# Add a custom uniform
**URL:** https://forum.deepar.ai/t/add-a-custom-uniform/294
**Category:** Studio
**Created:** [May 11, 2023, 9:13pm UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294 "2023-05-11T21:13:40Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@Randy\_Chapman](https://forum.deepar.ai/u/Randy_Chapman)
#### Post date: [May 11, 2023, 9:13pm UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/1 "2023-05-11T21:13:40Z")
Folks,
I’d like to add a custom uniform to my custom shader (call it radius, type float), with a slider for adjusting the value (much like the LUT slider). As well – in fact, the primary reason – is that I need to be able to adjust this as a parameter through the websdk as I do with “lutAmount”.
Is this possible? I’m perfectly content hacking text/json files to make it happen, if needed!
thanks!
–randy
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### Author:  [@jelena](https://forum.deepar.ai/u/jelena)
#### Post date: [May 12, 2023, 6:14pm UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/2 "2023-05-12T18:14:22Z")
Yes. You would need to select your Fragment shader and edit it in an external tool
and add a new uniform like:
> uniform vec4 lutAmount;
You can use this uniform as a parameter to the mix function
> vec4 outputColor = mix(inputColor, anotherColor, lutAmount.x);
To display it as a slider select your shader file (parent of Fragment and Vertex) and select Edit
In the shader builder you should be able to find your new uniform, select the slider from the dropdown and set min and max values
If you have issues you can send us the project with your custom shader and we can see how we can help
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### Author:  [@Abdelhamid\_3wais](https://forum.deepar.ai/u/Abdelhamid_3wais)
#### Post date: [May 14, 2023, 1:42pm UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/3 "2023-05-14T13:42:35Z")
@jelena
Is it possible design custom ui for the app to control specific stuff in the effect
For example a slider as user can adjust the LUT intensity
Picker options to enable/disable specific objects in the scene
To make the experience more interactive
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### Author:  [@Randy\_Chapman](https://forum.deepar.ai/u/Randy_Chapman)
#### Post date: [May 15, 2023, 3:34am UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/4 "2023-05-15T03:34:13Z")
Thank you! I got this working finally with the right magic of using a vec4 (not a float) and restarting the Studio. Not sure why it didn’t work the first time I tried it that way.
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### Author:  [@jelena](https://forum.deepar.ai/u/jelena)
#### Post date: [May 15, 2023, 10:57am UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/5 "2023-05-15T10:57:18Z")
@Randy_Chapman I’m glad to hear ther
@Abdelhamid_3wais Yes, but the is a different topic. You can find info on how to hande uniforms form the app here
> **[Changing filter parameters from code | DeepAR](https://docs.deepar.ai/guides-and-tutorials/changing-filter-parameters-from-code/)**
>
> Control your filters dynamically from the code
But you can use info from this thread to find the uniform names
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### Author:  [@Abdelhamid\_3wais](https://forum.deepar.ai/u/Abdelhamid_3wais)
#### Post date: [May 16, 2023, 5:04am UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/6 "2023-05-16T05:04:59Z")
Awesome 😊
Is that possible with deep ar flutter package for building easier for both ios and android ?!
@jelena
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### Author:  [@jelena](https://forum.deepar.ai/u/jelena)
#### Post date: [May 16, 2023, 3:51pm UTC](https://forum.deepar.ai/t/add-a-custom-uniform/294/7 "2023-05-16T15:51:00Z")
It should be, yes
Future changeParameter(Map\ arguments) {
return \_channel.invokeMethod(“changeParameter”, arguments);
}