# Rendering Issues in iOS

**URL:** <https://discourse.threejs.org/t/rendering-issues-in-ios/38753>\
**Category:** Questions\
**Tags:** mobile\
**Created:** [June 1, 2022, 8:07pm UTC](https://discourse.threejs.org/t/rendering-issues-in-ios/38753 "2022-06-01T20:07:57Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Tilman](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/tilman/32/26713_2.png) [@Tilman](https://discourse.threejs.org/u/Tilman)\
**Post date:** [June 1, 2022, 8:07pm UTC](https://discourse.threejs.org/t/rendering-issues-in-ios/38753/1 "2022-06-01T20:07:57Z")

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i have a 3d-multiuser space with headless physics running for a client and for some reason along the development a strange rendering issue showed up that i can’t find the root of. it looks like the screen is not being cleared during redraw/rendering causing objects to smear/duplicate etc. on a random basis. pls see attached screens or try yourself at [https://collaboratory-lenbachhaus.de](https://collaboratory-lenbachhaus.de)

 ![image](https://canada1.discourse-cdn.com/flex035/uploads/threejs/original/3X/1/a/1a7e4873796638c44584b4fb5a0f9c2834873515.jpeg)  
 ![image](https://canada1.discourse-cdn.com/flex035/uploads/threejs/original/3X/6/8/68cc23c71462ea9fbb94f1e204c93702c2652978.jpeg)

Do you have any idea what might cause this issue?

thanks a lot!

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<div class="post-metadata">

**Author:** ![Tilman](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/tilman/32/26713_2.png) [@Tilman](https://discourse.threejs.org/u/Tilman)\
**Post date:** [June 1, 2022, 9:00pm UTC](https://discourse.threejs.org/t/rendering-issues-in-ios/38753/2 "2022-06-01T21:00:56Z")

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update: the issues seems to go away temporarily when rotating the device…

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<div class="post-metadata">

**Author:** ![vielzutun.ch](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/vielzutun.ch/32/21366_2.png) [@vielzutun.ch](https://discourse.threejs.org/u/vielzutun.ch)\
**Post date:** [June 2, 2022, 3:41am UTC](https://discourse.threejs.org/t/rendering-issues-in-ios/38753/3 "2022-06-02T03:41:50Z")

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This issue (and fix) has been [reported before](https://discourse.threejs.org/t/objects-render-multiple-times/38319) and seems to be a WebKit bug.