enable texture VFlip?

[ikaruga]

I'm porting over this shadertoy shader: https://www.shadertoy.com/view/XslGRr 

As you can see in `iChannel0`, in order to work correctly, the texture must have "VFlip" enabled. However, I do not see this option in PixiJS, nor can I find what it does. 

[ikaruga]

Looks like in webgl 1.0, it's equivalent to this: https://github.com/stevensona/shader-toy/issues/126

However, I'm using webgl 2.0... don't see that function.

As per this:https://forums.raspberrypi.com/viewtopic.php?t=62077,  it's just 1.0 - p.y (where p is the loaded texture). This *seems* to do the trick... (although, still not able to repo the same effect)

[ivan.popelyshev]

pixi doesnt have VFlip, but there's a way to directly upload textures in pixi through texture resources, like here: https://pixijs.io/examples/#/textures/gradient-resource.js

you can extend ImageResource or CanvasResource class , then in `upload` swap VFlag of webgl, call parent upload, then swap it back.

[ikaruga]

On 5/30/2022 at 1:05 AM, ivan.popelyshev said:

pixi doesnt have VFlip, but there's a way to directly upload textures in pixi through texture resources, like here: https://pixijs.io/examples/#/textures/gradient-resource.js

you can extend ImageResource or CanvasResource class , then in `upload` swap VFlag of webgl, call parent upload, then swap it back.

Sorry what? Do you mind sharing a snippet, even pseudo code? Thanks!

[ivan.popelyshev]

Maybe if I have time this week, its 10-15 minutes challange.

[ikaruga]

On 6/3/2022 at 3:31 AM, ivan.popelyshev said:

Maybe if I have time this week, its 10-15 minutes challange.

Any progress?

[ivan.popelyshev]

Nope, still very busy. You can try getting help at pixijs discord