# Cannon read property "read" of undefined in Polygonception

**URL:** <https://discourse.codecombat.com/t/cannon-read-property-read-of-undefined-in-polygonception/5451>\
**Category:** Ambassador\
**Created:** [October 28, 2015, 4:34pm UTC](https://discourse.codecombat.com/t/cannon-read-property-read-of-undefined-in-polygonception/5451 "2015-10-28T16:34:26Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![jbum](https://sea2.discourse-cdn.com/flex016/user_avatar/discourse.codecombat.com/jbum/32/3163_2.png) [@jbum](https://discourse.codecombat.com/u/jbum)\
**Post date:** [November 16, 2015, 9:17pm UTC](https://discourse.codecombat.com/t/cannon-read-property-read-of-undefined-in-polygonception/5451/2 "2015-11-16T21:17:49Z")

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I’m curious if you got past this because I am having the same problem. I believe I am passing valid vectors to the drawPolygon function, but inside the function it is treating them as undefined. My code looks very similar to yours.

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