How to set GL_LINEAR as default on QOpenGLFramebufferObject ?

[delamor]

I'm having scaling issues while rendering from a hw surface and I've discovered that's because QOpenGLFramebufferObject has set

GL_TEXTURE_MIN_FILTER -> GL_NEAREST
GL_TEXTURE_MAG_FILTER -> GL_NEAREST

By default (https://code.woboq.org/qt5/qtbase/src/gui/opengl/qopenglframebufferobject.cpp.html#516)

How can I change this to be GL_LINEAR ? There's not public api for that but I'm pretty sure that should be a way to do this, as it's something more than one will need to change..

[delamor]

If found the way by myself, if this can help to someone, is a question of attaching the texture again and change it before the fbo generation.

Like:
```
glBindTexture(GL_TEXTURE_2D, d->fbo->texture());
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); // Linear Filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // Linear Filtering