public static void Update(EntityComponentStorage ecs, GameTime gameTime)
{
Vector2 oldPos;
Vector2 newPos;
// for all entities with a position component
foreach (Eid posEid in ecs.componentEids[ecs.ComponentCids[typeof(PositionComponent)]])
{
// position component of current entity changes according to that entities movement component
PositionComponent posComp =
((PositionComponent)ecs.Entities[posEid].Components[
ecs.ComponentCids[typeof(PositionComponent)]]);
// entity movement component stores velocity
MovementComponent moveComp =
((MovementComponent)ecs.Entities[posEid].Components[
ecs.ComponentCids[typeof(MovementComponent)]]);
if (posComp != null && moveComp != null)
{
// new position += delta * speed
oldPos = posComp.Position;
newPos = oldPos +
Vector2.Multiply(moveComp.Velocity,
(float)gameTime.ElapsedGameTime.TotalMilliseconds
);
posComp.Position = newPos;
}
}
}
// for now, camera follows entity with eid <see cref="CurCameraEid"/>
public static void Update(EntityComponentStorage ecs, GameTime gameTime)
{
if (CurCameraEid != null)
{
_cameraComponent = (CameraComponent)(ecs.Entities[(int)CurCameraEid].
Components[ecs.ComponentCids[typeof(CameraComponent)]]);
_positionComponent = (PositionComponent)(ecs.Entities[(int)CurCameraEid].
Components[ecs.ComponentCids[typeof(PositionComponent)]]);
_movementComponent = (MovementComponent)(ecs.Entities[(int)CurCameraEid].
Components[ecs.ComponentCids[typeof(MovementComponent)]]);
if ((_cameraComponent != null) && (_positionComponent != null))
{
var moveFactor = _movementComponent.MoveSpeed *
(float)gameTime.ElapsedGameTime.TotalSeconds;
_cameraComponent.Position +=
new Vector3((_positionComponent.Position.X - _cameraComponent.Position.X) *
moveFactor.X,
(_positionComponent.Position.Y - _cameraComponent.Position.Y) *
moveFactor.Y,
0
);
}
else
{
System.Diagnostics.Debug.WriteLine("Sorry Sir! Null component reference");
}
}
}
public static void Draw(EntityComponentStorage ecs)
{
Component renderComponent;
Component positionComponent;
Texture2D renderSpriteSheet = null;
Rectangle renderRect = new Rectangle(0, 0, 0, 0);
Vector2 renderToPos = new Vector2(0, 0);
// render all entities with a position component
foreach (Eid renderEid in ecs.componentEids[ecs.ComponentCids[typeof(RenderComponent)]])
{
renderComponent = ecs.Entities[renderEid].Components[
ecs.ComponentCids[typeof(RenderComponent)]];
positionComponent = ecs.Entities[renderEid].Components[
ecs.ComponentCids[typeof(PositionComponent)]];
// need position & render components
if (positionComponent != null && renderComponent != null)
{
renderToPos = ((PositionComponent)positionComponent).Position;
renderSpriteSheet = ((RenderComponent)renderComponent).SpriteSheet;
renderRect = ((RenderComponent)renderComponent).Rect;
RPGGame.spriteBatch.Draw(renderSpriteSheet,
renderToPos,
renderRect,
Color.White
);
}
}
}
public MovementComponent(
EntityComponentStorage ecs, Vector2 velocity, Vector2 moveSpeed) :
base(ecs)
{
this.Velocity = velocity;
this.MoveSpeed = moveSpeed;
}
public RenderComponent(EntityComponentStorage ecs,
Texture2D spriteSheet,
Rectangle rect
) : base(ecs)
{
this.SpriteSheet = spriteSheet;
this.Rect = rect;
}
public CameraComponent(EntityComponentStorage ecs, Eid curCameraEid,
Vector3 origin, Vector3 position, float scale) : base(ecs)
{
this.Origin = origin / scale; // since transform matrix multiplied by scale
this.Position = position;
this.Scale = scale;
CameraSystem.CurCameraEid = curCameraEid;
}
public static void Update(EntityComponentStorage ecs, KeyboardState keyState)
{
// "Keys" is a monogame enum
Keys[] pressedKeys = keyState.GetPressedKeys();
// grab first entity with input component.
// input component contains no data, just indicates which Entity should be acted
// upon by InputSystem
Eid inputEid = ecs.componentEids[
ecs.ComponentCids[typeof(InputComponent)]][0];
// this entity must have a movement component
MovementComponent movementComponent =
((MovementComponent)ecs.Entities[inputEid].
Components[ecs.ComponentCids[typeof(MovementComponent)]]);
if (movementComponent != null)
{
// reset velocity of current entity
movementComponent.Velocity = Vector2.Zero;
// delegate modifies position component of the entity with input component
Action <Vector2> addToInputEntVelocity;
addToInputEntVelocity = value => ((MovementComponent)ecs.Entities[inputEid].
Components[ecs.ComponentCids[typeof(MovementComponent)]]).Velocity += value;
// appropriately modify position component of input entity
foreach (Keys pressedKey in pressedKeys)
{
switch (pressedKey)
{
case Keys.W:
addToInputEntVelocity(MovementSystem.MoveVectors.UP *
movementComponent.MoveSpeed);
break;
case Keys.A:
addToInputEntVelocity(MovementSystem.MoveVectors.LEFT *
movementComponent.MoveSpeed);
break;
case Keys.S:
addToInputEntVelocity(MovementSystem.MoveVectors.DOWN *
movementComponent.MoveSpeed);
break;
case Keys.D:
addToInputEntVelocity(MovementSystem.MoveVectors.RIGHT *
movementComponent.MoveSpeed);
break;
}
}
}
}
protected Component(EntityComponentStorage ecs)
{
// assign a component to a unique Cid, if this has not already been done
if (!ecs.ComponentCids.ContainsKey(this.GetType()))
{
ecs.ComponentCids.Add(this.GetType(),
(Cid)(EntityComponentStorage.NumComponents -
ecs.NumComponentsAdded - 1)
);
ecs.NumComponentsAdded++;
}
}
public PositionComponent(EntityComponentStorage ecs, Vector2 position) : base(ecs)
{
this.Position = position;
}
public InputComponent(EntityComponentStorage ecs) : base(ecs)
{
}
public MovementComponent(EntityComponentStorage ecs)
: this(ecs, new Vector2(0, 0), new Vector2(1, 1))
{
}
public HealthComponent(EntityComponentStorage ecs) : base(ecs)
{
}
public CollisionComponent(EntityComponentStorage ecs) : base(ecs)
{
}
