# Weird shadow lines drawn on my lightmap ?

**URL:** <https://forums.unrealengine.com/t/weird-shadow-lines-drawn-on-my-lightmap/327761>\
**Category:** Rendering\
**Tags:** shading, unreal-engine, Lightmap, question\
**Created:** [August 5, 2015, 4:46pm UTC](https://forums.unrealengine.com/t/weird-shadow-lines-drawn-on-my-lightmap/327761 "2015-08-05T16:46:21Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![anonymous\_user\_cc69b907](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_cc69b907](https://forums.unrealengine.com/u/anonymous_user_cc69b907)\
**Post date:** [August 5, 2015, 6:01pm UTC](https://forums.unrealengine.com/t/weird-shadow-lines-drawn-on-my-lightmap/327761/2 "2015-08-05T18:01:12Z")

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Hello .colas -

So there seems to be a few things that are happening with your model.

In the first image, inside of Maya, it appears as if you have seams everywhere. The thick green lines are indicative of where your geometry does not meet.

That’s the pre UE4 issue that I see.

Inside of UE4 make sure you have assigned the light map channel to your mesh inside of the meshes detail panel.

I am going to link you our lighting troubleshooting guide on our wiki.

> **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)**
>
> After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — https://unrealcommunity.wiki/! You will be able to find content from...

This should help clarify/guide you with any lighting issues that could be occurring in your scene.

Thanks,

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