var varcamerapan;

while(mouse_middle == 1)
{
mouse_pos.x = pointer.x; mouse_pos.y = pointer.y;
varcamerapan -= (mouse_pos.x - (screen_size.x /2)) * time_step *0.1;
camera.tilt += (mouse_pos.y - (screen_size.y /2)) * time_step *0.1;

}
while(1)
{
varcamerapan = camera.pan
}

i dont know if it worls but it needs to be somthing like this