The trick is an Objective-C wrapper class (which then creates/calls C++ objects) which is compiled as “Objective-C++”.
Create the wrapper class normally but rename the .m file to .mm – nothing else is needed.
No need to change compile settings – I tried to do that way and couldn’t get the project to build without errors.
If you need to know which finger actually were lifted from screen when doing a multiple touch tracking, you need to check the phase variable from UITouch to see if it has been actually lifted from screen. If the single touch has ended, it’s phase will be UITouchPhaseEnded
Normally when you lift one finger, the touchesEnded is called with a set of all active touches. I wish it would be a set of only touches that have ended.
Example code:
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
{
NSSet *allTouches = [event allTouches];
for (int zz=0;zz<[allTouches count];zz++) { UITouch *touch = [[allTouches allObjects] objectAtIndex:zz]; CGPoint touchPos = [touch locationInView:self]; if (touch.phase==UITouchPhaseEnded) {
float roll = (atan2(-accValues[1], accValues[2])*180.0)/M_PI; float pitch = (atan2(accValues[0], sqrt((float)accValues[1]*(float)accValues[1] + (float)accValues[2]*(float)accValues[2]))*180.0)/M_PI;
From http://arduino.cc/forum/index.php?topic=80928.0
From http://arduino.cc/forum/index.php?topic=80928.0
/*
* Theory: all IO pins on Atmega168 are covered by Pin Change Interrupts.
* The PCINT corresponding to the pin must be enabled and masked, and
* an ISR routine provided. Since PCINTs are per port, not per pin, the ISR
* must use some logic to actually implement a per-pin interrupt service.
*/
/* Pin to interrupt map:
* D0-D7 = PCINT 16-23 = PCIR2 = PD = PCIE2 = pcmsk2
* D8-D13 = PCINT 0-5 = PCIR0 = PB = PCIE0 = pcmsk0
* A0-A5 (D14-D19) = PCINT 8-13 = PCIR1 = PC = PCIE1 = pcmsk1
*/
Setup:
PCMSK2 |= (1<<PCINT23);
PCICR |= (1 << PCIE2);
PCMSK0 |= (1<<PCINT0);
PCICR |= (1 << PCIE0);
ISR(PCINT2_vect)
ISR(PCINT0_vect)
{
code here
}
Tested running 100.000 sin() calls and it took 2594 milliseconds. That means you make call sin() at 38.55kHz. If you want to make 44.1kHz sound in real-time there’s no way you can use the sin() method.
Here’s the code I used
void SpeedTest()
{
float f = 1.23;
Serial.println(millis());
for (uint32_t i=0; i<10000; i++) { f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); f=sin(f); } Serial.println(millis()); Serial.println(f); }
A problem that pops up always. When needing to calculate heading difference between two compass courses?
float calculateHeadError(float heading, float target)
{
#define PI2 PI*2.0
while (heading<0) heading += PI2;
while (target<0) target += PI2;
while (heading>PI2) heading -= PI2;
while (target>PI2) target -= PI2;
float res = heading-target;
if ((heading
{
res =(heading+PI2)-target;
}
if ((heading>PI) && (target
This really works. From here: http://www.xenocafe.com/tutorials/php/ntp_time_synchronization/index.php
#!/usr/bin/php -q
<?php
// ntp time servers to contact
// we try them one at a time if the previous failed (failover)
// if all fail then wait till tomorrow
$time_servers = array("time.nist.gov",
"nist1.datum.com",
"time-a.timefreq.bldrdoc.gov",
"utcnist.colorado.edu");
// date and clock programs (change for your system)
$date_app = "/bin/date";
$clock_app = "/sbin/clock";
// a flag and number of servers
$valid_response = false;
$ts_count = sizeof($time_servers);
// time adjustment
// I'm in California and the clock will be set to -0800 UTC [8 hours] for PST
// you will need to change this value for your region (seconds)
$time_adjustment = 0;
for ($i=0; $i<$ts_count; $i++) {
$time_server = $time_servers[$i];
$fp = fsockopen($time_server, 37, $errno, $errstr, 30);
if (!$fp) {
echo "$time_server: $errstr ($errno)\n";
echo "Trying next available server...\n\n";
} else {
$data = NULL;
while (!feof($fp)) {
$data .= fgets($fp, 128);
}
fclose($fp);
// we have a response...is it valid? (4 char string -> 32 bits)
if (strlen($data) != 4) {
echo "NTP Server {$time_server} returned an invalid response.\n";
if ($i != ($ts_count - 1)) {
echo "Trying next available server...\n\n";
} else {
echo "Time server list exhausted\n";
}
} else {
$valid_response = true;
break;
}
}
}
if ($valid_response) {
// time server response is a string - convert to numeric
$NTPtime = ord($data{0})*pow(256, 3) + ord($data{1})*pow(256, 2) + ord($data{2})*256 + ord($data{3});
// convert the seconds to the present date & time
// 2840140800 = Thu, 1 Jan 2060 00:00:00 UTC
// 631152000 = Mon, 1 Jan 1990 00:00:00 UTC
$TimeFrom1990 = $NTPtime - 2840140800;
$TimeNow = $TimeFrom1990 + 631152000;
// set the system time
$TheDate = date("m/d/Y H:i:s", $TimeNow + $time_adjustment);
$success = exec("$date_app -s \"$TheDate\"");
// set the hardware clock (optional) - you may want to comment this out
exec("$clock_app --systohc");
echo "The server's date and time was set to $success\n";
} else {
echo "The system time could not be updated. No time servers available.\n";
}
?>
With just small changes you can make Arduino IDE better for your eyes. Try this, change theme.txt that is located in /Applications/Arduino.app/Contents/Resources/Java/lib/theme, dunno about Windows.
# GUI – STATUS
status.notice.fgcolor = #000000
status.notice.bgcolor = #54919e
status.error.fgcolor = #ffffff
status.error.bgcolor = #662000
status.edit.fgcolor = #000000
status.edit.bgcolor = #cc9900
status.font = SansSerif,plain,12
# GUI – TABS
# settings for the tabs at the top
# (tab images are stored in the lib/theme folder)
header.bgcolor = #216886
header.text.selected.color = #1a1a00
header.text.unselected.color = #ffffff
header.text.font = SansSerif,plain,12
# GUI – CONSOLE
console.font = Monospaced,plain,11
console.font.macosx = Monaco,plain,10
console.color = #000000
console.output.color = #cccccc
console.error.color = #ff3000
# GUI – BUTTONS
buttons.bgcolor = #044f6f
buttons.status.font = SansSerif,plain,12
buttons.status.color = #ffffff
# GUI – LINESTATUS
linestatus.color = #ffffff
linestatus.bgcolor = #044f6f
# EDITOR – DETAILS
# foreground and background colors
editor.fgcolor = #ffffff
editor.bgcolor = #000000
# highlight for the current line
editor.linehighlight.color=#005500
# highlight for the current line
editor.linehighlight=true
# caret blinking and caret color
editor.caret.color = #FF00FF
# color to be used for background when ‘external editor’ enabled
editor.external.bgcolor = #c8d2dc
# selection color
editor.selection.color = #888888
# area that’s not in use by the text (replaced with tildes)
editor.invalid.style = #7e7e7e,bold
# little pooties at the end of lines that show where they finish
editor.eolmarkers = false
editor.eolmarkers.color = #999999
# bracket/brace highlighting
editor.brackethighlight = true
editor.brackethighlight.color = #FF0000
# TEXT – KEYWORDS
# e.g abstract, final, private
editor.keyword1.style = #00FFFF,plain
# e.g. beginShape, point, line
editor.keyword2.style = #00FFFF,plain
# e.g. byte, char, short, color
editor.keyword3.style = #FF00FF,bold
# TEXT – LITERALS
# constants: e.g. null, true, this, RGB, TWO_PI
editor.literal1.style = #5599CC,plain
# p5 built in variables: e.g. mouseX, width, pixels
editor.literal2.style = #00FFFF,plain
# e.g. + – = /
editor.operator.style = #00FFFF,plain
# ?? maybe this is for words followed by a colon
# like in case statements or goto
editor.label.style = #7e7e7e,bold
# TEXT – COMMENTS
editor.comment1.style = #7e7e7e,plain
editor.comment2.style = #7e7e7e,plain
# LINE STATUS – editor line number status bar at the bottom of the screen
linestatus.font = SansSerif,plain,10
linestatus.height = 20
This code resets Arduino – in-line – in program, whenever called. Ugly, but works.
// definition
void(* resetFunc) (void) = 0; //declare reset function @ address 0
Source: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1288779911/3#3