public static double getTimeToHit(
double bulletSpeed, Vector3f playerPos, Vector3f enemyPos, Vector3f enemyPredictedPos) {
double d = CommFun.getDistanceBetweenPositions(playerPos, enemyPos);
double v = bulletSpeed;
double u = CommFun.getDistanceBetweenPositions(enemyPos, enemyPredictedPos);
Vector3f vec1 = CommFun.getNormalizedDirectionVector(playerPos, enemyPos);
Vector3f vec2 = CommFun.getNormalizedDirectionVector(enemyPos, enemyPredictedPos);
double alpha = Math.toRadians(vec1.angle(vec2));
double delta =
4 * d * d * u * u * Math.cos(alpha) * Math.cos(alpha) + 4 * (v * v - u * u) * d * d;
double t = (2 * d * u * Math.cos(alpha) + Math.sqrt(delta)) / (2 * (v * v - u * u));
double t2 = (2 * d * u * Math.cos(alpha) - Math.sqrt(delta)) / (2 * (v * v - u * u));
// System.out.println("t="+t+" v="+v+" d="+d+" u="+u+" t2="+t2);
if (Double.isNaN(t)) {
t = 1;
}
return t;
}
public static FiringInstructions getNewPredictingFiringInstructions(
MapBotBase bot, FiringDecision fd, float bulletSpeed) {
Vector3f playerPos = bot.getBotPosition();
Vector3f enemyPos = fd.enemyInfo.getBestVisibleEnemyPart(bot);
// Calculate the time to hit
double timeToHit = getTimeToHit(bulletSpeed, playerPos, enemyPos, fd.enemyInfo.predictedPos);
if (timeToHit <= 1.5) {
timeToHit = 1f;
}
// We add to enemy position the movement that the enemy is predicted to do in timeToHit.
Vector3f hitPoint = CommFun.cloneVector(enemyPos);
// movement is between bot position, not the visible part of the bot
Vector3f movement =
CommFun.getMovementBetweenVectors(
fd.enemyInfo.getObjectPosition(), fd.enemyInfo.predictedPos);
movement = CommFun.multiplyVectorByScalar(movement, (float) timeToHit);
hitPoint.add(movement);
return new FiringInstructions(CommFun.getNormalizedDirectionVector(playerPos, hitPoint));
}