ObscureNotes

Chair for Computer Aided Medical Procedures & Augmented Reality
Lehrstuhl für Informatikanwendungen in der Medizin & Augmented Reality

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ObscureNotes

Some conference dates and calendars. At the end are some misc notes.

Journals

Conferences & Deadlines

Calendars

Current/Upcoming Deadlines

Past Deadlines

Misc Stuff

Hardware-related Stuff

  • If you want to use oldskool parallel port devices in Wine, e.g. a chip programmer like the GALEP III, you need to do several things (of which only the first two are documented):
    • modprobe parport_pc ppdev
    • ln -s /dev/parport0 .wine/dosdevices/lpt1 (or similar)
    • add the following to .wine/user.reg (this is the really obscure part):
                [Software\\Wine\\VDM\\ppdev]
                "378"="/dev/parport0"
      
    • in winecfg, set the Windows version to Win98 and add a DLL override for msvcrt

  • If you want to run ART DTrack in Wine, you probably need the attached patch to socket.c, as DTrack does strange things with network addresses. socket.c.diff

  • If you need to add wireless communications to any kind of microcontroller-based hardware:
    • roll your own with some kind of RF transceiver (probably 433 MHz) - cheap and probably least latency, but may be lots of work
    • use off-the-shelf RF frontends
      • ELV sells 868MHz RF modules: TX868-75 (TX, 15 Euro), RX868-3V (RX, 14 Euro), RX868SH-C3 (more advanced RX, longer distances, 40 Euro)
      • you can send/receive 0/3V binary patterns (modulation/demodulation is done on the module), but you have to use some sort of microcontroller and preamble to detect your bit pattern on the air between all the noise
      • Pollin sells these: RFM-01 (RX 5€), RFM-02 (TX 5€), RFM-12 (RX/TX 8€)
    • use Bluetooth:
      • Rayson BTM-112 and BTM-330: buy at CSD Electronics or TME
        • has no antenna, but a 31 mm piece of wire is sufficient for the start (lambda/4 for 2.4 GHz)
        • really cheap, around 15 Euro
      • Parani ESD200: buy at Hantz & Partner
        • usable right out of the box, has a chip antenna and DIL-8 pins
        • unfortunately, too expensive: around 50 Euro
      • some other options: Tigal
    • use Zigbee:
      • Meshnetics ZigBit: buy at Datasphere Wireless
        • available with and without antenna
        • also quite cheap, 15 - 20 Euro
        • open source 802.15.4 stack
        • ATMega128 included!

Software-related Stuff

  • The glDrawPixels implementation of many GL drivers sucks.
    • glPixelZoom(-1,1) (common setting for camera pixel data) can trigger scaling errors - use something like -1.000001,1.000001
    • some ATI drivers read only up to 256kB of pixel data in a single call

  • The binary ATI Linux driver really sucks.
    • Internally, all buffers are ordered BGRA. Therefore, when using FBOs, a texture that is bound as a render target will get an internalformat of BGRA. However, if the first glTexImage2D call had a format of GL_RGBA, the driver will mess this up internally and happily swizzle your data around.. A workaround which doesn't hurt well-designed implementations is to pass a format parameter of GL_BGRA to the first glTexImage2D call. Subsequent calls are free to use GL_RGBA for loading data.
    • Float values can be NaN and Inf. If a shader encounters these, one would expect IEEE-compliant behaviour. However, on ATI, NaN * 0 = 0, which is nonsense. On Nvidia, NaN * 0 = NaN, as the standard says.


Edit | Attach | Refresh | Diffs | More | Revision r1.92 - 07 Apr 2015 - 10:26 - AndreasDippon

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