Simulating mouse input programmatically in OS X

Question

Is it possible to simulate the actions of a mouse from a program in OS X? Specifically, the short version is that I'm trying to simulate a touchscreen using two webcams. So assuming I can get X,Y positions, can I send information to the OS as a mouse movement or click?

Edit- Or if it's particularly easy in another operating system I'd be willing to consider that.

Answer 1

Yes, it is possible. You can use the Quartz Event Services to simulate input events.

Assuming C, I wrote this quick example:

#include <ApplicationServices/ApplicationServices.h> #include <unistd.h>  int main() {     // Move to 200x200     CGEventRef move1 = CGEventCreateMouseEvent(         NULL, kCGEventMouseMoved,         CGPointMake(200, 200),         kCGMouseButtonLeft // ignored     );     // Move to 250x250     CGEventRef move2 = CGEventCreateMouseEvent(         NULL, kCGEventMouseMoved,         CGPointMake(250, 250),         kCGMouseButtonLeft // ignored     );     // Left button down at 250x250     CGEventRef click1_down = CGEventCreateMouseEvent(         NULL, kCGEventLeftMouseDown,         CGPointMake(250, 250),         kCGMouseButtonLeft     );     // Left button up at 250x250     CGEventRef click1_up = CGEventCreateMouseEvent(         NULL, kCGEventLeftMouseUp,         CGPointMake(250, 250),         kCGMouseButtonLeft     );     // Now, execute these events with an interval to make them noticeable     CGEventPost(kCGHIDEventTap, move1);     sleep(1);     CGEventPost(kCGHIDEventTap, move2);     sleep(1);     CGEventPost(kCGHIDEventTap, click1_down);     CGEventPost(kCGHIDEventTap, click1_up);     // Release the events     CFRelease(click1_up);     CFRelease(click1_down);     CFRelease(move2);     CFRelease(move1);         return 0; } 

And assuming GCC, compile with:

gcc -o program program.c -Wall -framework ApplicationServices 

Enjoy the magic.