/// <summary>
/// Update projectile
/// </summary>
public bool Update(float elapsedTime, GameManager game)
{
if (game == null)
{
throw new ArgumentNullException("game");
}
// add elapsed time for this frame
this.elapsedTime += elapsedTime;
// normalize time
float normalizedTime = Math.Min(1.0f, this.elapsedTime / totalTime);
// compute current projectile position
Vector3 position = Vector3.Lerp(sourcePosition, destinationPosition,
normalizedTime);
// set postion into projectile transform matrix
transform.Translation = position;
// if projectile includes a particle system update its position
if (system != null)
{
system.SetTransform(systemTransform * transform);
}
// check if projectile hit any player
int playerHit = game.GetPlayerAtPosition(position);
// if a player is hit or reached destination explode projectile
if ((playerHit != player && playerHit != -1) ||
normalizedTime == 1.0f)
{
// compute explosion position moving hit point into hit normal direction
Vector3 explosionPosition =
position + 0.5f * animatedSpriteSize * transform.Backward;
// set transform to explosion position
transform.Translation = explosionPosition;
// if an animated sprite explosion is available, create it
if (animatedSpriteSize > 0)
{
game.AddAnimSprite(animatedSprite, explosionPosition,
animatedSpriteSize, 10.0f, animatedSpriteFrameRate,
animatedSpriteDrawMode, -1);
}
// if splash damage is available, apply splash damage to nearby players
if (explosionDamageRadius > 0)
{
game.AddDamageSplash(player, explosionDamage,
explosionPosition, explosionDamageRadius);
}
// if exploded on a player add contact damage
if (playerHit != -1 && game.GetPlayer(playerHit).IsAlive)
{
game.AddDamage(player, playerHit, contactDamage,
Vector3.Normalize(destinationPosition - sourcePosition));
}
// if explosion sound is available, play it
if (explosionSound != null)
{
game.PlaySound3D(explosionSound, explosionPosition);
}
// add explosion particle system
if (projectileType == ProjectileType.Missile)
{
game.AddParticleSystem(
ParticleSystemType.MissileExplode,
transform);
}
else
if (projectileType == ProjectileType.Blaster)
{
game.AddParticleSystem(
ParticleSystemType.BlasterExplode,
transform);
}
// kill trail particle system
if (system != null)
{
system.SetTotalTime(-1e10f);
}
// return false to kill the projectile
return(false);
}
// return true to keep projectile alive
return(true);
}
/// <summary>
/// Updates the player ship for given elapsed time
/// </summary>
public void Update(
float elapsedTime, // elapsed time on this frame
CollisionMesh collision, // level collision mesh
EntityList entities) // level spawn points
{
if (collision == null)
{
throw new ArgumentNullException("collision");
}
if (entities == null)
{
throw new ArgumentNullException("entities");
}
// updates damage screen time (zero for no damage indication)
damageTime = Math.Max(0.0f, damageTime - elapsedTime);
// if player dead
if (IsAlive == false)
{
// disable engine particle system
particleBoost.Enabled = false;
// updates dead time (if zero, player is alive)
deadTime = Math.Max(0.0f, deadTime - elapsedTime);
// if player dead time expires, respawn
if (IsAlive == true)
{
// reset player to a random spawn point
Reset(entities.GetTransformRandom(random));
// add spawn animated sprite in front of player
Vector3 Pos = movement.position + 10 * movement.rotation.Forward;
gameManager.AddAnimSprite(AnimSpriteType.Spawn,
Pos, 140, 80, 30, DrawMode.Additive, playerIndex);
// play spawn sound
gameManager.PlaySound("ship_spawn");
// reset energy, shield and boost
energy = 1.0f;
shield = 1.0f;
boost = 1.0f;
missileCount = 3;
}
return;
}
// hold position before movement
Vector3 lastPostion = movement.position;
// update movement
movement.Update(elapsedTime);
// test for collision with level
Vector3 collisionPosition;
if (collision.BoxMove(box, lastPostion, movement.position,
1.0f, 0.0f, 3, out collisionPosition))
{
// update to valid position after collision
movement.position = collisionPosition;
// compute new velocity after collision
Vector3 newVelocity =
(collisionPosition - lastPostion) * (1.0f / elapsedTime);
// if collision sound enabled
if (collisionSound)
{
// test collision angle to play collision sound
Vector3 WorldVel = movement.WorldVelocity;
float dot = Vector3.Dot(
Vector3.Normalize(WorldVel), Vector3.Normalize(newVelocity));
if (dot < 0.7071f)
{
// play collision sound
gameManager.PlaySound("ship_collide");
// set rumble intensity
dot = 1 - 0.5f * (dot + 1);
gameManager.SetVibration(playerIndex, dot * 0.5f);
// disable collision sounds until ship stops colliding
collisionSound = false;
}
}
// set new velocity after collision
movement.WorldVelocity = newVelocity;
}
else
{
// clear of collisions, re-enable collision sounds
collisionSound = true;
}
// update player transform
transform = movement.rotation;
transform.Translation = movement.position;
// compute inverse transform
transformInverse = Matrix.Invert(transform);
// get normalized player velocity
float velocityFactor = movement.VelocityFactor;
// update bobbing
bobbingTime += elapsedTime;
float bobbingFactor = 1.0f - velocityFactor;
float time = GameOptions.ShipBobbingSpeed * bobbingTime %
(2 * MathHelper.TwoPi);
float distance = bobbingFactor * GameOptions.ShipBobbingRange;
bobbing.M41 = distance * (float)Math.Sin(time * 0.5f);
bobbing.M42 = distance * (float)Math.Sin(time);
bobbingInverse.M41 = -bobbing.M41;
bobbingInverse.M42 = -bobbing.M42;
// compute transform with bobbing
Matrix bobbingTransform = bobbing * transform;
// update particle system position
particleBoost.Enabled = true;
particleBoost.SetTransform(boostTransform * bobbingTransform);
// if shield active
if (shieldUse)
{
// update shield position
animatedSpriteShield.Position = bobbingTransform.Translation +
10f * bobbingTransform.Forward;
// update shiled charge
shield -= elapsedTime / GameOptions.ShieldUse;
// if shield charge depleted
if (shield < 0)
{
// disable shield
shieldUse = false;
shield = 0;
// kill shield animated sprite
animatedSpriteShield.SetTotalTime(0);
animatedSpriteShield = null;
}
}
else
{
// change shield
shield = Math.Min(1.0f,
shield + elapsedTime / GameOptions.ShieldRecharge);
}
// if boost active
if (boostUse)
{
// increase ship maximum velocity
movement.maxVelocity = GameOptions.MovementVelocityBoost;
// apply impulse force forward
AddImpulseForce(transform.Forward * GameOptions.BoostForce);
// set particle system velocity scale
particleBoost.VelocityScale = Math.Min(1.0f,
particleBoost.VelocityScale + 4.0f * elapsedTime);
// update shield charge
boost -= elapsedTime / GameOptions.BoostUse;
// if boost depleated
if (boost < 0)
{
// disable boost
boostUse = false;
boost = 0;
}
}
else
{
// slowly returns ship maximum velocity to normal levels
if (movement.maxVelocity > GameOptions.MovementVelocity)
{
movement.maxVelocity -= GameOptions.BoostSlowdown * elapsedTime;
}
// slowly returns particle system velocity scale to normal levels
particleBoost.VelocityScale = Math.Max(0.1f,
particleBoost.VelocityScale - 2.0f * elapsedTime);
// charge boost
boost = Math.Min(1.0f,
boost + elapsedTime / GameOptions.BoostRecharge);
}
// charge blaster
blaster = Math.Min(1.0f,
blaster + elapsedTime / GameOptions.BlasterChargeTime);
// charge missile
missile = Math.Min(1.0f,
missile + elapsedTime / GameOptions.MissileChargeTime);
// update chase camera
chaseCamera.ChasePosition = transform.Translation;
chaseCamera.ChaseDirection = transform.Forward;
chaseCamera.Up = transform.Up;
chaseCamera.Update(elapsedTime, collision);
}