private static PhysicalVector2 GetStartingPosition(
Physical.PosRectangle playerPosRectangle,
Physical.Orientation.Cardinal orientation,
Physical.Rectangle rectangle
)
{
PhysicalVector2 result =
playerPosRectangle.GetCenteredBound(orientation);
switch (orientation)
{
case Physical.Orientation.Cardinal.Left:
result.X -= (rectangle.Width / 2);
break;
case Physical.Orientation.Cardinal.Right:
result.X += (rectangle.Width / 2);
break;
case Physical.Orientation.Cardinal.Up:
result.Y -= (rectangle.Height / 2);
break;
case Physical.Orientation.Cardinal.Down:
result.Y += (rectangle.Height / 2);
break;
}
return(result);
}
private static void HandleCollision(
Ecs.Registry registry,
Queue <Entity> toRemove,
Entity entity,
Comps.Solid solidComp,
Comps.Position positionComp,
Comps.Shapes.Rectangle rectangleComp,
PhysicalVector2 tilePosition,
Rectangle tileRectangle
)
{
if (solidComp.ephemeral)
{
toRemove.Enqueue(entity);
}
else
{
PhysicalVector2 correction = GetMinCorrection(
rectangleComp.data, positionComp.data,
tileRectangle, tilePosition
);
positionComp.data += correction;
}
}
public static void Run(
Ecs.Registry registry,
IMap map
)
{
// To avoid performance costs from doing list intersections, only
// query for entities with `Solid` components.
//
// However, we can assume that all entities with a `Solid` component
// also have these components:
// - `Position`
// - `Shape.Rectangle`
List <Entity> entities = registry.GetEntitiesList(typeof(Comps.Solid));
// Queue entities to remove so we aren't removing entities while
// iterating over them
Queue <Entity> toRemove = new Queue <Entity>();
foreach (Ecs.Entity entity in entities)
{
var entityRect = registry.GetComponentUnsafe <Comps.Shapes.Rectangle>(entity);
var entityPos = registry.GetComponentUnsafe <Comps.Position>(entity);
var entityPosRect = new PosRectangle(entityPos.data, entityRect.data);
// Check every tile that the rectangle is touching.
foreach (int index in OverlappingTiles(map, entityPosRect))
{
var gameTile = (GameTile)map.GameLayer.tiles[index];
switch (gameTile.kind)
{
case GameTile.Kind.Solid:
var tilePos = GetTilePosition(map, index);
var tileRect = new Rectangle(
map.TileWidth,
map.TileHeight
);
if (CheckCollision(
entityRect.data, entityPos.data,
tileRect, tilePos
))
{
var entitySolid = registry.GetComponentUnsafe <Comps.Solid>(entity);
HandleCollision(
registry, toRemove,
entity, entitySolid, entityPos, entityRect,
tilePos, tileRect
);
}
break;
}
}
}
ProcessRemoves(toRemove, registry);
}
public static Entity Create(
Comps.Projectile.Kind kind,
Entity owner,
Ecs.Registry registry
)
{
// Assume that `owner` has position and orientation
// components
var playerPositionComp = registry
.GetComponentUnsafe <Comps.Position>(owner);
var playerRectangleComp = registry
.GetComponentUnsafe <Comps.Shapes.Rectangle>(owner);
var playerOrientationComp = registry
.GetComponentUnsafe <Comps.Orientations.Cardinal>(owner);
var playerPosRectangle = new Physical.PosRectangle(
playerPositionComp.data,
playerRectangleComp.data
);
// Create projectile
Physical.Rectangle rectangle = new Physical.Rectangle(
16.0f * 4,
16.0f * 4
);
PhysicalVector2 position = GetStartingPosition(
playerPosRectangle,
playerOrientationComp.data,
rectangle
);
var projectileEntity = registry.CreateEntity();
registry.AssignComponent(
projectileEntity,
new Comps.Shapes.Rectangle {
data = rectangle
}
);
registry.AssignComponent(
projectileEntity,
new Comps.Position {
data = position
}
);
registry.AssignComponent(
projectileEntity,
(Comps.Orientations.Cardinal)playerOrientationComp.Clone()
);
PhysicalVector2 velocity =
playerOrientationComp.data.GetPhysicalVector2() *
GetStartingSpeed(kind);
registry.AssignComponent(
projectileEntity,
new Comps.Velocity {
data = velocity,
decay = 1.0f
}
);
registry.AssignComponent(
projectileEntity,
new Comps.Projectile {
kind = kind,
ownerId = owner.id
}
);
if (IsDamaging(kind))
{
registry.AssignComponent(
projectileEntity,
new Comps.Damaging {
damage = 1,
attackerId = owner.id
}
);
}
registry.AssignComponent(
projectileEntity,
new Comps.Lifetime {
ticks = GetLifetime(kind)
}
);
registry.AssignComponent(
projectileEntity,
new Comps.Solid {
ephemeral = true
}
);
return(projectileEntity);
}