Basic Feedback and buffer implementaion with glsl FOR android

[Jpuppper]

Hello everyone ! .

Im having a problem trying to pass a previously buffer to a fragment shader in Android.

My solution works in PC but not in android.
The shader works in android but without seeing any feedback.

Also i´ve tried to pass it a sampler 2D image as a uniform to the shader in android wich works so makes me think that im not working well with buffers.

Here youll be able to see the running sketch :
http://mmtt.com.ar/effect2/

As you can see in PC you can see the feedback and in Android no.

i´ve adapted the code from this stackoverflow:

Feedback Loop THREE.js

In wich the user claim it works for android but no for me.

Here is a link with the source code.

effect2.rar

also i´ve tryed this implemantion wich comes from this post:

Basic Feedback and Buffer Implementation with GLSL Shaders

Hey! Have just started playing round with ThreeJS and I’m trying to set up a basic example of a ThreeJS project with GLSL shaders and a Frame Buffer so that I can start experimenting with Feedback effects. The basic idea is simple enough to me, render the shader to a texture and then pass that texture back into the shader. I did a shadertoy implementation of the minimal, feedback shader I’m trying to implement in ThreeJS: https://www.shadertoy.com/view/MdlBDn And I’m trying to get it workin…

But is not working.

When I try the feedback from the three.js example :
https://threejs.org/examples/#webgl_postprocessing_afterimage
it works in android BUT i need it to pass it like a texture in my shader and not using it inside the composer :

Any comment or things to try is greatly aprecciated.

Thanks for the help

[Mugen87]

@Jpuppper

The shader works in android but without seeing any feedback.

In this case I suggest you check if there are warnings or errors logged in the browser console. You do this like so:

• Enable “USB Debugging” for your smartphone. You can do this in the “Developer Options” menu.
• Connect your smartphone with your computer via USB.
• Open (desktop) Chrome and use the following URL chrome://inspect/#touch-devices
• Wait until Chrome recognizes your smartphone. You can then inspect your app in a separate window which allows you access to the browser console and debugging features.

[Jpuppper]

Finally I make it work !!!

I take the code from other site wich also does feedback shader :

i´ve uploaded a repo with the example

jpupper/WebShaderGallery