# contour tree generation

**URL:** https://discourse.paraview.org/t/contour-tree-generation/10269
**Category:** ParaView Support
**Created:** [September 7, 2022, 9:02pm UTC](https://discourse.paraview.org/t/contour-tree-generation/10269 "2022-09-07T21:02:03Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![Pravin\_Poudel](https://discourse.paraview.org/user_avatar/discourse.paraview.org/pravin_poudel/32/9830_2.png) [@Pravin\_Poudel](https://discourse.paraview.org/u/Pravin_Poudel)
#### Post date: [September 7, 2022, 9:02pm UTC](https://discourse.paraview.org/t/contour-tree-generation/10269/1 "2022-09-07T21:02:03Z")

</div>

I have STL file imported in paraview and also have ttl imported and i want to generate contour tree and line in the mesh but FTM filter is disabled when i try to select it.

Can you help me guide what i am supposed to do?

 ![image](https://discourse.paraview.org/uploads/default/original/2X/6/626fa4af9945d0e11957cd6b017c6d1f25d68e0b.png)

I imported the STL file and applied smoothing TTL filter. Now i want to create a contour tree and line.

I am not able to do it.

Can you please help me

---

<div class="post-metadata">

### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [September 8, 2022, 6:28am UTC](https://discourse.paraview.org/t/contour-tree-generation/10269/2 "2022-09-08T06:28:08Z")

</div>

@Charles_Gueunet @julien-tierny

---

<div class="post-metadata">

### Author: ![Charles\_Gueunet](https://discourse.paraview.org/user_avatar/discourse.paraview.org/charles_gueunet/32/40_2.png) [@Charles\_Gueunet](https://discourse.paraview.org/u/Charles_Gueunet)
#### Post date: [September 8, 2022, 7:00am UTC](https://discourse.paraview.org/t/contour-tree-generation/10269/3 "2022-09-08T07:00:41Z")

</div>

Hello @Pravin_Poudel ,

First question, are you sure that your mesh only contains triangle ? If not, you may want to use Tesselate / Tetrahedralize to enforce this.

Then, the contour tree is defined on a mesh with a scalar field. It seems there is none in your current data set. If you want to use the Z-coordinate as a scalar field, you can simply add an elevation filter, setup to use the Z axis. The contour tree should be available then.

Thank you for your interest in TTK !