# Invisible volumes when using "Warp by vector" filter
**URL:** https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539
**Category:** ParaView Support
**Created:** [June 8, 2020, 4:32pm UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539 "2020-06-08T16:32:35Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Golho](https://discourse.paraview.org/u/Golho)
#### Post date: [June 8, 2020, 4:32pm UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539/1 "2020-06-08T16:32:36Z")
Hi!
**I’m using**
- Paraview 5.8.0
- Windows 10, 64-bits, x64 system
**What I want to do:**
I want to display a scalar field over the cells of a structured grid, by using the volume representation (so I may use the _Multi Components Mapping_) and at the same time show the displacements of the nodes (by using the _Warp by vector_ filter).
**What happens:**
I use the following VTK-file as data input:
```
# vtk DataFile Version 3.0
vtk output
ASCII
DATASET STRUCTURED_POINTS
DIMENSIONS 3 3 1
SPACING 1 1 1
ORIGIN 0 0 0
CELL_DATA 4
SCALARS scalars float 2
LOOKUP_TABLE default
0 0
0.4 0
0.4 1
0 1
POINT_DATA 9
VECTORS vect3 float
-1 -1 0
-1 -1 0
-1 -1 0
-1 0 0
-1 0 0
-1 0 0
-1 1 0
-1 1 0
-1 1 0
```
then, when importing to Paraview, I use the _Warp by vector_ filter on **vect3** and then display **scalars** with a volume representation.
The problem is that the volume is now invisible, and it doesn’t matter if I check the _Multi components mapping_ checkbox or not.
Am I doing something wrong maybe? I have tried to simplify the example as much as possible, and hope it should be obvious what I want to achieve.
EDIT: Here’s a picture of how it looks like when the volumes are invisible
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [June 9, 2020, 1:32am UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539/2 "2020-06-09T01:32:03Z")
You data is 2D. VolumeRendering of 2D data is not supported.
What kind of visualization are you expecting when volume rendering 2D data ?
---
### Author:  [@Golho](https://discourse.paraview.org/u/Golho)
#### Post date: [June 12, 2020, 10:02am UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539/3 "2020-06-12T10:02:55Z")
Woops, I didn’t even reflect over that fact, thank you for pointing that out!
The reason I want to use volume rendering is as I mentioned before: I want to use Multi Component Mapping on my two component scalar field. And this would include visualising 2D geometries this way.
If I extend the data to 3D, 1 element thick in the z-dimension, it works fine 🙂
However, I encounter another small issue this time. Using this file:
```
# vtk DataFile Version 3.0
vtk output
ASCII
DATASET STRUCTURED_POINTS
DIMENSIONS 3 3 2
SPACING 1 1 1
ORIGIN 0 0 0
CELL_DATA 4
SCALARS scalars float 2
LOOKUP_TABLE default
0.4 0
0 0
0.4 1
0 1
POINT_DATA 18
VECTORS vect3 float
-1 -1 0
-1 -1 0
-1 -1 0
-1 0 0
-1 0 0
-1 0 0
-1 1 0
-1 1 0
-1 1 0
-1 -1 0
-1 -1 0
-1 -1 0
-1 0 0
-1 0 0
-1 0 0
-1 1 0
-1 1 0
-1 1 0
```
I get this error message when using Multi Component Mapping on the scalar field.
In this video you see the steps I take (the error message box is however not captured in the video):
I guess there is some formatting error in the VTK file that is not breaking, but still not 100% correct. I have however a hard time finding a good VTK reference to guide me. Do you know what could be the problem here?
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [June 15, 2020, 4:39am UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539/4 "2020-06-15T04:39:12Z")
Small bug in ParaView forcing the coloring by point data, you seems to have figured it out that you need to reselect the cell data array to fix it.
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [June 15, 2020, 4:44am UTC](https://discourse.paraview.org/t/invisible-volumes-when-using-warp-by-vector-filter/4539/5 "2020-06-15T04:44:18Z")
[https://gitlab.kitware.com/paraview/paraview/-/issues/19991](https://gitlab.kitware.com/paraview/paraview/-/issues/19991)