/// <summary>
/// This function is used to orient the mob towards an arbitrary point (step)
/// </summary>
/// <param name="step">Point the mob has to face</param>
/// <param name="thresholdAngleCos">The cosine of the threshold angle, if the cos is inferior to this value, the mob will be rotated. 0.978f typically</param>
/// <param name="turningSpeed">The angle in radiants the mob will be rotated to</param>
/// <returns></returns>
/// More efficient method and the source of this at...
/// http://forums.create.msdn.com/forums/p/2693/13503.aspx
public static Quaternion OrientTowardsVector3(Pawn mob, Vector3 step, float thresholdAngleCos, float turningSpeed)
{
Vector3 mobToTargetVector = new Vector3();
Vector3 mobOrient = new Vector3();
int rotationSign = 0;
float mobToTargetAngle;
Vector3 crossProduct = new Vector3();
//We calculate the target to mob vector.
mobToTargetVector = Vector3.Normalize(step - mob.Position);
//We calculate the direction vector in the X,Y reference plane
mobOrient = Vector3.Transform(new Vector3(0.0f, 1.0f, 0.0f), Matrix.CreateFromQuaternion(mob.Rotation));
//The cross product gives out the cosine of the angle.
mobToTargetAngle = Vector3.Dot(mobToTargetVector, mobOrient);
if (mobToTargetAngle < thresholdAngleCos /*0.978f*/) // if the cosine value is inferior to a preset value, we have to turn
{
crossProduct = Vector3.Cross(mobToTargetVector, mobOrient);
//If the cross product is positive regarding the z axis then we have to turn in the anti trigonometric sense
//If the cross product is negative regarding the z axis then we have to turn in the trigonometric sense
rotationSign = -Math.Sign(crossProduct.Z);
return Quaternion.Concatenate(mob.Rotation, Quaternion.CreateFromAxisAngle(new Vector3(0f, 0f, 1f), rotationSign * turningSpeed));
}
else
{
// It is not necessary to turn, so we do not
return mob.Rotation;
}
}
//This shoots fireballs only right now!
public void Shoot(Vector3 fromPosition, Quaternion fromRotation, Pawn shotBy, GameTime gameTime)
{
Fireball newBullet = new Fireball(GameState, fromPosition, fromRotation, shotBy);
lastFired = gameTime.TotalGameTime.TotalMilliseconds;
}
/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
//Init some misc stuff
spriteBatch = new SpriteBatch(GraphicsDevice);
spriteFont = Content.Load<SpriteFont>("Fonts/SmallText");
thumbstick = Content.Load<Texture2D>(GameConstants.TxtThumbsticks);
ground = new Terrain(GameConstants.MdlGround, gameState);
boundingSphere = new Pawn(GameConstants.MdlSphere, gameState);
Fireball.Texture = Content.Load<Texture2D>(GameConstants.TxtFireball);
frameRate.LoadContent(spriteBatch);
//quad = new Quad(Vector3.Zero, Vector3.Backward, Vector3.Up, 1, 1);
//quadTexture = Content.Load<Texture2D>("Textures/Glass");
//quadEffect = new BasicEffect(graphics.GraphicsDevice);
//quadEffect.EnableDefaultLighting();
//quadEffect.World = Matrix.Identity;
//quadEffect.View = gameCamera.ViewMatrix;
//quadEffect.Projection = gameCamera.ProjectionMatrix;
//quadEffect.TextureEnabled = true;
//quadEffect.Texture = quadTexture;
//myBoundingBox = new BoundingBox(new Vector3(0, 0, 0), new Vector3(8, 4, 15));
//Init fuel cells
gameState.FuelCells = new FuelCell[GameConstants.NumFuelCells];
for (int index = 0; index < gameState.FuelCells.Length; index++)
gameState.FuelCells[index] = new FuelCell(GameConstants.MdlFuelcell, gameState);
//Init barriers
gameState.Barriers = new Barrier[GameConstants.NumBarriers];
int randomBarrier = random.Next(3);
for (int index = 0; index < GameConstants.NumBarriers; index++)
{
BarrierType type = BarrierType.Cube;
switch (randomBarrier)
{
case 0:
type = BarrierType.Cube;
break;
case 1:
type = BarrierType.Cylinder;
break;
case 2:
type = BarrierType.Pryamid;
break;
}
gameState.Barriers[index] = Barrier.BarrierFromType(type, gameState);
randomBarrier = random.Next(3);
}
PlaceFuelCellsAndBarriers();
//Init fuel carrier
gameState.Avatar = new FuelCarrier(GameConstants.MdlAvatar, gameState);
gameState.WireFrameModel = boundingSphere;
gameState.Projectiles = new List<Projectile>();
}
public Fireball(GameState state, Vector3 position, Quaternion rotation, Pawn parent)
: base(state, position, rotation)
{
ShotBy = parent;
GameState.Projectiles.Add(this);
}