User:Bluddy

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Bluddy
Name Yotam Barnoy
Team Member since 2009-09-22
Working on PSP platform
PSP Optimization
Personal webpage/BLOG -
Email -

Worked On

  • PSP
    • Suspend/resume support
    • Plugin support (ELF loader)
    • Console-oriented virtual keyboard
    • D-pad directional support
    • Eliminating the evil undead flickering bug (it was a tough one)
    • Refactoring, redesign and cleanup

Working On

  • PSP Optimization
    • Rendering speedup - done
      • Made the wait for vsync not slow down the main thread, by using callbacks. Turns out the callback mechanism that's tied to the GU is unable to call waitForVblank, but the regular callback mechanism can. This reduced the wait from 15ms on average to 3ms, part of which is due to the fact that by notifying the callback I think we switch context to another thread. Not a huge deal.
    • Timidity
      • A lot of work. May improve speed over midi, but it'll be the last optimization.
    • MP3 using Media Engine
      • I made a hack that'll do it, but unfortunately nobody knows how to use it for 22kHz mp3s, which is all of our MP3s. This means I need to reverse engineer the PSP FW in order to figure out how to do this properly (the PSP FW knows how to use the ME for 22 kHz files). So this is going to be hard too.
    • Video Speedup
      • Smush can be sped up for aligned platforms, and VFPU cache can be used in PSP
      • Check other codecs for possible speedups using VFPU
    • Other speedups
      • Do tests of cached vs uncached access
      • Improve memcpy: alignment, rotation
        • Possibly use VFPU's cache for even better performance.
      • Improve SDL audio output
        • SDL blocks when outputting audio. This is the thread we do most work in, so don't block.
        • Also, SDL creates threads that ALL have VFPU bit set. That's not efficient when switching contexts.

To Do

  • PSP
    • MP3 playback with Media Engine
    • Optimize speed in general
    • Optimize video playback speed
    • Use libTimidity for music
  • Generic virtual keyboard: take my keyboard and make it available to all. Involves switching from bitmaps to vectors.
  • Generic ELF loader