# Arcade collision issue (tween)

**URL:** <https://phaser.discourse.group/t/arcade-collision-issue-tween/7199>\
**Category:** Phaser 3\
**Created:** [August 16, 2020, 9:34am UTC](https://phaser.discourse.group/t/arcade-collision-issue-tween/7199 "2020-08-16T09:34:12Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![schlemmi](https://yyz2.discourse-cdn.com/free1/user_avatar/phaser.discourse.group/schlemmi/32/3278_2.png) [@schlemmi](https://phaser.discourse.group/u/schlemmi)\
**Post date:** [August 16, 2020, 9:34am UTC](https://phaser.discourse.group/t/arcade-collision-issue-tween/7199/1 "2020-08-16T09:34:12Z")

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I have an odd issue in a scene with a tweened body & a sprite, where the sprite will sometimes ‘fall through’ the body - i.e. the collision doesn’t happen. sometimes the collision works ok.

the code for the tweened body is copied from:  
[https://www.phaser.io/examples/v3/view/physics/arcade/tween-body](https://www.phaser.io/examples/v3/view/physics/arcade/tween-body)  
except that the sprite has a circular collision shape.  
the sprite is moved by setting acceleration and by regular y gravity

Looks like a bug to me…

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**Author:** ![BlunT76](https://yyz2.discourse-cdn.com/free1/user_avatar/phaser.discourse.group/blunt76/32/1454_2.png) [@BlunT76](https://phaser.discourse.group/u/BlunT76)\
**Post date:** [August 16, 2020, 9:56pm UTC](https://phaser.discourse.group/t/arcade-collision-issue-tween/7199/2 "2020-08-16T21:56:32Z")

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Hi

Post your code, or codepen/fiddle to test it please

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<div class="post-metadata">

**Author:** ![schlemmi](https://yyz2.discourse-cdn.com/free1/user_avatar/phaser.discourse.group/schlemmi/32/3278_2.png) [@schlemmi](https://phaser.discourse.group/u/schlemmi)\
**Post date:** [August 22, 2020, 2:23am UTC](https://phaser.discourse.group/t/arcade-collision-issue-tween/7199/3 "2020-08-22T02:23:33Z")

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It appears to be related to the  
block.body.moves = false  
if I remove that, make it a normal body & move it (setVelocity()) then it works ok.  
(it’s not related to the circular collision shape. regular (square) collision shape has the same issue)  
the manual says that ‘moves=false’ should be used with a tween or drag.  
my guess is that the tween move step is sometimes more than the collision can handle.  
I’ll try put some code somewhere. it might take some time.

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<div class="post-metadata">

**Author:** ![samme](https://yyz2.discourse-cdn.com/free1/user_avatar/phaser.discourse.group/samme/32/5275_2.png) [@samme](https://phaser.discourse.group/u/samme)\
**Post date:** [August 24, 2020, 8:29pm UTC](https://phaser.discourse.group/t/arcade-collision-issue-tween/7199/4 "2020-08-24T20:29:55Z")

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The same thing will happen in that example if the velocity is increased or the overlap bias is decreased. Moving physics sprites directly (e.g. tweens, input) tends to cause separation failures.