topical media & game development
game-xna-intro-XnaShooter-Game-Projectile.cs / cs
// Project: XnaShooter, File: EnemyUnit.cs
// Namespace: XnaShooter.Game, Class: EnemyUnit
// Path: C:\code\XnaShooter\Game, Author: Abi
// Code lines: 167, Size of file: 4,73 KB
// Creation date: 27.12.2006 06:10
// Last modified: 27.12.2006 15:14
// Generated with Commenter by abi.exDream.com
#region Using directives
using System;
using System.Collections.Generic;
using System.Text;
using XnaShooter.Shaders;
using XnaShooter.Graphics;
using XnaShooter.Helpers;
using XnaShooter.GameScreens;
using XnaShooter.Game;
using Material = XnaShooter.Graphics.Material;
using Microsoft.Xna.Framework;
#endregion
namespace XnaShooter.Game
{
<summary>
Unit values, used for both the GameAsteroidManager to keep all
enemy units in the current level and in UnitManager for all active
units we are currently rendering.
</summary>
public class Projectile
{
#region Variables
<summary>
Weapon types
</summary>
public enum WeaponTypes
{
Rocket,
Plasma,
Fireball,
/*obs
Health,
MgItem,
PlasmaItem,
GattlingItem,
RocketItem,
EmpItem,
} // enum WeaponTypes
<summary>
Unit type, for enemy units this is 3-7 (Kamikaze - Mine).
Links to the unit settings list in UnitManager.
</summary>
public WeaponTypes weaponType;
<summary>
Damage this unit currently does. Copied from unit settings,
but increase as the level advances.
</summary>
public float damage;
<summary>
Helper for plasma and fireball effects, rotation is calculated
once in constructor and used for the effects.
</summary>
public float effectRotation;
<summary>
Max speed for this unit (calculated from unit settings, increased
a little for each level). Any movement is limited by this value.
Units don't have to fly as fast as this value, this is just the limit.
</summary>
public float maxSpeed;
<summary>
Current position of this unit, will be updated each frame.
Absolute position in 3d space.
</summary>
public Vector3 position;
<summary>
Move direction, not used for plasma projectiles, but fireballs will
be moving towards the player (but not change direction during flight).
Rockets on the other hand will slowly adjust to the player position.
</summary>
public Vector3 moveDirection;
<summary>
Own projectile? Then it flys up and damages enemies, else it
is an enemy projectile!
</summary>
public bool ownProjectile = false;
<summary>
Life time of this projectile, will die after 6 seconds!
</summary>
private float lifeTimeMs = 0;
#endregion
#region Constructor
<summary>
Create unit of specific type at specific location.
</summary>
<param name="setType">Set type</param>
<param name="setPosition">Set position</param>
public Projectile(WeaponTypes setType, Vector3 setPosition,
bool setOwnProjectile)
{
weaponType = setType;
position = setPosition;
ownProjectile = setOwnProjectile;
// 300 dmg for plasma, 1000 for rockets
damage = weaponType == WeaponTypes.Plasma ? 300 : 1000;
if (ownProjectile == false)
{
if (weaponType == WeaponTypes.Fireball)
{
Vector3 distVec = Player.shipPos - position;
moveDirection = Vector3.Normalize(
Player.shipPos + new Vector3(0, distVec.Length() / 3, 0) -
position);
damage = 70;// 75;
} // if
else if (weaponType == WeaponTypes.Rocket)
{
moveDirection = new Vector3(0, -1, 0);
damage = 110;// 125;
} // else if
} // if
if (weaponType == WeaponTypes.Rocket)
maxSpeed = 30;//80;
else if (weaponType == WeaponTypes.Plasma)
maxSpeed = 75;//150;
else if (weaponType == WeaponTypes.Fireball)
maxSpeed = 20;//45;
if (weaponType == WeaponTypes.Plasma ||
weaponType == WeaponTypes.Fireball)
effectRotation = RandomHelper.GetRandomFloat(
0, (float)Math.PI * 2.0f);
} // Unit(setType, setPosition, setLevel)
#endregion
#region Get rotation angle
private float GetRotationAngle(Vector3 pos1, Vector3 pos2)
{
// See http://en.wikipedia.org/wiki/Vector_(spatial)
// for help and check out the Dot Product section ^^
// Both vectors are normalized so we can save deviding through the
// lengths.
Vector3 vec1 = new Vector3(0, 1, 0);
Vector3 vec2 = pos1 - pos2;
vec2.Normalize();
return (float)Math.Acos(Vector3.Dot(vec1, vec2));
} // GetRotationAngle(pos1, pos2)
private float GetRotationAngle(Vector3 vec)
{
return (float)Math.Atan2(vec.Y, vec.X);
} // GetRotationAngle(pos1, pos2)
#endregion
#region Render
<summary>
Render projectile, returns false if we are done with it.
Has to be removed then. Else it updates just position.
</summary>
<returns>True if done, false otherwise</returns>
public bool Render(Mission mission)
{
#region Update movement
lifeTimeMs += BaseGame.ElapsedTimeThisFrameInMs;
float moveSpeed = BaseGame.MoveFactorPerSecond;
if (Player.GameOver)
moveSpeed = 0;
switch (weaponType)
{
case WeaponTypes.Fireball:
position += moveDirection * maxSpeed * moveSpeed;
break;
case WeaponTypes.Rocket:
if (ownProjectile)
position += new Vector3(0, +1, 0) * maxSpeed * moveSpeed * 1.1f;
else
{
// Fly to player
Vector3 targetMovement = Player.shipPos - position;
targetMovement.Normalize();
moveDirection = moveDirection * 0.95f + targetMovement * 0.05f;
moveDirection.Normalize();
position += moveDirection * maxSpeed * moveSpeed;
} // else
break;
case WeaponTypes.Plasma:
if (ownProjectile)
position += new Vector3(0, +1, 0) * maxSpeed * moveSpeed * 1.25f;
else
position += new Vector3(0, -1, 0) * maxSpeed * moveSpeed;
break;
// Rest are items, they just stay around
} // switch(movementPattern)
#endregion
#region Skip if out of visible range
float distance = Mission.LookAtPosition.Y - position.Y;
const float MaxUnitDistance = 35;
// Remove unit if it is out of visible range!
if (distance > MaxUnitDistance ||
distance < -MaxUnitDistance * 2 ||
position.Z < 0 ||
lifeTimeMs > 6000)
return true;
#endregion
#region Render
switch (weaponType)
{
case WeaponTypes.Rocket:
float rocketRotation = MathHelper.Pi;
if (ownProjectile == false)
rocketRotation = MathHelper.PiOver2 + GetRotationAngle(moveDirection);
mission.AddModelToRender(
mission.shipModels[(int)Mission.ShipModelTypes.Rocket],
Matrix.CreateScale(
(ownProjectile ? 1.25f : 0.75f) *
Mission.ShipModelSize[(int)Mission.ShipModelTypes.Rocket]) *
Matrix.CreateRotationZ(rocketRotation) *
Matrix.CreateTranslation(position));
// Add rocket smoke
EffectManager.AddRocketOrShipFlareAndSmoke(position, 1.5f, 6 * maxSpeed);
break;
case WeaponTypes.Plasma:
EffectManager.AddPlasmaEffect(position, effectRotation, 1.25f);
break;
case WeaponTypes.Fireball:
EffectManager.AddFireBallEffect(position, effectRotation, 1.25f);
break;
} // switch
#endregion
#region Explode if hitting unit
// Own projectile?
if (ownProjectile)
{
// Hit enemy units, check all of them
for (int num = 0; num < Mission.units.Count; num++)
{
Unit enemyUnit = Mission.units[num];
// Near enough to enemy ship?
Vector2 distVec =
new Vector2(enemyUnit.position.X, enemyUnit.position.Y) -
new Vector2(position.X, position.Y);
if (distVec.Length() < 7 &&
(enemyUnit.position.Y - Player.shipPos.Y) < 60)
{
// Explode and do damage!
EffectManager.AddFlameExplosion(position);
Player.score += (int)enemyUnit.hitpoints / 10;
enemyUnit.hitpoints -= damage;
return true;
} // if
} // for
} // if
// Else this is an enemy projectile?
else
{
// Near enough to our ship?
Vector2 distVec =
new Vector2(Player.shipPos.X, Player.shipPos.Y) -
new Vector2(position.X, position.Y);
if (distVec.Length() < 2.75f)//3)
{
// Explode and do damage!
EffectManager.AddFlameExplosion(position);
Player.health -= damage / 1000.0f;
return true;
} // if
} // else
#endregion
// Don't remove unit from units list
return false;
} // Render()
#endregion
} // class Unit
} // namespace XnaShooter.Game
(C) Æliens
20/2/2008
You may not copy or print any of this material without explicit permission of the author or the publisher.
In case of other copyright issues, contact the author.
