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  • Performance tests
    • how expensive is readback?
    • need perf tests; ad-hoc popular popular sites for now, think about evolving into perf suite
    • measure fps. somehow
    • check android, d3d9, mac, GLX
  • D3D10
    • current, hacky-ish D3D10 cross-process layers implementation just renders all content to a single "back-buffer texture". In that world, the WebGL impl on d3d10 is the best we can do on top of ANGLE in the non-sandboxed world.
    • if we update the D3D10 cross-process layers model to match the GL/Basic/D3D9 model, then it might be worthwhile to investigate sharing D3D9Ex textures across processes.
  • Priority
    • if readback incurs high overhead, GL remoting is important
    • otherwise, not very high priority
  • Implement something like "GLContextProviderRemote"
    • can use IPDL impl or chromium GL lib under that veneer
    • IPDL impl would be very easy to ramp up; perf-tuning work is unknown
    • importing chromium lib is unknown work; existing tuning is unknown
    • need to figure out unknowns before deciding
  • Security concerns (of either approach)
    • GL command stream is untrusted by GPU process (assume content process has been pwned at all times); validate in chrome
    • shaders are untrusted; validate in chrome, in addition to in content
    • use a ring buffer to copy large chunks of data content->chrome asynchronously (if use IPDL, take chromium code as is? copy it?)
    • glGetError() must be synchronous
    • chrome must maintain its own local ring-buffer metadata; must validate content commands that mutate that metadata
    • GL commands that reference data in the ring buffer (index buffers?) must copy the data out then validate it

joedrew signed up for this work.