Offscreen Rendering without PBuffer

OpenGL Development JOGL Development
#1

Ho can i do Off-screen rendering without a PBuffer?

I have seen that in GLJPanel it used a offscreenDrawable created trough a GLDrawableFactoryImpl.createOffscreenDrawable();

May i use the same in my application. Is it JSR-231 compliant??

#2

Hi,
If you’re not on a headless system you can create a 1x1 pixel GLCanvas and use a Frame buffer object to draw your offscreen content.

#3

yes, framebuffer objects could be used for that, but they are not available on older graphics cards.

btw: can someone explain me the differences between a Context and a Drawable?

thanks!

#4

A drawable is the rendering target or “surface”, such as an on-screen window or an off-screen pbuffer. A drawable can have multiple contexts. A context holds rendering state, and you can switch among multiple contexts using makeCurrent() / release().