/// <summary>
/// Performes the bullet releasing in the shoot process
/// </summary>
/// <param name="gameTime">Game time</param>
/// <param name="position">Start position</param>
/// <param name="azimuth">Flight direction</param>
/// <param name="visualiseBullet">Whether the bullet should be visualised indicator</param>
/// <returns>True if the bullet hit something</returns>
bool PerformShoot(GameTime gameTime, PositionInTown position, float azimuth, bool visualiseBullet)
{
const float bulletWidth = 0.02f;
//const float startHeight = 0.5f;
const float bulletWidthHalf = bulletWidth / 2;
bool solveHeight = (Holder is Player);
double lookAngle = Holder.LookAngle;
//Vector2 quarterPosition = position.PositionInQuarter;
float startHeight = Holder.FirstHeadPosition.Y - bulletWidth;
Vector2 quarterPosition = position.PositionInQuarter;
Vector2 left = quarterPosition.Go(bulletWidthHalf, azimuth - MathHelper.PiOver2);
Vector2 right = quarterPosition.Go(bulletWidthHalf, azimuth + MathHelper.PiOver2);
Quadrangle bullet = new Quadrangle(right, left, right.Go(type.Range, azimuth), left.Go(type.Range, azimuth));
TownQuarter quarter = position.Quarter;
List <Quadrangle> colliders = new List <Quadrangle>(quarter.SpaceGrid.GetAllCollisions(bullet));
colliders.RemoveAll(x => x == Holder);
//Half-interval search
Stack <RangeF> testedParts = new Stack <RangeF>();
Dictionary <float, float> heights = new Dictionary <float, float>();
testedParts.Push(new RangeF(0, type.Range));
if (solveHeight)
{
heights.Add(0, startHeight);
heights.Add(type.Range, startHeight + type.Range * (float)Math.Tan(lookAngle));
}
Quadrangle nearest = null;
float distance = type.Range;
while (testedParts.Count != 0)
{
RangeF bulletRangePart = testedParts.Pop();
float h1 = 0f;
float h2 = 0f;
if (solveHeight)
{
h1 = heights[bulletRangePart.Begin];
h2 = heights[bulletRangePart.End];
}
Quadrangle bulletPart = new Quadrangle(
left.Go(bulletRangePart.Begin, azimuth),
right.Go(bulletRangePart.Begin, azimuth),
left.Go(bulletRangePart.End, azimuth),
right.Go(bulletRangePart.End, azimuth));
List <Quadrangle> newColliders = new List <Quadrangle>(
colliders.Where(
x =>
(solveHeight && x is SpatialObject && (((SpatialObject)x).Size.Y >= h2 || ((SpatialObject)x).Size.Y >= h2) && (0 <= h1 || 0 <= h2) && x.IsInCollisionWith(bulletPart))
||
(!solveHeight && x.IsInCollisionWith(bulletPart))
)
);
if (newColliders.Count != 0)
{
if (newColliders.Count == 1 || bulletRangePart.Length <= bulletWidthHalf)
{
nearest = newColliders[0];
distance = bulletRangePart.End;
break;
}
colliders = newColliders;
float halfLength = bulletRangePart.Length * 0.5f;
float middle = bulletRangePart.Begin + halfLength;
testedParts.Push(new RangeF(middle, bulletRangePart.End));
testedParts.Push(new RangeF(bulletRangePart.Begin, middle));
if (solveHeight && halfLength != 0f)
{
heights.Add(middle, startHeight + middle * (float)Math.Tan(lookAngle));
}
}
}
if (visualiseBullet)
{
quarter.AddBullet(gameTime, new BulletVisualisation(quarter, quarterPosition, azimuth, distance, startHeight, startHeight + distance * (float)Math.Tan(lookAngle)));
}
if (nearest != null)
{
Debug.Write("Shot", nearest.ToString());
nearest.BecomeShoot(gameTime, type.Damage, Holder);
return(true);
}
return(false);
}
