to reduce the values of the view properties "Deviation" and "Angular deflection". Be prepared for recalculation time to increase.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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Debbie
Posts: 6
Joined: Wed Aug 14, 2019 7:18 am

Re: Zoom and the models seem distorted

Post by Debbie »

chrisb wrote: ↑Fri Sep 18, 2020 6:22 am I guess it's just the display. You can try to reduce the values of the view properties "Deviation" and "Angular deflection". Be prepared for recalculation time to increase.
The problem still exists when changing deviation to 0.01 and angular deflection to 1 for both models.
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chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Zoom and the models seem distorted

Post by chrisb »

The effect vanishes here as soon as the adjacent face is preselected, i.e. if the mouse is over it.
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chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Zoom and the models seem distorted

Post by chrisb »

The effect seems to vanish if you switch preselection off, but it returns if I try to turn the model in 3D view at this extreme zoom level. Perhaps we are getting near the rounding/precision of the internal representation of lines and faces.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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Debbie
Posts: 6
Joined: Wed Aug 14, 2019 7:18 am

Re: Zoom and the models seem distorted

Post by Debbie »

chrisb wrote: ↑Fri Sep 18, 2020 7:23 am The effect seems to vanish if you switch preselection off, but it returns if I try to turn the model in 3D view at this extreme zoom level. Perhaps we are getting near the rounding/precision of the internal representation of lines and faces.
If it's the precision, how to find the critical value to avoid the weird display ? Maybe we can prevent zoom endlessly.

Besides when this issue happens, the camera:

'#Inventor V2.1 ascii\n\n\nOrthographicCamera {\n viewportMapping ADJUST_CAMERA\n position 11.474792 -6.630055 15.372829\n orientation 0.9595412 0.079511285 0.27010769 0.93908507\n nearDistance 6.9503541\n farDistance 24.24716\n aspectRatio 1\n focalDistance 8.6602545\n height 4.3380373e-006\n\n}\n'

The height value seems a little abnormal ?
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