# PVRTTriStrip not working even in a simple case.

**URL:** <https://forums.imgtec.com/t/pvrttristrip-not-working-even-in-a-simple-case/1970>\
**Category:** PowerVR Insider\
**Created:** [January 3, 2014, 1:37am UTC](https://forums.imgtec.com/t/pvrttristrip-not-working-even-in-a-simple-case/1970 "2014-01-03T01:37:49Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ahmadhassanch](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@ahmadhassanch](https://forums.imgtec.com/u/ahmadhassanch)\
**Post date:** [January 3, 2014, 1:37am UTC](https://forums.imgtec.com/t/pvrttristrip-not-working-even-in-a-simple-case/1970/1 "2014-01-03T01:37:49Z")

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PVRTTriStrip didn’t seem to work and I generated a very easy problem to see if it finds a solution. I provided it with a 9 triangles which could be easily ordered in ONE triangle strip, but it suggested 9 triangle strips. The input index data is:  
  
  
  
0, 1, 2, 1, 2, 3, 2, 3, 4, 3, 4, 5, 4, 5, 6, 5, 6, 7, 6, 7, 8, 7, 8, 9, 8, 9, 10  
  
  
  
Am I missing something?

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**Author:** ![JoeDavis](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.imgtec.com/joedavis/32/71_2.png) [@JoeDavis](https://forums.imgtec.com/u/JoeDavis)\
**Post date:** [January 27, 2014, 10:33am UTC](https://forums.imgtec.com/t/pvrttristrip-not-working-even-in-a-simple-case/1970/2 "2014-01-27T10:33:04Z")

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Hi Ahmad,  
  
  
  
Apologies for the delayed response. I hadn’t spotted it before as you’d posted in the “FlowCloud Developers” section of the forum. I’ve now moved the discussion to the “PowerVR Insider Graphics” section, as its related to PVRTools.  
  
  
  
I believe the problem is caused by your winding order changing. When the PVRTTriStrip function parses your triangle list, it interprets each triangle with a different winding order as the start of a new triangle list. So, your list should instead be:  
  
  
  
0,1,2,  
  
1,3,2,  
  
2,3,4,  
  
3,5,4,  
  
4,5,6,  
  
5,7,6,  
  
6,7,8,  
  
7,9,8,  
  
8 9,10  
  
  
  
I’ve filed bug report BRN46851 for the function comment to be updated to clarify the required winding order.  
  
  
  
Regards,  
  
Joe

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**Author:** ![ahmadhassanch](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@ahmadhassanch](https://forums.imgtec.com/u/ahmadhassanch)\
**Post date:** [January 27, 2014, 12:05pm UTC](https://forums.imgtec.com/t/pvrttristrip-not-working-even-in-a-simple-case/1970/3 "2014-01-27T12:05:42Z")

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Thanks Joe. Will check it out again.