Beispiel #1
0
    // return a list of all potential collision you may be going through
    public static CollisionInfo[] BroadPhase(Entity owner, Box2D sweep)
    {
        m_cachedList.Clear();

        // first, increase the sweep box so that it covers all the tile it is touching
        Box2D fullCover = sweep;

        fullCover.Left   = Mathf.Floor(fullCover.Left);
        fullCover.Right  = Mathf.Ceil(fullCover.Right);
        fullCover.Top    = Mathf.Ceil(fullCover.Top);
        fullCover.Bottom = Mathf.Floor(fullCover.Bottom);

        // 0.9 is not a typo, it's just using a large epsilon which is currently fine because our sweep box is currently always at least one tile large
        DebugUtils.Assert(fullCover.Width >= 0.99);
        DebugUtils.Assert(fullCover.Height >= 0.99);

        if (Input.GetKeyDown(KeyCode.F10))
        {
            DrawCollision = !DrawCollision;
        }

        // check against world
        for (float i = fullCover.Left; i + 0.9f < fullCover.Right; i += 1.0f)
        {
            for (float j = fullCover.Bottom; j + 0.9f < fullCover.Top; j += 1.0f)
            {
                if (DrawCollision)
                {
                    DebugUtils.DrawRect(new Vector2(i, j), new Vector2(i + 1.0f, j + 1.0f), Color.blue);
                }

                Vector2 checkVector = new Vector2(i + 0.5f, j + 0.5f);

                TileInfo ti   = GameManager.Instance.GetTileFromWorldPos(checkVector);
                ETile    tile = ti.Tile;
                if (WorldTile.IsCollision(tile))
                {
                    Box2D box2d = new Box2D(i, j + 1.0f, i + 1.0f, j);
                    m_cachedList.Add(new CollisionInfo(null, box2d, CollisionFlags.Wall));
                }

                // check entity as well
                // TODO: This does a double lookup from above
                List <Entity> entities = GameManager.Instance.GetEntitiesFromWorldPos(checkVector);
                if (entities == null)
                {
                    continue;
                }

                foreach (Entity entity in entities)
                {
                    // pair-wise check must be done once only to avoid obtaining multiple collisions
                    if (entity.Id <= owner.Id)
                    {
                        continue;
                    }

                    Box2D box2d = entity.Box;
                    if (entity is ItemInstance)
                    {
                        m_cachedList.Add(new CollisionInfo(entity, box2d, CollisionFlags.Item));
                    }
                    else
                    {
                        m_cachedList.Add(new CollisionInfo(entity, box2d, CollisionFlags.None));
                    }
                }
            }
        }

        // let's draw all collisions
        if (DrawCollision)
        {
            foreach (var ci in m_cachedList)
            {
                ci.Box.Draw(Color.white);
            }
        }

        return(m_cachedList.ToArray());
    }