Another technique that’s all based in 3D would be to render your texture on one quad, and render a second geometry with a line material on top over the other rectangle:
@nettoyeur, @raganmd, thanks a lot.
The second technique reminds me the jit.gl.videoplane in jitter. We were using it a lot like that “kind of texture visualizer in opengl jitter world” to display textures and draw 3D rendering results over it.
Thanks a =gain I totally got it.
I like the style rectangle TOP fed by the other TOP itself. Very smart.