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How to remove the gloss / glare / white area from iPhone app icon?

To remove the gloss / glare / white area from iPhone app icon that iPhone adds automatically – go to the Xcode and open up the App’s Info.plist. On right side you see list like button. Press that and you’ll get new row with selectable property name. From there pick the “Icon already includes gloss..” and check the checkbox.

So in short: it’s a property in the App info.plist.

MIDI signal

MIDI signal in oscilloscope. Inverted serial 31200 bits per second. Captured from USB->MIDI adapter (SWIS). First bit time is about 32us (31.2us = microsecond ). Voltage difference was 3.92V.

A great page describing MIDI: http://www.tigoe.net/pcomp/code/serial-communication/midi which describes MIDI like:

“MIDI is a serial communications protocol, operating at 31,250 bits per second. Each byte has 8 bits, plus a start bit and a stop bit. It operates at 5 volts DC. The standard MIDI connector is a 5-pin DIN connector, and usually all connectors on the device are female, and both ends of a MIDI cable are male.”

From here http://home.roadrunner.com/~jgglatt/tech/midispec.htm :

  • MIDI is an asynchronous serial interface.
  • The baud rate is 31.25 Kbaud (+/- 1%).
  • There is 1 start bit, 8 data bits, and 1 stop bit (ie, 10 bits total), for a period of 320 microseconds per serial byte.
  • The MIDI circuit is current loop, 5 mA.
  • Logic 0 is current ON.
  • To avoid grounding loops and subsequent data errors, the input is opto-isolated. It requires less than 5 mA to turn on. The Sharp PC-900 and HP 6N138 optoisolators are satisfactory devices. Rise and fall time for the optoisolator should be less than 2 microseconds.
  • The standard connector used for MIDI is a 5 pin DIN.
  • Separate jacks (and cable runs) are used for input and output, clearly marked on a given device (ie, the MIDI IN and OUT are two separate DIN female panel mount jacks).
  • 50 feet is the recommended maximum cable length.
  • Cables are shielded twisted pair, with the shield connecting pin 2 at both ends.
  • The pair is pins 4 and 5. Pins 1 and 3 are not used, and should be left unconnected.

Working MD5 for Objective-C

  1.  
  2.  
  3. #import <CommonCrypto/CommonDigest.h>
  4.  
  5.  
  6. NSString * md5( NSString *str )
  7. {
  8.  
  9. const char *cStr = [str UTF8String];
  10.  
  11. unsigned char result[CC_MD5_DIGEST_LENGTH];
  12.  
  13. CC_MD5( cStr, strlen(cStr), result );
  14.  
  15. return [NSString stringWithFormat: @"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
  16. result[0], result[1],
  17. result[2], result[3],
  18. result[4], result[5],
  19. result[6], result[7],
  20. result[8], result[9],
  21. result[10], result[11],
  22. result[12], result[13],
  23. result[14], result[15]];
  24.  
  25. }
  26.  
  27.  

Calculating distance in Objective-C

Returns distance in meters between to coordinates.

  1.  
  1. float calcDistance(float lat1, float lon1, float lat2,float lon2)
  2. {
  3.         float R = 6371; // km
  4.         float dLat = deg2rad((lat2-lat1));
  5.         float dLon = deg2rad((lon2-lon1));
  6.         float a = sin(dLat/2.0) *
  7. sin(dLat/2.0)+cos(deg2rad(lat1))*
  8. cos(deg2rad(lat2))*sin(dLon/2.0)*sin(dLon/2.0);
  9.         float c = 2.0 * atan2(sqrt(a), sqrt(1-a));
  10.         float d = R * c;
  11.  
  12.         return d*1000;
  13. }