# Error while rendering volumetric webgl2 example with different dataset

**URL:** <https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462>\
**Category:** Questions\
**Tags:** nrrd-loader\
**Created:** [September 1, 2021, 7:12am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462 "2021-09-01T07:12:01Z")\
**Posts on this page:** 12\
**Page:** 1

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**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 1, 2021, 7:12am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/1 "2021-09-01T07:12:01Z")

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Hi Guys,  
I am new to threeJS so this may be an obvious problem:  
When I render the example:  
[https://threejs.org/examples/?q=webgl2#webgl2\_materials\_texture3d](https://threejs.org/examples/?q=webgl2#webgl2_materials_texture3d)  
it works fine (off examples page or using LiveServer).

But when I use a different nrrd file, I get the following error:  
INVALID\_OPERATION: texImage3D: type FLOAT but ArrayBufferView not Float32Array.  
The stack looks like:  
texImage3D @ three.module.js:20208  
uploadTexture @ three.module.js:20971  
setTexture3D @ three.module.js:20683  
setValueT3D1 @ three.module.js:16187  
WebGLUniforms.upload @ three.module.js:16660  
setProgram @ three.module.js:24864  
WebGLRenderer.renderBufferDirect @ three.module.js:23933  
renderObject @ three.module.js:24486  
renderObjects @ three.module.js:24458  
WebGLRenderer.render @ three.module.js:24258

The nrrd files look fine in Slicer. The only difference is that the example nrrd file is 861kb compared to the 7.5mb file I am trying. IMO, from a c++ world it looks like a type mismatch somewhere, but any suggestion would be greatly appreciated!

Thanks  
-AM

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<div class="post-metadata">

**Author:** ![Mugen87](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/mugen87/32/5645_2.png) [@Mugen87](https://discourse.threejs.org/u/Mugen87)\
**Post date:** [September 1, 2021, 8:50am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/2 "2021-09-01T08:50:33Z")

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Can you share the NRRD file in this thread?

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 1, 2021, 12:16pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/3 "2021-09-01T12:16:41Z")

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[KneeError.nrrd](https://discourse.threejs.org/uploads/short-url/fA3Sx4KNn0wiTSg26jcFEl7ZBRW.nrrd) (2.0 MB)

Hi @Mugen87 ,  
Thanks for looking into it! I have uploaded the nrrd file that is causing the error. I had to cut it out a bit to satisfy the upload limit.  
Thanks  
-AM

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<div class="post-metadata">

**Author:** ![Mugen87](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/mugen87/32/5645_2.png) [@Mugen87](https://discourse.threejs.org/u/Mugen87)\
**Post date:** [September 1, 2021, 2:11pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/4 "2021-09-01T14:11:47Z")

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Um, I get a totally different error when loading the asset with `NRRDLoader`.

> [@stresstensor](#):
>
> I had to cut it out a bit to satisfy the upload limit.

What do you mean with “cut”^^? It’s probably better to share the entire asset via Google Drive or a similar service.

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 1, 2021, 3:02pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/5 "2021-09-01T15:02:26Z")

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I took out some of the last few layers to reduce the file size. I still get the same error with the file I posted. I have tried a few other nrrd files and get the same error.

Here is the original knee that I got the error:

> **[Knee.nrrd](https://www.dropbox.com/s/qr6x9e5jx2bv684/Knee.nrrd?dl=0)**
>
> Shared with Dropbox

@Mugen87 , just curious, what was your error?

Thanks again!  
-AM

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 2, 2021, 2:46am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/6 "2021-09-02T02:46:10Z")

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Another interesting observation is if I run the example with the Knee.nrrd file on Firefox (via LiveServer), the message is different:  
WebGL warning: tex(Sub)Image[23]D: ArrayBufferView type Int16 not compatible with `type` FLOAT.

Thanks  
-AM

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<div class="post-metadata">

**Author:** ![Mugen87](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/mugen87/32/5645_2.png) [@Mugen87](https://discourse.threejs.org/u/Mugen87)\
**Post date:** [September 2, 2021, 8:47am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/7 "2021-09-02T08:47:18Z")

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> [@stresstensor](#):
>
> @Mugen87 , just curious, what was your error?

When loading the asset into `webgl_loader_nrrd` example I get this message three times (for each slice mesh).

> three.module.js:9862 THREE.BufferGeometry.computeBoundingSphere(): Computed radius is NaN. The “position” attribute is likely to have NaN values.

The `position` attribute of the plane does indeed have `NaN` values.

After some debugging it seems this happens because of the following code section:

> <https://github.com/mrdoob/three.js/blob/ee9e1e76b2d150123dbc98cf5e9a7b16a9b11f70/examples/jsm/loaders/NRRDLoader.js#L368-L380>

With your asset, the resulting axis order is just `['z']` because `xIndex`, `yIndex` and `zIndex` are all zero. That happens because the code assume an axis definition looks like so:

```javascript
[0.9375000000000002, 0, 0]

```

However, in your asset it looks like so:

```javascript
[0.3319472434711307, 0.00012250095587679915, 0.00591713997077279]

```

Since there are no `0` values, the code can’t detect the axis order.

I don’t know NRRD but it would be important to know whether the standard allows such definitions. If so, the loader requires a change.

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 2, 2021, 7:51pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/8 "2021-09-02T19:51:19Z")

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I am no expert in nrrd either. The nrrd files are from:  
[https://public.cancerimagingarchive.net/nbia-search/](https://public.cancerimagingarchive.net/nbia-search/)

What still puzzles me is how your error is different. I however still get the texImage3D: type FLOAT but ArrayBufferView not Float32Array error. I also tried with cdn.skypack.dev version of three JS, just in case my local version is older.

Thanks  
-AM

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<div class="post-metadata">

**Author:** ![Mugen87](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/mugen87/32/5645_2.png) [@Mugen87](https://discourse.threejs.org/u/Mugen87)\
**Post date:** [September 2, 2021, 9:15pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/9 "2021-09-02T21:15:15Z")

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> [@stresstensor](#):
>
> I however still get the texImage3D: type FLOAT but ArrayBufferView not Float32Array error.

I did not try to use a 3D texture. I just want to test if the loader is able to load the file so it can be rendered as planes like in `webgl_loader_nrrd`.

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 2, 2021, 9:42pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/10 "2021-09-02T21:42:09Z")

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Ok, cool. In that case, here is a folder with a few nrrd files for you to try.

> **[nrrdFiles](https://www.dropbox.com/sh/ing8618lwn5r1if/AABuxUTlDJTNe7FI1Ksaaioia?dl=0)**
>
> Shared with Dropbox

One thought about the data from the knee model you mention above: Do you think that the Y and Z in that vector is noise and there should be a threshold below which it should assume 0.0, perhaps a percentage of the largest component?  
Best  
-AM

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<div class="post-metadata">

**Author:** ![Mugen87](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/mugen87/32/5645_2.png) [@Mugen87](https://discourse.threejs.org/u/Mugen87)\
**Post date:** [September 3, 2021, 9:00am UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/11 "2021-09-03T09:00:56Z")

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I don’t know that, sorry. When I add a threshold, the file can be loaded without runtime errors but the resulting planes do not look correct. I’m afraid this issue can only be solved by someone with good understanding of the NRRD standard.

In any event, would you be willing to file an issue at GitHub? In this way, it’s possible to ping devs who could possibly help.

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<div class="post-metadata">

**Author:** ![stresstensor](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@stresstensor](https://discourse.threejs.org/u/stresstensor)\
**Post date:** [September 8, 2021, 10:57pm UTC](https://discourse.threejs.org/t/error-while-rendering-volumetric-webgl2-example-with-different-dataset/29462/13 "2021-09-08T22:57:01Z")

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Sure, I can add an issue.  
Thanks  
-AM