private static DynamicTransform2 ProcessState(AsteroidsControlData data, DynamicTransform2 state, VehicleDriveControls controls, float deltaTime)
{
float appliedRotationalThrust;
if (controls.Axis1 != 0f)
{
appliedRotationalThrust = -data.RotationAcceleration * controls.Axis1;
}
else
{
appliedRotationalThrust = -state.AngularVelocity / deltaTime;
}
float originalRotationalVelocity = state.AngularVelocity;
float newRotationalVelocity = originalRotationalVelocity + appliedRotationalThrust * deltaTime;
if (Math.Abs(newRotationalVelocity) > data.MaxRotationSpeed)
{
newRotationalVelocity = Math.Sign(newRotationalVelocity) * data.MaxRotationSpeed;
appliedRotationalThrust = (newRotationalVelocity - originalRotationalVelocity) / deltaTime;
}
float rotatedAmount = deltaTime * originalRotationalVelocity + 0.5f * (deltaTime * deltaTime) * appliedRotationalThrust;
Orientation2 currentOrientation = state.Orientation;
Orientation2 resultingOrientation = currentOrientation.RotatedBy(rotatedAmount);
DynamicOrientation2 resultingDynamicOrientation = new DynamicOrientation2(resultingOrientation, newRotationalVelocity);
//Use new orientation so that rotating and accelerating rsults in different outputs than just accelerating!
Vector2 thrustDirection = resultingDynamicOrientation.Orientation.Facing;
Vector2 appliedThrust = data.Acceleration * controls.Axis2 * thrustDirection;
Vector2 originalVelocity = state.Velocity;
Vector2 newVelocity = originalVelocity + deltaTime * appliedThrust;
float intendedSpeedSq = newVelocity.LengthSquared();
if (intendedSpeedSq > (data.MaxSpeed * data.MaxSpeed))
{
//NOTE: This is not the most accurate approach, but it is somewhat simpler
newVelocity.Normalize();
newVelocity = data.MaxSpeed * newVelocity;
appliedThrust = (newVelocity - originalVelocity) / deltaTime;
}
Vector2 positionDelta = deltaTime * originalVelocity + 0.5f * (deltaTime * deltaTime) * appliedThrust;
Vector2 newPosition = state.Position + positionDelta;
DynamicPosition2 resultingDynamicPosition = new DynamicPosition2(newPosition, newVelocity);
return(new DynamicTransform2(resultingDynamicPosition, resultingDynamicOrientation));
}
public DynamicTransform2(DynamicPosition2 dynamicPosition, DynamicOrientation2 dynamicOrientation)
{
DynamicPosition = dynamicPosition;
DynamicOrientation = dynamicOrientation;
}