Offscreen rendering to a FBO with Ozone

[m.su...@gmail.com]

Is it possible to get Chromium + Ozone build to render to an offscreen FBO? Is there some interface in Ozone where a FBO is provided, such that output would be rendered to it? I am specifically trying to see if this is possible when the GPU process is providing hardware acceleration.

[Alex Sakhartchouk]

Hi,

We have a path that does something very similar in links below. We are rendering into EGL images backed by buffers created via an ozone platform.

The flow of data is along the lines of:

- Create native buffer to render into via ozone

- Bind it as a render target to an FBO

- Draw Draw Draw

- Give the produced buffer back to the ozone platform to be presented (or used however)

- Repeat (we recycle the buffers)

https://code.google.com/p/chromium/codesearch#chromium/src/content/browser/compositor/gpu_surfaceless_browser_compositor_output_surface.cc&q=surfaceless&sq=package:chromium&l=1

https://code.google.com/p/chromium/codesearch#chromium/src/ui/ozone/platform/dri/ in particular look for gbm surfaceless.

Thanks,

Alex