OpenGLES • Pi4 export EGL image DMA-buf and import as libdrm framebuffer

Hi,
We have OpenGL ES rendering implemented in our application using libdrm/libgbm without X to drive a DPI 640 x 480 display. We are looking to display one of the GL textures from the EGL context on a second monitor (HDMI) simultaneously.

We are using quite a bit of the Rpi4s GPU resources already and creating a second shared EGL context on another thread drawing to the second crtc seems inefficient.

So I had an idea to try and export a DMA buf from the EGL texture and then import it into libdrm as the backing for the drm framebuffer. I'm not sure if this is something the Pi4 supports though, any chance anyone knows?

Thanks

Statistics: Posted by PeartreeStudios — Thu Apr 04, 2024 7:23 pm

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