# Status of Quads on the Interface

**URL:** https://precice.discourse.group/t/status-of-quads-on-the-interface/254
**Category:** Is preCICE for me?
**Tags:** data-mapping
**Created:** [June 16, 2020, 4:31pm UTC](https://precice.discourse.group/t/status-of-quads-on-the-interface/254 "2020-06-16T16:31:57Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![bodony](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bodony](https://precice.discourse.group/u/bodony)
#### Post date: [June 16, 2020, 4:31pm UTC](https://precice.discourse.group/t/status-of-quads-on-the-interface/254/1 "2020-06-16T16:31:57Z")

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Hello,

According to the v2.1.0 milestones, there is an effort to enable quads be present on a coupling interface. What is (a) the likelihood that quad functionality will be ready by the stated July, 2020, target date and (b) what quad functionality is expected?

Thank you.  
Dan

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### Author: ![KyleDavisSA](https://yyz2.discourse-cdn.com/free1/user_avatar/precice.discourse.group/kyledavissa/32/108_2.png) [@KyleDavisSA](https://precice.discourse.group/u/KyleDavisSA)
#### Post date: [June 19, 2020, 11:38am UTC](https://precice.discourse.group/t/status-of-quads-on-the-interface/254/2 "2020-06-19T11:38:23Z")

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Hi,

special treatment for quad elements is only necessary for the nearest-projection mapping method. In this case in preCICE, this will involve receiving the four vertices, or four edges, of a quad and splitting it into two seperate triangles, where normal NP mapping functionality already available in preCICE is used. There is a PR currently for this. Is there any specific functionality that you require from quad elements? They can already be used with nearest-neighbor and RBF methods.

Regards  
Kyle

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### Author: ![bodony](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bodony](https://precice.discourse.group/u/bodony)
#### Post date: [June 19, 2020, 1:23pm UTC](https://precice.discourse.group/t/status-of-quads-on-the-interface/254/3 "2020-06-19T13:23:37Z")

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Thank you. I’m preparing to evaluate preCICE and one solver uses structured meshes, leading to the question. We’ll try preCICE and test both the NN and the RBF methods.

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### Author: ![KyleDavisSA](https://yyz2.discourse-cdn.com/free1/user_avatar/precice.discourse.group/kyledavissa/32/108_2.png) [@KyleDavisSA](https://precice.discourse.group/u/KyleDavisSA)
#### Post date: [June 22, 2020, 6:12am UTC](https://precice.discourse.group/t/status-of-quads-on-the-interface/254/4 "2020-06-22T06:12:16Z")

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If you need to evaluate quad meshes, and potentially non-linear quad meshes where there may be an extra node on the edges, it is possible to split the quad face into triangles in your adapter and then use the normal NP mapping of triangles. This is extra work and solver dependent, but may give you more freedom in using NP mapping.

Regards  
Kyle
