# Sprite Overlap Not Working

**URL:** <https://forum.makecode.com/t/sprite-overlap-not-working/29162>\
**Category:** Arcade\
**Created:** [June 7, 2024, 9:38pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162 "2024-06-07T21:38:36Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![MrHM](https://avatars.discourse-cdn.com/v4/letter/m/7993a0/32.png) [@MrHM](https://forum.makecode.com/u/MrHM)\
**Post date:** [June 7, 2024, 9:38pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162/1 "2024-06-07T21:38:36Z")

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Hello, pulled up a version of Flappy Bird I developed back in 2020ish. My overlap between PLAYER and ENEMY works just fine. But now the overlap between PLAYER and SCORING LINE never seems to fire. Has something changed since then?

> **[FlappyBirdKHakesMiller](https://arcade.makecode.com/S48750-29647-97258-29071)**
>
> Made with ❤️ in Microsoft MakeCode Arcade.

Thanks!

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**Author:** ![richard](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.makecode.com/richard/32/5417_2.png) [@richard](https://forum.makecode.com/u/richard)\
**Post date:** [June 7, 2024, 9:42pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162/2 "2024-06-07T21:42:11Z")

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hmm, i think this might be caused by floating point errors when the width of a sprite is 1 pixel. if you change the scoring line to be 2 pixels wide, it should fix the issue

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**Author:** ![MrHM](https://avatars.discourse-cdn.com/v4/letter/m/7993a0/32.png) [@MrHM](https://forum.makecode.com/u/MrHM)\
**Post date:** [June 9, 2024, 5:08pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162/3 "2024-06-09T17:08:55Z")

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That did the trick. Appreciate the pointer. Wonder what changed in the last 4ish years to introduce the silent failure.

All the best

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**Author:** ![richard](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.makecode.com/richard/32/5417_2.png) [@richard](https://forum.makecode.com/u/richard)\
**Post date:** [June 10, 2024, 4:50pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162/4 "2024-06-10T16:50:24Z")

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@MrHM we’ve rewritten the physics engine a couple times in order to improve performance on hardware… our physics engine now uses fixed point arithmetic for all the math which improves perf a lot but might have broken this scenario

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**Author:** ![MrHM](https://avatars.discourse-cdn.com/v4/letter/m/7993a0/32.png) [@MrHM](https://forum.makecode.com/u/MrHM)\
**Post date:** [June 10, 2024, 8:27pm UTC](https://forum.makecode.com/t/sprite-overlap-not-working/29162/5 "2024-06-10T20:27:06Z")

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Yes, seems broken for such a fundamental building block of games. Had to widen the sprite to 4 pixels to get reliable triggering of the overlap. 2 pixels wide resulting in triggering about 80% of the time. Hopefully fixable. Thanks again for the help.