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Cleaned up updatePosition in Mock.Race to simplify time estimation.

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#story[875]
main
cbt24 9 years ago
parent 60458f0f7a
commit 27d4040a54
1 changed files with 28 additions and 51 deletions
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79
mock/src/main/java/seng302/Model/Race.java
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@ -239,6 +239,28 @@ public class Race implements Runnable {
return new GPSCoordinate(endPoint.getY(), endPoint.getX());
}
private VMG calculateHeading(Boat boat) {
//How fast a boat can turn, in degrees per millisecond.
double turnRate = 0.03;
//How much the boat is allowed to turn, considering how long since it last turned.
double turnAngle = turnRate * boat.getTimeSinceTackChange();
//Find the bounds on what angle the boat is allowed to travel at. The bounds cap out at [0, 360).
double bound1 = Math.max(boat.getHeading() - turnAngle, 0);
double bound2 = Math.min(boat.getHeading() + turnAngle, 360);
return boat.getPolars().calculateVMG(this.windDirection, this.windSpeed, boat.calculateBearingToDestination(), bound1, bound2);
}
private boolean improvesVelocity(Boat boat, VMG newHeading) {
double angleBetweenDestAndHeading = boat.getHeading() - boat.calculateBearingToDestination();
double angleBetweenDestAndNewVMG = newHeading.getBearing() - boat.calculateBearingToDestination();
double currentVelocity = cos(Math.toRadians(angleBetweenDestAndHeading)) * boat.getVelocity();
double vmgVelocity = cos(Math.toRadians(angleBetweenDestAndNewVMG)) * newHeading.getSpeed();
return vmgVelocity > currentVelocity;
}
/**
* Calculates the distance a boat has travelled and updates its current position according to this value.
*
@ -249,85 +271,40 @@ public class Race implements Runnable {
//distanceTravelled = velocity (nm p hr) * time taken to update loop
double distanceTravelled = (boat.getVelocity() * this.scaleFactor * millisecondsElapsed) / 3600000;
double totalDistanceTravelled = distanceTravelled + boat.getDistanceTravelledInLeg();
double totalDistanceTravelled;
boolean finish = boat.getCurrentLeg().getName().equals("Finish");
if (!finish) {
double totalDistanceTravelledInTack = distanceTravelled + boat.getDistanceTravelledInTack();
double bound1 = (boat.calculateBearingToDestination() - 90) % 360;
double bound2 = (boat.calculateBearingToDestination() + 90) % 360;
//TODO the actual bearing bounds need to be the interval in which the boat won't go out of bounds.
bound1 = 0;
bound2 = 360;
boat.setTimeSinceTackChange(boat.getTimeSinceTackChange() + this.scaleFactor * millisecondsElapsed);
//How fast a boat can turn, in degrees per millisecond.
double turnRate = 0.03; //Roughly 30 per second, or 12 seconds per revolution.
//How much the boat is allowed to turn, considering how long since it last turned.
double turnAngle = turnRate * boat.getTimeSinceTackChange();
//System.out.println("boat " + boat.getAbbrev() + " turn angle is " + turnAngle + ".");//TEMP DEBUG REMOVE
//Find the bounds on what angle the boat is allowed to travel at.
bound1 = boat.getHeading() - turnAngle;
bound2 = boat.getHeading() + turnAngle;
//The bounds cap out at [0, 360).
bound1 = Math.max(bound1, 0);
bound2 = Math.min(bound2, 360);
VMG newHeading = boat.getPolars().calculateVMG(this.windDirection, this.windSpeed,
boat.calculateBearingToDestination(), bound1, bound2);
VMG newHeading = calculateHeading(boat);
if (!GPSCoordinate.isInsideBoundary(boat.getCurrentPosition(), boundary)){
double tempHeading = (newHeading.getBearing() - this.windDirection +90)%360;
newHeading.setBearing(tempHeading);
}
//Is this new VMG better than the current VMG?
double angleBetweenDestAndHeading = boat.getHeading() - boat.calculateBearingToDestination();
double angleBetweenDestAndNewVMG = newHeading.getBearing() - boat.calculateBearingToDestination();
double currentVelocity = cos(Math.toRadians(angleBetweenDestAndHeading)) * boat.getVelocity();
double vmgVelocity = cos(Math.toRadians(angleBetweenDestAndNewVMG)) * newHeading.getSpeed();
//System.out.println("boat " + boat.getAbbrev() + " current velocity is " + currentVelocity + " knots, possible VMG is " + vmgVelocity + " knots.");//TEMP DEBUG REMOVE
if (vmgVelocity > currentVelocity) {
if (improvesVelocity(boat, newHeading)) {
boat.setHeading(newHeading.getBearing());
boat.setVelocity(newHeading.getSpeed());
boat.setTimeSinceTackChange(0);
//System.out.println("boat " + boat.getAbbrev() + " has a new bearing " + boat.getHeading() + " degrees, and is " + boat.calculateDistanceToNextMarker() + " nautical miles to the next marker. Velocity to next marker is " + boat.getVelocity() + " knots.");//TEMP DEBUG REMOVE
}
//TODO one way to fix the boat's rapid turning it to only update the velocity/heading every X seconds (e.g., every 5 seconds).
//TODO may need a lower tack period
//TODO another way would be to allow boats use a better VMG if it is within turnRate * timeSinceTackChange. E.g., after 100ms a boat can select a more optimal VMG within 5deg of their current bearing. After 500ms VMG can be within 25deg of current bearing. After 2sec it can be 100deg of bearing, etc...
//calc the distance travelled in a straight line to windward
//double angleBetweenDestAndHeading = boat.getHeading() - boat.calculateBearingToDestination();
totalDistanceTravelled = cos(Math.toRadians(angleBetweenDestAndHeading))*totalDistanceTravelledInTack;
totalDistanceTravelled = cos(Math.toRadians(boat.getHeading() - boat.calculateBearingToDestination()))*totalDistanceTravelledInTack;
boat.setDistanceTravelledInLeg(totalDistanceTravelled);
//Calculate boat's new position by adding the distance travelled onto the start point of the leg
double azimuth = boat.getHeading();
if (azimuth > 180) {
azimuth = azimuth - 360;
}
boat.setCurrentPosition(calculatePosition(boat.getCurrentPosition(),
totalDistanceTravelledInTack, azimuth));
azimuth = azimuth > 180? azimuth - 360 : azimuth;
boat.setCurrentPosition(calculatePosition(boat.getCurrentPosition(), totalDistanceTravelledInTack, azimuth));
}
}

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