# Draw cartographic polygon in runtime

**URL:** <https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738>\
**Category:** Cesium for Unreal\
**Created:** [May 2, 2023, 9:27am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738 "2023-05-02T09:27:40Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Leedia](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/leedia/32/12621_2.png) [@Leedia](https://community.cesium.com/u/Leedia)\
**Post date:** [May 2, 2023, 9:27am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738/1 "2023-05-02T09:27:40Z")

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Hello,  
I have a list of cartographic positions (long/lat/alt) and I want to draw a cartographic polygon in runtime, is there a way to do it in blueprint or should i do it in c++ ?

Thanks !

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**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\
**Post date:** [May 4, 2023, 12:42am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738/2 "2023-05-04T00:42:47Z")

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I think you should be able to get the `Polygon` (which is a USplineComponent`) from Blueprints and modify it. Try it and let us know how it goes!

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**Author:** ![Leedia](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/leedia/32/12621_2.png) [@Leedia](https://community.cesium.com/u/Leedia)\
**Post date:** [May 4, 2023, 7:17am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738/3 "2023-05-04T07:17:59Z")

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that’s what i did and i got a crash saying access violation. Before digging any deeper into that, is it possible to define an extruded height within the polygon ?

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<div class="post-metadata">

**Author:** ![Leedia](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/leedia/32/12621_2.png) [@Leedia](https://community.cesium.com/u/Leedia)\
**Post date:** [May 4, 2023, 7:24am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738/4 "2023-05-04T07:24:22Z")

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also, is it any different if I used just a spline instead of the spline of cartographic polygon ?

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<div class="post-metadata">

**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\
**Post date:** [May 4, 2023, 11:25am UTC](https://community.cesium.com/t/draw-cartographic-polygon-in-runtime/23738/5 "2023-05-04T11:25:36Z")

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> that’s what i did and i got a crash saying access violation.

That’s strange. If you believe the access violation is a result of something Cesium for Unreal is doing wrong, please share the call stack and instructions for reproducing the crash.

> Before digging any deeper into that, is it possible to define an extruded height within the polygon ?

No, it’s not currently possible to specify heights for the polygon.

> also, is it any different if I used just a spline instead of the spline of cartographic polygon ?

I’m not quite sure what you’re asking here.