Add compass to simulator #201
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Note: Because a heading of 0 degrees in the simulator is actually due West, the compass heading is returned as the physicalAngle value less 90 modulo 360. The physical angle is also subject to error, when enabled (since, on the physical robot, it would be the wheels slipping and rotating the robot that would cause a move to go awry). uniqueID has been made actually unique (at least per run-time). References #193.
uniqueID is actually managed by the Edison; the simulator should just return the value given in the command.
Due to the nature of rounding and integers, at the old value of angleSlip, it would require a degree of error above 33 percent to cause the robot to stray 1 degree off course. However, that degree of error would mean that the robot would only travel 66 percent of the distance, which is disproportionate. At the new value, it will only require a degree of error of 5 percent to cause the same amount of drift, which is more reasonable. Also, I don't know why that cast to float was there, but it's redundant.
In C++, the % operator, which is normally the modulo operator, is actually implemented as a division remainder function, which is subtly different. In mathematics, both functions would return the same thing, i.e. the remainder of the division of two numbers. However, while the remainder in modular arithmetic is always (taken as) positive, the remainder in division can be negative if either the dividend or divisor is negative. Since there is currently no scenario in which physicalAngle should naturally become negative, the solution chosen has been to add 270 degrees to physicalAngle, instead of subtracting 90 degrees (due to the rotation of the simulator).
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To compensate for angle mirroring, the compass heading is returned as the physicalAngle value less 90 modulo 360.
The physical angle is also subject to error, when enabled.
Adjusted the value of angleSlip, to balance the effect of the degree of error on the heading and on the distance travelled.
Accounted for the implementation in C++ of the modulo function as a division remainder operation.
References #193, #164.