Yoctopuce Yocto-Display, Руководство пользователя

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static void usage ( void )
{
cout << "Wrong command line arguments" << endl ;
cout << "usage: demo <serial_number>" << endl ;
cout << " demo <logical_name>" << endl ;
cout << " demo any (use any discovered device)" << endl ;
u64 now = yGetTickCount ();
while ( yGetTickCount () - now < 3000 ) {
// wait 3 sec to show the message
}
exit ( 1 );
}
int main ( int argc, const char * argv [])
{
string errmsg ;
string target ;
YDisplay * disp ;
YDisplayLayer * l0, * l1 ;
int w, h, x, y, vx, vy ;
if( argc < 2 ) {
usage ();
}
// Setup the API to use local USB devices
if ( yRegisterHub ( "usb" , errmsg ) != YAPI_SUCCESS ) {
cerr << "RegisterHub error: " << errmsg << endl ;
usage ();
return 1 ;
}
target = ( string ) argv [ 1 ];
if ( target == "any" ) {
disp = yFirstDisplay ();
if ( disp == NULL ) {
cout << "No module connected (check USB cable)" << endl ;
usage ();
return 1 ;
}
} else {
disp = yFindDisplay ( target + ".display" );
}
if (! disp -> isOnline ()) {
cout << "Module is offline (check USB cable)" << endl ;
usage ();
return 1 ;
}
disp -> resetAll ();
// retreive the display size
w = disp -> get_displayWidth ();
h = disp -> get_displayHeight ();
// reteive the first layer
l0 = disp -> get_displayLayer ( 0 );
l0 -> clear ();
// display a text in the middle of the screen
l0 -> drawText ( w / 2 , h / 2 , YDisplayLayer :: ALIGN_CENTER , "Hello world!" );
// visualize each corner
l0 -> moveTo ( 0 , 5 );
l0 -> lineTo ( 0 , 0 );
l0 -> lineTo ( 5 , 0 );
l0 -> moveTo ( 0 , h - 6 );
l0 -> lineTo ( 0 , h - 1 );
l0 -> lineTo ( 5 , h - 1 );
l0 -> moveTo ( w - 1 , h - 6 );
l0 -> lineTo ( w - 1 , h - 1 );
l0 -> lineTo ( w - 6 , h - 1 );
l0 -> moveTo ( w - 1 , 5 );
l0 -> lineTo ( w - 1 , 0 );
l0 -> lineTo ( w - 6 , 0 );
// draw a circle in the top left corner of layer 1
l1 = disp -> get_displayLayer ( 1 );
11. Using Yocto-Display with C++
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